HEP Phenomenology·hep-ph

Wed·Sep 9, 2026Wednesday·September 9, 2026

107 papers—82 primary·25 cross-listed

01
Minimal spontaneous baryogenesis from flavor
Martin A. Mojahed🇮🇹 · Alfredo Stanzione🇮🇹
In its minimal realization, the Froggatt-Nielsen (FN) mechanism addresses the Standard Model (SM) flavor puzzle via the spontaneous breaking of a horizontal $U (1)_{H}$ symmetry. If $U (1)_{H}$ is global and broken before the end of inflation, it gives rise to a pseudo-Nambu-Goldstone boson (axion-like particle) with a homogeneous initial misalignment, whose subsequent coherent evolution sources spontaneous $C P T$ violation in the SM sector. We show that in the presence of $B - L$ -violating processes $-$ parametrized here model-independently via the dimension-five Weinberg operator responsible for light neutrino masses $-$ the minimal FN setup can generate the baryon asymmetry of the Universe (BAU), linking the origin of flavor directly to the BAU and neutrino masses. Solving a complete set of evolution equations for SM asymmetries, we demonstrate that this mechanism can readily yield a baryon asymmetry comparable to the observed value, or even exceeding it by several orders of magnitude. Accounting for baryonic isocurvature and entropy dilution from axion decays, we find that the observed BAU is successfully reproduced for axion oscillation temperatures above $1 0^{11}$ GeV and axion decay constants ranging from $1 0^{13 \dots 14}$ GeV to above $1 0^{17}$ GeV. Finally, while we focus on a global $U (1)_{H}$ symmetry and axion motion from standard misalignment, our framework is readily extendable to other global horizontal symmetries and arbitrary axion motion.
hep-ph0 citations
02
The Colors of Jet Quenching
Hannah Bossi🇺🇸 · Maxence Larose🇺🇸 · Yacine Mehtar-Tani🇺🇸
We combine inclusive jet nuclear modification factors with energy-energy correlators to perform a data-driven extraction of the quark and gluon quenching factors and the medium resolution scale from the small-angle region. Taking coherent energy loss as a null hypothesis, we find jet quenching factors incompatible with Casimir scaling. Incorporating color decoherence through antenna energy loss improves the description of the data and restores Casimir scaling, providing evidence that the quark-gluon plasma partially resolves the internal structure of jets in heavy-ion collisions.
hep-phhep-exnucl-th0 citations
03
Energy-energy correlators and color decoherence from a generating functional
Yacine Mehtar-Tani🇺🇸
Using jet calculus at leading-logarithmic accuracy, we develop a generating-functional approach to describe the hard-collinear sector of jets propagating through the quark-gluon plasma. This framework yields coupled evolution equations for the jet nuclear modification factor and energy-energy correlators (EECs). We first construct the EEC evolution in the fully incoherent regime, and then derive evolution equations that account for the transition from the coherent to the incoherent limit in the large- $N_{c}$ limit. Furthermore, we show that combining the EEC with the jet nuclear modification factor provides complementary sensitivity to the overall jet suppression and to medium-induced modifications of the jet's internal structure. This framework therefore offers a way to constrain the magnitude and flavor dependence of jet energy loss, together with the medium resolution angle governing color decoherence.
hep-phnucl-th0 citations
04
High-sensitivity Ultralight Dark Matter detector: Parametrically Amplified Casimir Devices
Muping Chen🇯🇵 · Hideo Iizuka🇯🇵 · Kyohei Mukaida🇯🇵 · Kazunori Nakayama🇯🇵 · Burkhant Suerfu🇯🇵
We propose the use of sphere-and-plate Casimir force measurement setups to detect ultralight vector dark matter. We demonstrate that sub-picometer signals can be parametrically amplified to be detectable. We present a novel improvement that allows the continuous tuning of the natural frequency of the system, opening new research opportunities at the submicron scale. We show that the improved setup can determine the dark matter mass with high accuracy, significantly expand the detectable mass range, and achieve the best sensitivity to date in the $8 \times 1 0^{- 14} \sim 1 \times 1 0^{- 12} eV$ mass range.
hep-phastro-ph.CO0 citations
05
Macroscopic dark matter constraints for extended mass functions
Zachary S. C. Picker🇺🇸 · Andrew Buchanan🇨🇦 · Melissa Diamond🇨🇦 · Joseph Bramante🇨🇦
We compile and recompute a subset of the landscape of constraints for macroscopic dark matter (macros), explicitly including the dependence on the fraction of dark matter in macros $f_{dm}$ . This allows us to map these constraints to scenarios with extended mass functions for the macros, which is a generic outcome for many of the assembly processes relevant to macro formation. We compute a number of examples of constraints for extended mass functions, finding that in many cases, wider mass functions can be severely constrained by just the interactions of the tails of the distributions. Finally, we present the code and data required for computing these limits and generating these plots in a publicly accessible repository.
hep-phastro-ph.CO0 citations
06
Agnostic search for a vector-like top partner at a lepton collider via the recoil mass technique
Higinio Valle🇲🇽 · Cristina Oropeza Barrera🇲🇽 · Oscar Ochoa-Valeriano🇲🇽
A study of the single production of a vector-like top partner $T$ at a $s = 3$ TeV $e^{+} e^{-}$ collider is presented, using a decay-mode and mass-agnostic event selection built around the recoil mass observable. The analysis relies on fully simulated samples processed through a common reconstruction and event selection chain. The baseline selection is validated without beam polarization or initial-state radiation (ISR). The impact of more realistic running conditions, including ISR together with an $e^{-}$ beam polarization of $- 80%$ , is then evaluated and the discovery reach is mapped as a function of the top partner mass $m_{T}$ and coupling strength $κ_{T}$ . In the baseline scan, the estimated statistical significance rises above $3 σ$ for the lowest benchmark masses once $κ_{T}$ exceeds approximately 0.3.
hep-phhep-ex0 citations
07
Fermion mass hierarchy and flavor signals from a $D_{4}$ dihedral symmetry within a 2HDM-Tx with four-zero textures
M. A. Arroyo-Ureña🇲🇽 · E. Díaz · J. L. Díaz-Cruz🇲🇽 · H. Hernández-Arellano
We propose an extended Texturized Two-Higgs Doublet Model (2HDM-Tx) where a discrete $D_{4}$ symmetry predicts a four-zero texture in the fermion mass matrices. In contrast to the standard ansatz where the underlying Yukawa matrices are assumed to be structurally identical, we introduce a novel configuration of non-equivalent matrices that complementarily generate a specific Hermitian four-zero mass structure. This framework naturally suppresses flavor-changing neutral currents and provides a structural rationale for the fermion mass hierarchy, while in addition including a dark matter candidate. As a concrete phenomenological application, we show that the model simultaneously accommodates the persistent neutral resonance excesses at $95 GeV$ and $152 GeV$ , satisfies current \text{LHC} Higgs data, and is consistent with the stringent upper bounds from lepton flavor violation processes. These combined constraints severely restrict the parameter space of the scalar phenomenology. Finally, we study the prospects for the discovery of the lepton-flavor violating process $h \to τ μ$ at the High-Luminosity LHC.
hep-ph0 citations
08
Deconfining Phase Transition under Real Rotation: A Matrix Model Study
Qianqian Du🇨🇳 · Jing He🇨🇳 · Yun Guo🇨🇳 · Mei Huang🇨🇳 · Enke Wang🇨🇳
We construct a matrix model to study the deconfining phase transition for a pure gluon plasma that is confined in a cylinder of radius $R$ and rotating rigidly at a real-valued angular velocity $Ω$ , satisfying $R Ω < 1$ . The deconfining phase transition arises due to the competition between two terms that constitute the matrix model. The perturbative term comes from the one-loop effective potential computed in the presence of a background field, while the non-perturbative term represents a correction to the perturbative contribution which is brought about by taking into account an effective mass of the gauge fields. Our results show that real rotation induces a radial inhomogeneity of the system and the deconfining temperature $T_{c}$ drops away from the rotation axis which is consistent with the Tolman-Ehrenfest law. As for the $Ω$ -dependence of $T_{c}$ , it relies on our assumptions of the gluon effective mass. For a constant mass, $T_{c}$ is found to always decrease with increasing $Ω$ . A non-monotonic behavior of $T_{c}$ shows up when a $Ω$ -dependent mass is considered, leading to a qualitative change in the region of small angular velocity. In addition, by setting $Ω = 0$ to eliminate rotational effects, we also demonstrate that the finite-volume effect reduces the deconfining temperature relative to the infinite-volume limit. Comparisons between our results and those from various lattice simulations and phenomenological models suggest that controversy remains over how the deconfining phase transition is modified by real rotation and further work is required to reach a definite conclusion.
hep-ph0 citations
09
Decipher the nature of glueball candidate $X (2370)$
Sheng-Qi Zhang🇨🇳 · Bing-Dong Wan🇨🇳 · Cong-Feng Qiao🇨🇳
Recent evidence for an approximately flavor-singlet assignment has strengthened the case for $X (2370)$ as a pseudoscalar glueball candidate. However, flavor singletness alone does not uniquely determine its constituent structure. Using calculated three-pseudoscalar decay ratios, we find that current data favor a flavor-singlet hybrid while remaining compatible with a trigluon glueball. More importantly, we identify two resonance-resolved ratios, $a_{0} (1450) π / [K_{0}^{*} (1430) K ˉ + c.c.]$ and $ϕϕ / [b_{1} (1235) ρ]$ , whose predicted hierarchies place the compact-tetraquark, hybrid, and trigluon-glueball realizations in parametrically separated regions. These observables convert the constituent ambiguity of $X (2370)$ into a directly testable experimental question.
hep-ph0 citations
10
Mass Generation for Axion Like Particles
Luca Merlo🇪🇸
The most widely accepted solution to the Strong CP problem is the QCD axion, whose traditional parameter space is relatively constrained. However, recent studies on exotic axion models have shown that this space can be significantly extended, opening up a wide range of previously unexplored possibilities for model building. I first review the current status of axions and axion-like particles, then focus on the challenges related to the origin of their masses and explore potential connections to other unresolved issues within the Standard Model.
hep-ph0 citations
11
Improved analyses of the electroweak phase transition and its phenomenology in the Georgi-Machacek model
Cheng-Wei Chiang🇹🇼 · Kazuki Enomoto🇹🇼
The Georgi-Machacek model is a promising new physics scenario with isospin-triplet scalar fields, whose effects can qualitatively change the nature of the electroweak phase transition compared with the Standard Model. We examine the electroweak phase transition in this model by using the thermally resummed one-loop effective potential. We also incorporate effects of custodial symmetry breaking due to radiative corrections by evolving the couplings and classical fields according to the renormalization group equations. We identify viable parameter regions by Bayesian analysis using theoretical requirements and the latest experimental bounds. We then investigate the electroweak phase transition in the resulting parameter regions and discuss its phenomenological implications, such as Higgs boson decays into neutral gauge bosons, di-Higgs production at high-energy colliders, and stochastic gravitational waves associated with a first-order electroweak phase transition. We find that parameter points for the strong first-order electroweak phase transition can be verified by these observables at next-generation experiments.
hep-ph0 citations
12
Exothermic dark matter and the 248 keV nuclear recoil in LUX-ZEPLIN
Howard Baer🇺🇸 · Vernon Barger🇺🇸
The single 248-keV nuclear-recoil candidate reported by LZ is reproduced by dark matter that downscatters, with the relic in the excited state of a pseudo-Dirac pair and a splitting \delta\simeq-350\keV. Every interpretation so far advanced is endothermic and places the splitting within a few percent of the xenon kinematic ceiling, so that the predicted count changes from zero to 143 times its central value as the halo escape speed runs from 500 to 600 km/s. The downscattering branch has no threshold speed; the same variation changes its count by 0.3 %. The ratio of counts below 70 keV to those above is 0.011, so the null standard search follows from the kinematics. A weak-strength coupling overproduces the event by 8.9\times10^{5}, so the mediator is a dark-sector one, and longevity of the relic excited state requires |\delta|<2m_e. Solving the coupled Boltzmann system removes the one free normalization. Rotating to the eigenchannels of the off-diagonal potential gives \sigma_0=(\pi/k^2)\sin^2(\delta_+-\delta_-), whose phase difference is 0.03 to 1.3 rad, so the Born rate exceeds the s-wave unitarity bound where it is used. One event then requires \sigma_p\simeq2\times10^{-42} cm^2 and a kinetic mixing \epsilon\simeq1\times10^{-6} at m_{A'}=1\GeV, with beam-dump coverage below 0.6\GeV pushing the mediator above that value. The ground state upscatters endothermically through the same operator, which excludes |\delta|\lesssim300 keV and makes the published endothermic reading the small-splitting limit of one model. The decisive test is argon, whose first form-factor zero lies at 695 keV against 94.6 keV for xenon; argon yields 4 to 6 events per tonne-year near 250 keV, where the endothermic reading is forbidden at any exposure.
hep-ph0 citations
13
Inelastic dark matter and baryon flavor symmetry in light of LUX-ZEPLIN (LZ) experiment
Hyun Min Lee🇰🇷
We present a novel model for inelastic dark matter in a simple extension of the Standard Model (SM) with a local $U (1)^{'}$ baryon flavor symmetry, such as $U (1)_{B_{i} - B_{j}}$ with $i \neq = j$ . In this framework, we realize a realistic flavor structure for the mixing Yukawa couplings due to higher dimensional operators or renormalizable couplings between the SM quarks and extra vector-like quarks that are anomaly-free by themselves. We regard a Dirac singlet fermion as being dark matter and obtaining a small mass splitting for inelastic dark matter, only after the $U (1)^{'}$ symmetry is broken spontaneously. In particular, in the scenarios of heavy dark matter of $1 TeV$ mass, we show that there is a consistent parameter space for explaining both the LZ nuclear recoil event and the correct relic density for dark matter and the existing collider and indirect detection bounds are satisfied at the same time. In this case, we predict a relatively light $Z^{'}$ boson with $10 - 20 GeV$ mass and a weak gauge coupling, suggesting a dedicated search at colliders.
hep-phastro-ph.COhep-ex0 citations
14
Planck-Scale Signatures in Vacuum Neutrino Oscillations
Bipin Singh Koranga🇮🇳 · Imran Khan🇮🇳
We present a closed-form perturbative framework for two-flavour vacuum neutrino oscillations in the presence of a weak, flavour-blind Planck-scale mass correction generated by the dimension-five Weinberg operator of the Standard Model Effective Field Theory. The perturbative treatment is developed in direct structural analogy with approaches used to describe weak Earth-matter effects. We derive simple analytical expressions for the modification of the oscillation length, the oscillation phase, and the flavour-conversion probability, valid for arbitrary neutrino mixing and baseline lengths. Unlike matter-induced perturbations, the Planck-scale correction is constant along the neutrino trajectory. Consequently, its effect on the transition probability remains bounded and independent of the baseline at the amplitude level, while the associated modification of the effective mass-squared splitting produces a phase mismatch that increases linearly with propagation distance. We further present illustrative order-of-magnitude sensitivity projections for next-generation long-baseline and reactor neutrino experiments, including DUNE, Hyper-Kamiokande, and JUNO. Our results indicate that the accumulated phase drift provides a particularly promising observable for probing Planck-scale mass corrections and for distinguishing a possible quantum-gravity contribution from conventional matter-induced effects.
hep-ph0 citations
15
Nodal filtering in open-charm decays of the $ψ (4040)$ -- $ψ (4160)$ system
Bing-Dong Wan🇨🇳
Hadronic decay channels can provide direct information on the momentum-space structure of confined quark systems. We investigate this possibility in the $ψ (4040)$ -- $ψ (4160)$ system using an instantaneous Bethe--Salpeter (BS) framework combined with a relativistic $^{3} P_{0}$ decay model. The BS solutions yield nearby bare $3^{3} S_{1}$ and $2^{3} D_{1}$ states at 4051 and 4110 MeV, respectively, whose opposite displacements from the physical vector states motivate an effective two-state level-repulsion description. By comparing the matched open-charm channels $D D ˉ$ , $D D ˉ^{*} + c.c.$ , $D_{s} D ˉ_{s}$ , and $D_{s} D ˉ_{s}^{*} + c.c.$ with the same leading $P$ -wave threshold behavior, we show that channel-dependent overlap kernels act as momentum-space nodal filters. At $M = 4146$ MeV, the $P V / P P$ width ratio is 0.253 in the nonstrange sector but 1.63 in the strange sector, reversing the ordering expected from phase space alone. The momentum-resolved amplitudes reveal that different channels weight opposite sides of the same $2 D$ nodal region differently, leading to distinct cancellation patterns and a common recoil condition, $P_{f} ≃ 0.775$ GeV, for charge-resolved $D D ˉ^{*}$ amplitude zeros. These results establish open-charm decays as a probe of momentum-space wave-function structures in heavy quarkonium.
hep-ph0 citations
16
A Mean-Field Approach to the Dielectric Response of Bulk Superconductors for Light Dark Matter Direct Detection
Chengyao Gan🇨🇳 · Hui Li🇨🇳 · Wenjing Li🇨🇳 · Zheng-Liang Liang🇨🇳 · Lin Zhang🇨🇳 · Fawei Zheng🇨🇳
The dielectric function is central to describing many-body screening effects in dark matter (DM) direct detection with condensed matter targets. Current superconducting detector analyses employ the free-electron Lindhard dielectric function to model in-medium effects, an approximation whose validity in the superconducting state remains untested. We derive the electronic dielectric function for bulk superconductors within the Bardeen-Cooper-Schrieffer (BCS) framework, incorporating the full Bogoliubov quasiparticle coherence factors in the random-phase approximation. A systematic comparison with the Lindhard function for aluminum and tungsten silicide (WSi) reveals good agreement for energy depositions $ω ≳ 5Δ$ , establishing the Lindhard function as a robust approximation for superconducting DM detectors operating in this regime.
hep-ph0 citations
17
Radiative double inverse seesaw and dark matter in an alternative gauged $U (1)_{B - L}$ model
Hiroshi Okada🇨🇳 · Labh Singh🇮🇳
We propose a concrete theoretical framework for the double inverse seesaw mechanism within an alternative gauged $U (1)_{B - L}$ model, where the tiny neutrino masses emerge radiatively at the loop level in accordance with the 't Hooft naturalness criterion. By assigning non-universal $B - L$ charges of $(- 4, - 4, 5)$ to the right-handed neutrinos, we introduce vector-like fermions and two inert singlet scalars that circulate in the loop to generate the required mass terms. The spontaneous breaking of the $U (1)_{B - L}$ symmetry leaves a remnant $Z_{2}$ symmetry, which naturally stabilizes these new particles as dark matter (DM) candidates. We systematically investigate both fermionic and bosonic DM scenarios, assuming their interactions are predominantly mediated by the $B - L$ gauge boson ( $Z^{'}$ ). Our comprehensive analysis of the relic density, direct detection, and collider bounds reveals that the fermionic DM scenario is strongly favored. In contrast, the bosonic DM via the $Z^{'}$ portal is severely constrained and largely ruled out by the latest direct detection experiments such as LZ, PandaX-4T, and XENONnT.
hep-ph0 citations
18
The Inert Doublet Model of Dark Matter and the LUX-ZEPLIN High-Recoil Event
Lei Wang🇨🇳 · Yang Xiao🇨🇳
The recent LUX-ZEPLIN (LZ) search reported a nuclear-recoil event near $248 keV$ . Such a high-recoil event can be interpreted in terms of endothermic inelastic dark matter scattering, which typically requires a mass splitting of order a few hundred keV between the initial and final dark states. The inert doublet model (IDM) provides a natural realization of this scenario through the $Z$ -mediated transition $H + N \to A + N$ . In this work, we systematically examine whether this interpretation can be consistently realized in the IDM under the relevant theoretical constraints and existing experimental bounds. We perform a detailed profile-likelihood analysis of the LZ event, and find a viable high-mass IDM region with a profile best fit at $m_{H} = 1080 GeV$ and $m_{A} - m_{H} = 369 keV$ .
hep-ph0 citations
19
Multi-Messenger and Paleo-Detector Probes of the LZ Dark Matter Signal
Meiwen Yang🇨🇳 · Quan-feng Wu🇨🇳 · Yue-Lin Sming Tsai🇨🇳 · Yi-Zhong Fan🇨🇳
The LUX-ZEPLIN collaboration recently reported a $2.6 σ$ excess at a nuclear recoil energy of $248 keV$ , challenging the standard elastic WIMP paradigm. We show that a leptophobic inelastic dark matter model with a vector mediator naturally explains this anomaly while evading all low-energy direct detection constraints. The viable parameter space features $m_{χ_{1}} > 100 GeV$ and mass splitting $δ \sim 200 - 300 keV$ . Our multi-messenger analysis reveals that neither the heavy ( $10 GeV$ ) nor light ( $10 MeV$ ) mediator scenario reproduces the Fermi-LAT Galactic center excess, and neutrino fluxes remain consistent with IceCube limits. Both scenarios predict recoil tracks near 80 nm in lead-bearing paleo-detectors. At an optimistic uranium-238 concentration of $10^{-12}$ g/g, 10 mg Gyr of exposure could yield an excess above the estimated background even when astrophysical signals are negligible. The LZ anomaly, if confirmed, points toward a dark sector with inelastic transitions and leptophobic couplings, with the paleo-detector providing the smoking-gun evidence.
hep-ph0 citations
20
Inverse seesaw and inflation in a supersymmetric 331 model from $S U (6)$
Imtiaz Khan🇨🇳 · Tianjun Li🇨🇳
We propose a $N = 1$ supersymmetric $S U (6)$ theory with an intermediate $(S U (3)_{C} \times S U (3)_{L} \times U (1)_{X})$ phase, in which common fields and operators relate the neutrinos, gauge mediation, unification, and symmetry-breaking sectors. The inverse-seesaw Dirac matrix is antisymmetric and thus has rank two, leaving one massless neutrino at leading order. The leading symmetry-allowed correction lifts this zero mode through its projection onto the left and right null vectors of the Dirac matrix, resulting in a quartic suppression by the ratio of the intermediate and ultraviolet scales. The complete unified messenger multiplets preserve the relative one-loop gauge-coupling crossing, while the supersymmetry-breaking spurion entering the messenger sector also determines the scale of lepton-number violation. The coupling governing (331) breaking fixes both the inflationary normalization and the radial mass in the broken vacuum. For the conditional heavy spectrum adopted in the threshold calculations, the gauge couplings remain perturbative. The physical scalar directions transverse to the inflaton are stable within the neutral $((Φ, Φ ˉ, S))$ subspace. These results provide the analytical scale relations among the inverse seesaw, messenger sector, unified gauge evolution, and inflation, while keeping the assumptions associated with the ultraviolet Higgs and heavy-threshold sectors explicitly.
hep-ph0 citations
21
GUT-induced FCC signatures of the LUX-ZEPLIN event
Wojciech Kotlarski🇵🇱 · Kamila Kowalska🇵🇱 · Enrico Maria Sessolo🇵🇱
The recent observation of an event with large recoil energy at LUX-ZEPLIN has found a possible explanation in terms of the inelastic scattering of a pseudo-Dirac particle like the Higgsino of the MSSM. For pseudo-Dirac dark matter, the mass splitting $δ m$ is correlated with the mass of some heavier states. While rough dimensional considerations seem to indicate mass ranges of the heavy particles hopelessly out of reach even at future colliders, we point out that this is not the case in GUT-induced scenarios. Working with a specific model based on SU(6), we show that the experimentally favored $δ m$ implies the presence of a $Z^{'}$ gauge boson with a mass in the 10s of TeV. We derive the predicted $Z^{'}$ signal in the dilepton channel and we confront it with the sensitivity of the FCC- $hh$ to $Z^{'}$ resonances. We show that the $Z^{'}$ falls squarely in reach of the early discovery potential of the FCC- $hh$ .
hep-ph0 citations
22
LZ Nuclear-Recoil Excess from Boosted Light Magnetic Dipole-dipole Dark Matter
Jin-Han Liang🇨🇳 · Zuowei Liu🇨🇳 · Van Que Tran🇹🇼 · Yongheng Xu🇳🇴
The LZ collaboration has reported a nuclear-recoil excess near 248 keV with a global significance of $2.6 σ$ . Although halo dark matter with a magnetic dipole-dipole interaction and a TeV-scale mass provides the best fit to the excess among the interactions considered by LZ, it predicts a considerable number of events at lower recoil energies, where no excess is observed. We show that a boosted velocity distribution can alleviate this tension and provide a better fit to the LZ recoil spectrum. Moreover, the boost opens up the possibility of explaining the excess with much lighter dark matter, with masses down to the GeV scale. We demonstrate these features first in a model-independent analysis and then realize them in a concrete dark matter model, in which halo dark matter annihilates into on-shell mediators that subsequently decay into boosted dark-sector particles. Our results demonstrate that boosted dark sector particles provide a viable interpretation of the LZ excess.
hep-ph0 citations
23
Solar Capture Tests of Inelastic Dark Matter after the LZ High-Recoil Event
Mattia Di Mauro🇮🇹 · Halim Shaikh🇩🇪
The LUX-ZEPLIN (LZ) Collaboration has reported a $248$ keV nuclear-recoil candidate for which endothermic dark matter (DM) gives some of the largest local significances. We study Solar-capture constraints on three simple interpretations: a thermal Higgsino, a thermal pseudo-Dirac fermion with off-diagonal vector interactions, and neutron-philic endothermic spin-dependent scattering through $O_{4}$ . The canonical full-density thermal Higgsino is excluded: its LZ-preferred splitting near $0.38, MeV$ lies below the IceCube requirement, $δ ≳ 0.51$ -- $0.56, MeV$ . For the pseudo-Dirac benchmark we find $C_{⊙} = 1.48 \times 1 0^{20}, s^{- 1}$ , but two-state kinetics strongly suppresses annihilation. Including thermally assisted $χ_{1} \to χ_{2}$ re-excitation gives a maximum $Γ_{A} ≃ 4.1 \times 1 0^{14}, s^{- 1}$ , about $1.8 \times 1 0^{5}$ below the adopted IceCube $b b ˉ$ limit. For neutron-philic $O_{4}$ scattering at $m_{χ} = 1$ TeV and $δ = 300$ keV, finite-temperature capture gives $C_{⊙} = 3.98 \times 1 0^{17}, s^{- 1}$ , with spin-response range $(1.77$ -- $9.72) \times 1 0^{17}, s^{- 1}$ . Even in equilibrium, the upper edge remains about a factor $154$ below the adopted $b b ˉ$ limit, while an aggressive no-finite- $q$ suppression plus upper-spin stress test still leaves a factor about $19$ . The $b b ˉ$ mapping is used as a representative hadronic template for the two non-Higgsino benchmarks. Solar capture therefore excludes the thermal-Higgsino interpretation but does not generically exclude endothermic explanations of the LZ candidate.
hep-phastro-ph.HEhep-th0 citations
24
Inelastic Self-interacting Dark Matter and LUX-ZEPLIN 248 keV Event in a Dirac Modular Inverse Seesaw
Pritam Das🇮🇳 · Biswajit Karmakar🇵🇱 · Satyabrata Mahapatra🇮🇳 · Partha Kumar Paul🇮🇳
We propose a novel framework that simultaneously addresses the origin of Dirac neutrino masses and the nature of self-interacting dark matter (SIDM). The model is based on an $A_{4}$ modular symmetry to ensure the Diracness of neutrinos as well as the stability of the DM. The neutrino sector realizes a Dirac Inverse Seesaw mechanism where the smallness of the neutrino mass is governed by the vacuum expectation value (VEV) of a singlet scalar $ϕ$ . This same scalar couples to a vector-like fermion DM candidate, inducing a tiny Majorana mass splitting that renders the DM pseudo-Dirac and inelastic. Crucially, the scalar also acts as a light mediator for DM self-interactions, potentially solving the small-scale structure problems of Cold DM. In light of the recent 248 keV nuclear-recoil event, LZ230616, observed by LUX-ZEPLIN (LZ) DM direct detection experiment, we demonstrate that our inelastic SIDM parameter space naturally accommodates this signal via endothermic scattering kinematics. Furthermore, the spontaneous breaking of the dark parity required for this inelasticity produces a network of cosmological domain walls. We show that the explicit symmetry breaking needed to safely annihilate these walls generates a stochastic gravitational wave background. The non-holomorphic modular symmetry reduces the free parameters, correlating neutrino observables, addressing DM phenomenology, $Δ N_{eff}$ , and gravitational-wave signatures.
hep-phastro-ph.COhep-exhep-th0 citations
25
Reggeization of quarks from next-to-eikonal high-energy QCD
Tolga Altinoluk🇵🇱 · Guillaume Beuf🇵🇱 · Jules Favrel🇵🇱 · Michael Fucilla🇵🇱
We develop a comprehensive Wilson-line formulation of quark Reggeization in QCD. Starting from a next-to-eikonal operator built from a semi-infinite Wilson line and a background-quark insertion, we identify an interpolating operator for the Reggeized quark and derive its nonlinear rapidity evolution using the background-field method. In the dilute regime, its positive-signature component exhibits Regge-pole evolution governed by the quark Regge trajectory, whereas the negative-signature sector displays mixing between quark and gluon degrees of freedom, in accordance with its known Regge-cut structure. In the planar limit, this mixing is suppressed, and Reggeization emerges without an explicit signature projection, recovering signature degeneracy. We illustrate the universality of the construction by extracting the same Reggeized-quark operator from a more general Wilson-line operator describing a gluon-to-quark transition. Furthermore, we extend the formalism to massive quarks, deriving a coordinate-space evolution kernel whose Fourier transform reproduces the massive-quark Regge trajectory. Finally, from the leading operator-mixing structure of the evolution equation and signature arguments, we show that the Reggeized-quark interpolating operator is expected to remain an eigenstate of the rapidity evolution up to next-to-leading logarithmic accuracy.
hep-phhep-th0 citations
26
Quark mass functions in Minkowski space
Elmar P. Biernat🇵🇹 · Franz Gross🇺🇸 · M. T. Peña🇵🇹 · Alfred Stadler🇵🇹
Using the Covariant Spectator Theory (CST), we calculate the dressed quark mass function and wave-function renormalization for the five quark flavors from up/down to bottom in both the spacelike and timelike regions of Minkowski space. The calculation employs a model dressed-gluon propagator fitted to lattice data in the spacelike region. The remaining free parameters of the quark self-energy are determined by fits to lattice results for the quark mass function including a constraint built into the wave-function renormalization. We perform these fits using lattice data from two different groups and find that the resulting mass predictions are within the range of the typical constituent masses used in quark models.
hep-phnucl-th0 citations
27
Geometric Phases in Two-Level Mixing: From Neutral Mesons to Holonomic Qubits and Topological Majorana Modes
Swarup Sangiri🇮🇳 · Utpal Sarkar🇮🇳 · A Taraphder🇮🇳
We investigate the geometric structure of a Hermitian two-level mixing Hamiltonian motivated by neutral meson oscillations and its connections with qubit, fermionic, and topological descriptions. Mapping the Hamiltonian to an effective qubit representation, we analyze the geometric phase associated with cyclic parameter evolution on the Bloch sphere. Without identifying the complex mixing phase with a physical CP-violation observable, we interpret it as a CP-like geometric parameter controlling the azimuthal orientation of the Hamiltonian vector and its reversal under phase conjugation. Third-order Bargmann invariants constructed from the eigenstates yield an associated discrete phase whose dependence on the mixing parameters is examined alongside the continuous geometric construction. The cyclic evolution is also represented as a single-qubit $R_{z}$ phase operation and expressed through Majorana bilinears. Extending the construction to the momentum-dependent Bogoliubov-de Gennes Hamiltonian of the Kitaev chain, we relate momentum-space winding to the topological regimes and the quantized Berry (Zak) phase in the real-parameter model, while the corresponding Bargmann construction approaches the global phase in the continuum limit. Together, these results provide a geometric perspective connecting phase structure, qubit operations, fermionic representations, and momentum-space topology within related two-level Hamiltonians.
hep-phcond-mat.otherquant-ph0 citations
28
High-Energy Nuclear Recoils from Boosted Dark Matter for the LZ 248-keV Event: Beyond the Halo-Dependent High-Velocity Tail
Haider Alhazmi🇸🇦 · Doojin Kim🇺🇸 · Kyoungchul Kong🇺🇸 · Jong-Chul Park🇰🇷 · Seodong Shin🇰🇷
The LUX-ZEPLIN (LZ) Collaboration has reported a nuclear-recoil candidate at $E_{R} = 248 \pm 2 3_{stat} \pm 2 3_{sys}$ keV, with a maximum local significance of $3.4 σ$ and a global significance of $2.6 σ$ . A prominent interpretation invokes heavy halo dark matter near an inelastic threshold and therefore depends sensitively on the poorly constrained high-speed tail of the Galactic velocity distribution. In this Letter, we propose a qualitatively different possibility based on light boosted dark matter (BDM), whose incident energy is determined primarily by the dark-sector mass spectrum. We consider multi-component scenarios in which the boosted state scatters elastically or inelastically off xenon nuclei. For elastic scattering, pseudoscalar-mediated momentum dependence suppresses low-energy recoils. Near-threshold endothermic scattering of a nearly monochromatic BDM flux can instead confine the signal between kinematically determined recoil endpoints, suppressing events in both the low- and high-energy sidebands. The upscattered state may furthermore decay invisibly within the dark sector, preserving a single-nuclear-recoil signature without requiring it to be detector-stable. We present representative benchmark spectra and discuss complementary tests using other target nuclei and large-volume liquid-scintillator experiments.
hep-phhep-ex0 citations
29
Inelastic $B - L$ scalar dark matter and the LUX-ZEPLIN event
Nobuchika Okada🇺🇸 · Osamu Seto🇯🇵
We show that our previously proposed inelastic scalar dark matter (DM) model in gauged $U (1)_{B - L}$ symmetry naturally accounts for the $2.6 σ$ high-energy recoil event recently reported by the LUX-ZEPLIN (LZ) collaboration. To satisfy the thermal relic abundance, TeV-scale scalar DM $S$ with $m_{S} ≃ m_{Z^{'}} /2$ for resonant annihilation and the gauge coupling constant $g_{B - L} \sim 0.5$ are required, where $m_{Z^{'}}$ is the mass of $U (1)_{B - L}$ gauge boson $Z^{'}$ . The resulting predicted DM-nucleon inelastic cross section of $σ_{SI} \sim 1 0^{- 45}$ cm $^{2}$ is in excellent agreement with the LZ event. This scenario can be decisively tested for future collider searches for $Z^{'}$ boson resonance.
hep-phhep-ex0 citations
30
Electromagnetic structure of strange vector mesons in nuclear medium
Parada T. P. Hutauruk🇯🇵 · Terry Mart🇮🇩 · Kazuo Tsushima🇧🇷
We investigate the in-medium modifications of the charge (electric) $G_{C}^{*} (Q^{2})$ , magnetic $G_{M}^{*} (Q^{2})$ , and quadrupole $G_{Q}^{*} (Q^{2})$ form factors of the positively charged vector meson $K^{*+}$ in symmetric nuclear matter at zero temperature within the Schwinger proper-time Nambu-Jona-Lasinio (NJL) model. In this framework, both the nuclear medium effects and the electromagnetic structure of the $K^{*+}$ meson are described consistently in the NJL model at the quark level. We find that the charge, magnetic, and quadrupole form factors are suppressed with increasing nuclear density, indicating substantial in-medium modifications of the strange vector meson's internal structure. We further obtain a charge radius of $r_{K^{*+}}^{*} = 0.74 fm$ at normal nuclear density, which is slightly smaller than the corresponding value for the $ρ^{+}$ meson, $r_{ρ^{+}}^{*} ≃ 0.75 fm$ .
hep-phnucl-th0 citations
31
Exploring the $P$ -wave bottom-strange molecular pentaquarks with the complex scaling method
Yuhang Zheng🇨🇳 · Qing-Fu Song🇨🇳 · Xiaonu Xiong🇨🇳
In this work, we perform a systematic investigation of the $P$ -wave $Σ_{b} K / Λ_{b} K^{*} / Σ_{b} K^{*}$ and $Σ_{b} K ˉ / Λ_{b} K ˉ^{*} / Σ_{b} K ˉ^{*}$ systems for all possible $I (J^{P})$ combinations. In contrast to our earlier study of the negative-parity sector [Eur. Phys. J. C \textbf{85}, 1026 (2025)], the positive-parity sector is dominated by resonances. For the coupled-channel $I (J^{P}) = 1/2 (1/ 2^{+})$ $Σ_{b} K / Λ_{b} K^{*} / Σ_{b} K^{*}$ system, we predict a narrow resonance above the $Σ_{b} K$ threshold. In the $I (J^{P}) = 1/2 (3/ 2^{+})$ $Λ_{b} K^{*} / Σ_{b} K^{*}$ system, a molecular resonance candidate is found above the $Λ_{b} K^{*}$ threshold. For the higher-isospin $I = 3/2$ sector, resonances are identified in the $Σ_{b} K^{*}$ subsystem for both $J^{P} = 1/ 2^{+}$ and $3/ 2^{+}$ cases, though both states exhibit relatively compact sizes. We also extend our analysis to the $Σ_{b} K ˉ / Λ_{b} K ˉ^{*} / Σ_{b} K ˉ^{*}$ systems, where a cutoff-sensitive resonance is found in the $I (J^{P}) = 1/2 (1/ 2^{+})$ configuration. A broad molecular resonance candidate is found below the $Σ_{b} K ˉ^{*}$ threshold in the $I (J^{P}) = 1/2 (3/ 2^{+})$ system. We hope that these predictions provide useful guidance for future experimental searches for bottom-strange molecular pentaquarks by LHCb.
hep-ph0 citations
32
Majoron-driven spontaneous leptogenesis in type-II seesaw model
Eung Jin Chun🇰🇷 · Tae Hyun Jung🇰🇷 · Jin Sun🇬🇧
We investigate a minimal realization of spontaneous leptogenesis in the type-II seesaw model, where the lepton and Higgs asymmetries are generated as decay and inverse-decay processes drive the plasma toward the displaced equilibrium dictated by a rotating Majoron background. We derive the complete set of Boltzmann equations governing the evolution of asymmetric particle densities and analytically and numerically identify the freeze-out and freeze-in regimes. The resulting asymmetries depend primarily on the triplet branching fractions and are nearly independent of the triplet mass. The asymmetry scales as the square root of the smaller branching fraction when either decay mode into leptons or Higgs fields is suppressed, reflecting the symmetry structure; the lepton number is conserved once either coupling is turned off. We also show that the Majoron background does not induce CP-asymmetric decay of the scalar triplet in the massless final state limit, and thus its impact is negligible. Our results establish spontaneous leptogenesis as a simple and robust alternative to thermal type-II leptogenesis that requires neither additional scalar triplets nor explicit CP-violating interactions.
hep-ph0 citations
33
A Dark-Dimension Origin of Geometric Inelastic Dark Matter: The LUX-ZEPLIN High-Recoil Event and Multi-Target Tests
Waqas Ahmed🇨🇳 · George K. Leontaris🇬🇷
The extended nuclear-recoil analysis of LUX-ZEPLIN (LZ) has reported one event compatible with a recoil energy near $248$ keV, motivating endothermic dark-matter scenarios with support at large recoil energy. We study a pseudo-Dirac electroweak-doublet dark-matter model embedded in a five-dimensional Dark-Dimension framework. The Standard Model and the vectorlike electroweak doublets are localized on the visible brane, while dark-number violation is communicated through a neutral bulk state. The resulting mass splitting is exponentially suppressed, $δ = δ_{UV} e^{- 2 π M R}$ , providing a geometric origin for the few-hundred-keV scale relevant to inelastic scattering. The neutral weak current is dominantly off diagonal, fixing the neutron-scale normalization at $σ_{χ n}^{Z} ≃ 1.86 \times 1 0^{- 39} c m^{2}$ . Using a two-bin Poisson diagnostic of the extended LZ recoil window, we find a shallow minimum near $(m_{χ}, δ) ≃ (1.35 \TeV, 366 \keV)$ , while the thermally motivated point $(1.1 \TeV, 360 \keV)$ lies only $Δ χ^{2} ≃ 0.21$ higher. The same benchmark is kinematically inaccessible to light targets but remains open for xenon and tungsten, providing a characteristic multi-target test of the model. For CaWO $_{4}$ we obtain an integrated tungsten rate of $3.15 \times 1 0^{- 2}$ events kg $^{- 1}$ yr $^{- 1}$ in the $95$ -- $150$ keV interval. These results connect the geometric origin of the pseudo-Dirac splitting with high-recoil direct-detection phenomenology.
hep-phhep-th0 citations
34
Probing Neutral Triple Gauge Couplings at e- p colliders
Xue-Jia Cheng🇨🇳 · Chong-Xing Yue🇨🇳 · Ji-Chong Yang🇨🇳 · Si-Tong Liu🇨🇳
The Standard Model Effective Field Theory~(SMEFT) has attracted much attention as a model-independent way for probing new physical signals. In the SMEFT framework, $e^{-} p$ colliders can be used to study new interactions of gauge bosons, such as neutral Triple Gauge Couplings~(nTGCs). We study the signals and backgrounds of six different processes at the Future Circular Collider-hadron electron~(FCC-he) and propose different event selection strategies. The expected constraints on the coefficients of the dimension-8 operators for each process, as well as the combined constraints are obtained. The results show that the sensitivity of $e^{-} p$ colliders to nTGCs is similar to the current Large Hadron Collider~(LHC) experiments and is more competitive than that of Circular Electron Positron Collider~(CEPC) experiments.
hep-phEPJC(2026)·0 citations
35
Hadronic heavy neutral lepton decays to the limit
Jonathan L. Schubert🇩🇪 · Babette Döbrich🇩🇪
Heavy Neutral Leptons are a class of hypothetical particle, motivated by simultaneously solving multiple of the standing issues of the Standard Model. In this work we investigate the decay structure of this type of particle in the hadronic picture for multi-body final states. We propose to link the resulting hadronic description to a partonic description in a seamless transition based on the hadron system's invariant mass. Beyond the impact on the total HNL lifetime, we will show that the multi-hadron channels emerging in this description can constitute interesting experimental signatures.
hep-ph0 citations
36
Chiral Doubling, Renormalization Group Fixed Points, and Dense Matter Equations of State
Chihiro Sasaki🇵🇱
We review a top-down fixed-point-extrapolation paradigm as a unified effective field theory framework for hadronic spectroscopy, dense baryonic matter, and compact star physics. By formulating our effective Lagrangian directly at renormalization group (RG) fixed points and introducing minimal symmetry breaking, we extrapolate the theory back to physical environments. In the vacuum, this framework naturally reproduces the heavy-light meson parity-doubling spectrum via light vector meson loops. In dense matter, the interplay between the chiral-invariant nucleon mass m0 and walking vector couplings reconciles gravitational-wave constraints with $2 M_{⊙}$ massive neutron stars. Generalization to a quark-hadron hybrid approach further illuminates sequential deconfinement, core stability, and baryon number fluctuations, demonstrating how underlying RG fixed points dictate hadronic dynamics from vacuum to neutron star interiors.
hep-phnucl-th0 citations
37
Pseudo-Dirac Inelastic Dark Matter in the Leptophobic $U (1)_{B}$ Model: Confronting the LUX-ZEPLIN High-Recoil Event with Collider Searches
Xin-Yu Du🇨🇳 · Wenjie Huang🇨🇳 · Keping Xie🇺🇸
Interpreting the $248$ ~keV nuclear-recoil candidate reported by LUX-ZEPLIN (LZ) as an endothermic transition needs two ingredients usually put in by hand: a stable dark state, and a coherent current that is purely off diagonal. Gauging baryon number supplies both. For the minimal dark charges $B (χ_{L}) = - 3/2$ and $B (χ_{R}) = - 9/2$ , the scalars that generate the dark masses leave an exact residual parity $P = (- 1)^{6 B}$ stabilizing the lightest state, while the same Majorana masses make the vector current transition dominated as an identity rather than a choice. At $m_{χ} = 1$ ~TeV and $δ = 300$ ~keV the model is over-determined: the observed LZ interval, a leading-order relic estimate and the LHC dijet limit meet at the single perturbatively acceptable point $(M_{Z_{B}}, g_{B}) ≃ (1.44 TeV, 0.233)$ . That point is allowed by currently existing searches but sits just below the trigger-level dijet boundary, so it is alive and not yet decided--and a re-run of that analysis on the Run-3 data at $s = 13.6$ ~TeV, already on tape, will exclude it or find it. Nor is the interpretation confined to that splitting: at $δ = 200$ ~keV, the same construction predicts a heavier mediator at comparable coupling, $M_{Z_{B}} ≃ 2.4$ - $3.0$ ~TeV with $g_{B} ≃ 0.15$ - $0.34$ , a range the HL-LHC dijet program will probe.
hep-ph0 citations
38
Vector-meson properties in a data-driven AdS/QCD model
Xun Chen🇨🇳 · Floriana Giannuzzi🇮🇹 · Stefano Nicotri🇮🇹
We investigate the properties of $ρ$ , $ψ$ , and $Υ$ mesons within a holographic AdS/QCD framework, capturing both their vacuum phenomenology and in-medium dynamics. By reconstructing flavor-specific gauge kinetic functions within a model originally developed to study thermodynamic functions, we compute the vector-meson mass spectrum, the decay constants and the hadronic vacuum polarization contributions to the anomalous magnetic moment of the muon at zero temperature. Furthermore, we evaluate the thermal spectral functions to analyze mass shifts, resonance broadening, and the melting of vector bound states in a hot and dense medium. Finally, using the Kubo formula, we extract the electrical conductivity of the plasma as a function of temperature and chemical potential.
hep-ph0 citations
39
Connecting Regge factorization and Collins-Soper evolution
Andrea Simonelli🇮🇹
The relationship between Regge factorization of amplitudes and the Collins-Soper-Sterman factorization of hadronic cross sections is explored. Seeking a unified description of rapidity divergences in high-energy scattering and transverse-momentum-dependent factorization, a connection emerges between the Collins-Soper kernel and the Regge trajectory. This provides a framework for bridging high-energy and low-transverse-momentum resummation and for future extensions of $k_{T}$ -factorization beyond leading-logarithmic accuracy.
hep-phhep-th0 citations
40
LZ nuclear recoil event from inelastic singlet-doublet scalar dark matter
Disha Bandyopadhyay🇮🇳 · Debasish Borah🇮🇳 · Pankaj Borah🇮🇳
We study the possibility of explaining the recently reported high-energy nuclear recoil event by the LUX-ZEPLIN (LZ) collaboration within the framework of singlet-doublet scalar dark matter (DM). Considering DM to be the CP even mass eigenstate formed out of a scalar doublet and a real scalar singlet, both being odd under an unbroken $Z_{2}$ symmetry, we find the parameter space of the model consistent with correct relic abundance and direct-detection limits on elastic scattering rates. A large part of the parameter space can also lead to inelastic up-scattering of DM with a rate and recoil energy consistent with the recent LZ event. Depending upon the singlet-doublet mixing, the model allows a much wider range of currently allowed parameter space compared to the pure scalar doublet DM limit. Presence of $Z_{2}$ -odd right-handed neutrinos also leads to other interesting phenomenology related to the origin of light neutrino masses and leptogenesis.
hep-phastro-ph.COhep-ex0 citations
41
Baryon number freeze-out in the Standard Model, precisely
Cristina Benso🇩🇪 · Dietrich Bödeker🇩🇪 · Kohei Kamada🇨🇳 · Kyohei Mukaida🇯🇵 · Laura Sagunski🇩🇪 · Philipp Schicho🇨🇭 · Kai Schmitz🇩🇪
Weak sphaleron transitions turn a lepton asymmetry of the Standard Model plasma in the early Universe into a baryon asymmetry, conserving baryon-minus-lepton number $B - L$ and its individual flavored charges. A baryon asymmetry can thus also arise from flavored lepton asymmetries with vanishing $B - L$ . Standard equilibrium calculations in the symmetric and broken phases are performed at constant temperature and hence neglect the fact that both the Higgs expectation value and the sphaleron rate vary as functions of temperature across the electroweak crossover. We derive a Boltzmann equation for the baryon number evolution across the crossover and calculate the freeze-out abundance including higher-order corrections to both the grand canonical partition function and the perturbative Higgs expectation value. This yields two sphaleron conversion factors: $C_{sph} = 0.3328 (5)$ for $B - L$ and $F_{sph} = 0.0279 (19)$ for the flavored charges weighted by the charged-lepton Yukawa couplings.
hep-ph0 citations
42
Gravitational Wave in an $A_{4} \otimes Z_{4}$ Neutrino Model with Generalised CP
Pulakesh Borah🇮🇳 · Mrinal Kumar Das🇮🇳
We extend the Standard Model with an $A_{4} \times Z_{4}$ flavor symmetry and generalized CP (GCP) symmetry, realized through two flavon triplets that spontaneously break $A_{4}$ and generate the observed lepton mixing pattern. A new $A_{4}$ -singlet flavon couples to one of these triplets through a complex quartic interaction that breaks GCP and fixes the reactor mixing angle; this same coupling biases the domain walls formed when that triplet breaks $A_{4}$ . A global fit to oscillation data reproduces all mixing angles and mass splittings, predicting a maximal Dirac CP phase of $27 0^{\circ}$ and an effective Majorana mass near $15 meV$ , testable by upcoming neutrinoless double-beta-decay ( $0 ν β β$ ) experiments. The same coupling generates a stochastic gravitational-wave background peaking in the pulsar-timing-array and LISA bands, with peak frequency and amplitude predicted to scale as $sin θ_{13}$ and $sin^{- 4} θ_{13}$ , a falsifiable link between neutrino oscillation and gravitational-wave (GW) observations.
hep-ph0 citations
43
Boosted dark particles and the LZ nuclear recoil event
Kristjan Kannike🇪🇪 · Martti Raidal🇪🇪 · Alessandro Strumia🇮🇹
The LZ experiment reported one anomalous event with nuclear recoil energy of 248 keV. Galactic halo dark matter (DM) cannot produce such a large energy unless heavier than 74 GeV, and heavy DM with spin-independent interactions would have produced unseen recoils at lower energy. Inelastic DM has been proposed as a way out. We consider, instead, an elastic collision of a dark sector particle with a momentum of at least 123~MeV and mass in the range 1-74 GeV as deuteron break-up in SNO disfavors sub-GeV masses. The absence of accompanying lower-energy recoils favours interactions whose rate grows with the momentum transfer, such as a pseudoscalar-pseudoscalar nucleon operator. This implies no leading-order signal in argon, an annual modulation below 1 %, and recoils in spinful light nuclei where inelastic halo DM gives nothing.
hep-ph0 citations
44
Inelastic Singlet-Doublet Fermion Dark Matter in light of the 248 keV LZ event
Debasish Borah🇮🇳 · Sujit Kumar Sahoo🇮🇳 · Narendra Sahu🇮🇳 · Shashwat Sharma🇮🇳
Recently, the LUX-ZEPLIN (LZ) collaboration reported the observation of a single dark matter (DM)-nucleus scattering event at a nuclear recoil energy of $248 \pm 2 3_{stat} \pm 2 3_{sys}$ keV, corresponding to an exposure of 2.84 tonne-year. The absence of events at lower nuclear recoil energies in the predicted spectrum is naturally explained if the underlying process is inelastic DM-nucleus scattering. Motivated by this, we investigate the singlet-doublet fermion DM model, in which the DM consists of two pseudo-Dirac states: the Majorana nature of the lighter state forbids tree level $Z$ -mediated elastic scattering identically, while the same states enable inelastic DM-nucleus scattering via $Z$ exchange, with any residual elastic scattering proceeding only through a suppressed Higgs-mediated channel. We further extend the model with a $Z_{2}$ -even scalar triplet, which is responsible both for generating the pseudo-Dirac splitting and for realizing Majorana neutrino masses via the Type-II seesaw mechanism.
hep-phastro-ph.COhep-exhep-th0 citations
45
Not so good $ν$ s for Higgsino dark matter as LZ excess: stringent limits from Super-Kamiokande and IceCube
Debajit Bose🇮🇳 · Akash Kumar Saha🇮🇳 · Deep Jyoti Das🇮🇳 · Rinchen Sherpa🇮🇳 · Abhijeet Singh🇮🇳 · Durba Ghosh🇮🇳 · Jaya Doliya🇮🇳 · Subhadip Bouri🇮🇳 · Biprajit Mondal🇮🇳 · Ranjini Mondol🇮🇳 · Nirmal Raj🇮🇳 · Ranjan Laha🇮🇳
The LUX-ZEPLIN (LZ) collaboration has recently reported a single nuclear recoil event at a high recoil energy of about 250 keV. This has been interpreted as inelastic scattering of dark matter that is a supersymmetric Higgsino with a mass splitting between the neutral states of a few 100 keV. Such dark matter may be captured at high recoil in the Sun through scattering on heavy elements in it, and annihilate to $W^{+} W^{-}$ and $Z Z$ , in turn giving rise to a neutrino flux detectable on Earth. Using measurements of atmospheric electron- and muon-neutrino fluxes by Super-Kamiokande and IceCube, we constrain thermal and non-thermal Higgsino dark matter, excluding inter-state mass splittings $≲ 557$ keV. This disfavors Higgsino-like interpretations of the LZ event for standard halo velocities.
hep-ph0 citations
46
Higgsino Dark Matter Interpretation of the LZ High-Recoil Event in the GNMSSM with TeV-Scale Gauginos
Subhadip Bisal🇨🇳 · Junjie Cao🇨🇳 · Fei Li🇨🇳
The nuclear recoil event at approximately 248 keV reported by the LUX-ZEPLIN collaboration motivates an investigation of endothermic dark matter scattering. We study this within the General Next-to-Minimal Supersymmetric Standard Model (GNMSSM), with Higgsino-dominated neutralino DM undergoing the $Z$ -mediated transition $χ_{1}^{0} N \to χ_{2}^{0} N$ . In the conventional thermal Higgsino limit of the MSSM, the observed relic abundance selects a mass near 1.1 TeV, while a neutralino splitting of a few hundred keV typically requires gaugino masses of order $1 0^{7}$ GeV. In the GNMSSM, Higgsino-Singlino mixing introduces an additional contribution to the splitting that can cancel the gaugino-induced contribution, allowing sub-MeV splitting with multi-TeV gauginos. This mixing also modifies the inelastic scattering coupling and annihilation rates, while coannihilation with sleptons provides freedom in obtaining the observed relic abundance. We present six benchmark points with dark-matter masses of 0.66-1.11 TeV, neutralino splittings of 333-350 keV, and gaugino masses of 2-5 TeV. These points reproduce the observed relic abundance and satisfy direct-detection, Higgs, flavor, and collider constraints. Within the Standard Halo Model and extended-likelihood analysis, all six points yield $Δ χ^{2} < 1$ relative to the best fit. Our results show how the GNMSSM can accommodate the LZ high-recoil event without an ultraheavy gaugino sector. A quantitative assessment of solar-capture and neutrino-telescope constraints remains necessary for establishing viability.
hep-ph0 citations
47
Quantum-Geometric Meissner Effect in Magnetized Color Superconductors
Kazuya Mameda🇯🇵 · Noriyuki Sogabe🇯🇵
We find a quantum-geometric Meissner response in magnetized two-flavor color-superconducting (2SC) quark matter. Landau quantization quenches the transverse quasiparticle dispersion, suppressing the conventional Fermi-surface contribution and giving rise to a Meissner response governed by the quantum geometry of the Landau levels. In the strong-field regime, the response becomes dominated by the quantum metric of the lowest Landau level (LLL), and the leading scaling of the transverse Meissner mass is consequently set by the pairing gap, in contrast to the chemical potential scaling of conventional color superconductors. This unconventional scaling has a topological origin, as the LLL quantum metric is constrained by its Chern number. The reduced transverse Meissner mass provides potential implications for kHz quasi-periodic oscillations in magnetars.
hep-phcond-mat.str-elcond-mat.supr-connucl-th0 citations
48
Initial momentum anisotropies in the kT-factorization of the CGC I: Gradient Expansion
Oscar Garcia-Montero🇪🇸
We revisit single-inclusive gluon production in the dilute--dilute limit of the Color Glass Condensate and show that $k_{⊥}$ -factorization is only the zeroth order of a systematic gradient expansion in the transverse positions of the two colliding sources, organized in powers of $1/ (Q_{s} R)$ , with $Q_{s}$ the saturation scale and $R$ the size over which the sources vary. Collecting terms order by order builds a ladder of scalar and tensor structures from the local distributions and their transverse derivatives, yielding an extended $k_{⊥}$ -factorized formula that retains the spatial dependence of the sources and, through kinetic moments of the spectrum, the energy-momentum tensor. Repeating the expansion from a real-time computation of the classical Glasma fields in the future light cone reproduces the momentum-space result in the eikonal limit, but additionally retains coherent interference between amplitude and conjugate. This adds terms to the ladder (flow responses, chromo-electric--magnetic interference, and a longitudinal energy flux) further suppressed by powers of the large outgoing momentum $∣ \pp ∣ ≫ Q_{s}$ . The hierarchy thus reveals momentum-space anisotropies present in the initial state before any hydrodynamic evolution, which leading $k_{⊥}$ -factorization misses by construction. Since each order is a local operator on the same unintegrated distributions, these corrections can be added directly to existing saturation-based initial-state models, giving a dynamically generated initial momentum anisotropy and a more faithful early-time energy-momentum tensor without abandoning the tractable factorized form. Set by gradients of the transverse density profiles, they grow towards more dilute, fluctuation-dominated systems, e.g. light-ion collisions. Phenomenological consequences will be developed in a companion paper.
hep-phnucl-th0 citations
49
Recent applications of the gradient flow
R. Harlander🇩🇪 · A. Shindler🇩🇪
The gradient flow provides a gauge- and O(4)-invariant ultraviolet regulator for QCD. This opens new opportunities for combining non-perturbative lattice calculations with perturbative results, in particular in the context of an operator-product expansion (OPE). We review the concepts behind this and argue that, within the operator basis of a given OPE, the flow-time dependence of the conversion between flowed and regular Wilson coefficients is exact at each perturbative order. Recent applications to parton distribution functions, heavy-meson observables, quark masses, and gradient-flow definitions of the strong coupling are discussed. Finally, the perturbative formulation of the Ricci flow in quantum gravity and its application to the study of non-Gaussian fixed points is reviewed.
hep-ph0 citations
50
Revisiting two-body charmed anti-charmed baryonic $B$ decays
Chun-Khiang Chua
The study of two-body charmed anti-charmed baryonic $B \to B_{c} B_{c}$ decays using the topological amplitude approach is revisited. We include the $b \to u u ˉ q$ contributions, in addition to the $b \to c c ˉ q$ contributions, to these decays. The topological decomposition of $B \to B_{c} (3 ˉ_{f}) B_{c} (3_{f})$ , $B_{c} (6_{f}) B_{c} (3_{f})$ , $B_{c} (3 ˉ_{f}) B_{c} (6 ˉ_{f})$ and $B_{c} (6_{f}) B_{c} (6 ˉ_{f})$ decay amplitudes are updated accordingly. Although the $b \to u u ˉ q$ contributions are CKM suppressed in $Δ S = - 1$ transitions, their effects are significantly amplified in $Δ S = 0$ transitions, as the relative size of the CKM factors in $b \to u u ˉ q$ and $b \to c c ˉ q$ contributions in $Δ S = 0$ transitions is enlarged by $λ^{- 2}$ , roughly a factor of 20, from the one in $Δ S = - 1$ transitions. Present data in $B \to B_{c} (3 ˉ_{f}) B_{c} (3_{f})$ decay rates allow or even slightly prefer non-negligible $b \to u u ˉ q$ contributions. These $b \to u u ˉ q$ contributions can allow much larger rates for $B^{-} \to Ξ_{c}^{0} Ξ ˉ_{c}^{-}$ , $B_{s}^{0} \to Λ_{c}^{+} Ξ ˉ_{c}^{-}$ and $B^{0} \to Ξ_{c}^{+} Ξ ˉ_{c}^{-}$ decays than those only have $b \to c c ˉ d$ contributions. Measuring these decays will be interesting and useful in clarifying the role of $b \to u u ˉ q$ contributions in two-body charmed anti-charmed baryonic $B \to B_{c} B_{c}$ decays.
hep-phhep-ex
51
Near-Threshold Dynamics of ḩi}c1(3872) and T+cc(3875) States via Effective Range Expansion and Monte Carlo Uncertainty Propagation
A. A. Atangana Likéné🇨🇭 · A. Franck Rothen🇨🇭 · J. M. Ema'a Ema'a🇨🇲 · P. Pradyun Hebbar🇨🇭 · Saralees Nadarajah🇬🇧 · Tobias Golling🇨🇭 · G. H. Ben-Bolie🇨🇲
We investigate the near-threshold structure of the exotic tetraquark candidates $χ_{c 1} (3872)$ and $T_{cc}^{+} (3875)$ using the effective-range expansion (ERE) and resonance compositeness relations. From the experimental masses and widths, we extract scattering lengths, effective ranges, and molecular compositeness coefficients within a two-channel framework, with uncertainties propagated through $N = 50000$ Monte Carlo samples. We find large negative scattering lengths, $a = - 8.4 9_{- 1.05}^{+ 0.93}$ fm for $χ_{c 1} (3872)$ and $a = - 14.5 7_{- 1.66}^{+ 1.70}$ fm for $T_{cc}^{+}$ , and dominant molecular components $X_{2} > 0.95$ . The results are robust against variations of compositeness, experimental correlations, and the loop-function subtraction constant. An explicit ERE+CDD-pole analysis finds no physically reasonable bare-state contribution consistent with the observed poles and a natural background. Our results provide strong evidence for predominantly molecular structures of both states and demonstrate the robustness of the ERE approach to near-threshold exotic hadrons.
hep-ph0 citations
52
Probing the $B^{0}$ meson in a hot medium with finite baryon chemical potential
A. Türkan🇺🇸 · G. Bozkır🇹🇷 · K. Azizi🇮🇷
We perform a quantitative analysis of the $B^{0}$ meson spectroscopic parameters in a hot and dense medium. Within the framework of QCD two-point sum rules, we calculate the mass and decay constant of the $B^{0}$ meson with the help of the perturbative spectral density and nonperturbative contributions up to mass dimension five as functions of temperature $T$ and baryon chemical potential $μ_{B}$ . For various fixed values of the baryon chemical potential, our numerical results indicate that both the mass and decay constant of the $B^{0}$ meson initially increase with temperature, reach a maximum, and then gradually decrease before eventually vanishing at sufficiently high temperatures. The corresponding vanishing points are found to be in the temperature intervals $(0.182 - 0.273) GeV$ and $(0.118 - 0.173) GeV$ , for the mass and decay constant, respectively. Moreover, these temperatures move toward lower values as the baryon chemical potential increases. On the other hand, for various fixed temperatures, both the mass and decay constant exhibit a slight initial increase with increasing baryon chemical potential, followed by a subsequent decrease, eventually vanishing at sufficiently high chemical potentials. The vanishing points for the decay constant is determined to be in baryon chemical potential interval $(0.23 - 0.83) GeV$ . For the mass, the decrease at $T = 0$ is much weaker than at finite temperatures; excluding this case, the vanishing points for the mass are determined to be in baryon chemical potential interval $(0.38 - 1.43) GeV$ for different fixed temperatures. It is further observed that the baryon chemical potential values corresponding to the vanishing of both the mass and decay constant move to lower values as the temperature increases. In the $T \to 0$ and $μ_{B} \to 0$ limit ...
hep-phhep-exhep-lat0 citations
53
Top-quark flavor-changing neutral currents and charged-lepton flavor violation in a generational three-Higgs-doublet model
Hao-Ran Ma🇨🇳 · Ti-Bin Hou🇨🇳 · Yu-Ju Peng🇨🇳 · Jin-Lei Yang🇨🇳 · Tai-Fu Feng🇨🇳
In this work, we systematically investigate top-quark flavor-changing neutral-current decays, charged-lepton flavor-violating processes, and coherent $μ - e$ conversion in the CP-conserving generational three-Higgs-doublet model (G3HDM), including the relevant tree-level and one-loop contributions. The 4839-point sample passes conservative sufficient vacuum-stability conditions, necessary perturbative-unitarity preselection cuts, Higgs-mass and signal-strength constraints, electroweak precision data, the UTfit 2025 neutral-meson-mixing ranges, $B \to X_{s} γ$ , and $B_{s} \to μ^{+} μ^{-}$ . In the scanned region, $Br (t \to c h_{1}) \leq 1.04 \times 1 0^{- 5}$ and $Br (h_{1} \to μτ) \leq 4.83 \times 1 0^{- 4}$ , while the maximal conversion rates are $CR (μ Al \to e Al) \approx 4.95 \times 1 0^{- 15}$ and $CR (μ Au \to e Au) \approx 1.05 \times 1 0^{- 14}$ . The dominant collider signals are mainly driven by tree-level flavor-changing neutral-Higgs couplings, which determine the relative strengths of these processes and induce the pronounced enhancement of $t \to c h_{1}$ and $h_{1} \to μτ$ . Meanwhile, the upper range of the predicted $μ - e$ conversion rate in aluminum lies within the sensitivity reach of next-generation $μ - e$ conversion experiments.
hep-ph0 citations
54
Light cone distributions of $P$ -wave quarkonia
Yang Li🇨🇳 · Tianyang Hu🇨🇳 · Xianghui Cao🇨🇳 · Meijian Li🇪🇸
Motivated by renewed interest in the light-cone distributions of $P$ -wave quarkonia, we investigate the leading-twist distribution amplitudes of these states within the basis light-front quantization (BLFQ) formalism. While our extracted distributions exhibit macroscopic shapes consistent with expectations from the non-relativistic limit, we find that relativistic effects introduce critical structural features. Most notably, we observe novel ``W"-shaped structures in the distribution amplitudes of the axial vector mesons, which arise from relativistically induced $S / D$ partial waves and cannot be explained by non-relativistic dynamics. These findings provide essential non-perturbative inputs for analyzing hard exclusive processes and highlight the importance of relativistic frameworks for understanding heavy quarkonium production and structure at modern high-energy colliders.
hep-phnucl-th0 citations
55
Time evolution of scalar condensate decay
Ayuki Kamada🇵🇱 · Kodai Sakurai🇯🇵
A scalar field, which oscillates coherently over the space and decays through production of daughter particles, plays an important role in cosmology. It was recently shown that the parametric-resonance and Feynman-diagrammatic approaches give the same decay rate for a Bosonic daughter particle at a large time duration. We study how the parametric-resonance result approaches to this asymptotic value, by numerically following the time evolution of the phase density of the daughter particle. We see a difference among different instability bands in the narrow-resonance regime. The lowest-order instability band approaches to the Feynman-diagrammatic result in tens of scalar oscillation periods, while the high-order instability bands approach dependently also on a coupling between the scalar and daughter particles. This would infer that the total decay width, to which the lowest-order instability band contributes most dominantly in the perturbation theory, approaches to the Feynman-diagrammatic result also independently of the coupling. To confirm it, we consider a simpler and analytically solvable quantum mechanical model: Rabi models. In the Bosonic Rabi model, the parametric-resonance and Feynman-diagrammatic results agree with each other for all the time. On the other hand, in the Fermionic Rabi model, they disagree at a large time duration. This difference would be attributed to Bose enhancement vs Pauli blocking.
hep-ph0 citations
56
Inclusive electron-nucleus cross section models from domain adaptation
Krzysztof M. Graczyk🇵🇱 · Beata E. Kowal🇵🇱 · Rwik Dharmapal Banerjee🇵🇱 · Jose Luis Bonilla🇵🇱 · Hemant Prasad🇵🇱 · Jan T. Sobczyk🇵🇱
We apply transfer learning (TL) to construct data-driven models of inclusive electron-nucleus cross sections. Starting from an ensemble of deep neural networks pretrained on $^{12}$C data, we fine-tune the models separately for $^{3}$He, $^{6}$Li, $^{16}$O, $^{27}$Al, $^{40}$Ca, and $^{56}$Fe. The resulting models improve for all targets, marginally so for oxygen, where the carbon baseline is already adequate, although their predictive robustness depends on the amount, coverage, and precision of the available target data. We systematically study how model performance depends on the number of fine-tuned layers, on the fraction and selection of the training data, and on the overlap between the source and target kinematic domains. The layer-wise analysis shows that oxygen requires only shallow adaptation, whereas helium, calcium, and iron require substantially deeper fine-tuning. Lithium represents the least robust case because of its limited dataset, while aluminum demonstrates a strong sensitivity to a small subset of highly constraining measurements. For selected kinematic configurations outside the coverage of the carbon training data, the adapted models remain consistent with the measurements within their estimated uncertainties. Finally, we compare the resulting predictions with those of the phenomenological F1F2 model.
hep-phcs.LGhep-exnucl-ex+10 citations
57
Nonperturbative functional renormalization group for Higgs-singlet models with physics-informed neural networks
Norimi Yokozaki
We develop a nonperturbative functional renormalization group framework within the LPA' to solve the Wetterich flow equation for the $Z_{2}$ -symmetric real singlet extension of the Standard Model at zero and finite temperature, without a polynomial expansion of the scale-dependent effective potential, using a physics-informed neural network (PINN) representation. In contrast to conventional truncations based on low-order field expansions, our hybrid tree-level--plus--neural-network ansatz yields a continuous, mesh-free description of the effective potential over the full relevant field and scale range. As a proof of concept, we apply the framework to the finite-temperature effective potential relevant to the electroweak phase transition in this model: one-dimensional field-space slices at two benchmark temperatures, and a two-dimensional reconstruction at $T = 100$ GeV from which a two-step bounce action is extracted. The renormalization group flow is implemented in a multi-domain setup in scale and field space with derivative matching conditions that ensure smoothness and numerical stability. Gauge and Yukawa sectors are incorporated via independently computed perturbative two-loop running couplings, and anomalous dimensions are included in the flow at the LPA' level. We benchmark the network against resummed perturbation theory and against a grid-based relaxation solver of the same equation. Finally, we introduce a soft consistency constraint that keeps the solution close, in sign and order of magnitude, to perturbation theory across the field-space domain; we find it necessary, rather than merely helpful, for selecting a physically sensible solution of the flow equation, and find that the converged result retains a residual dependence on this guidance -- through hand-tuned weights and an analytic thermal target -- which we identify as the central open problem.
hep-phphysics.comp-ph
58
Gravitational transverse momentum dependent distributions for the gluons
Kauship Saha🇮🇳 · Dipansu Mishra🇮🇳 · Dipankar Chakrabarti🇮🇳 · Asmita Mukherjee🇮🇳
We investigate the momentum-space structure of the gauge-invariant gluon energy-momentum tensor (EMT) for spin- $0$ and spin- $\frac{1}{2}$ hadrons in the light-front formalism. We parameterize the nonlocal gluon EMT in terms of so-called gluon gravitational transverse-momentum-dependent distributions (gravitational TMDs) and derive their connections to twist-2 and twist-3 gluon TMDs. Moreover, we demonstrate that particular components of the gluon EMT encode information about the average kinetic four-momentum of gluons and the internal mechanical properties of hadrons-such as pressure and shear distributions.
hep-ph0 citations
59
A distance-independent constraint on the axion-electron coupling from RGB stars
Thomas Levasseur · Oscar Straniero · Andrea Caputo
Interest in axions and axion-like particles has resurged, driven by their role in solving the strong CP problem and their appeal as dark matter candidates. The luminosity of the tip of the red giant branch (TRGB) offers a key observable for probing these particle properties. This work aims to improve existing bounds on the axion-electron coupling by adopting a differential observable that is less sensitive to distance, interstellar extinction, the zero-point of bolometric corrections (BCs), and other systematic uncertainties. We use the bolometric magnitude difference between the TRGB and the RGB bump (RGBB) as a distance-independent constraint, applied to three globular clusters of intermediate-to-high metallicity: NGC 104 (47 Tuc), NGC 362, and NGC 5904 (M5). Using photometric catalogs of RGB stars, we determine V- and I-band magnitudes of both features and convert them to bolometric values. After validating that our stellar models reproduce the observed RGBB luminosity, we perform a maximum likelihood analysis with Monte Carlo simulations to propagate uncertainties and derive new bounds on the coupling. A combined analysis of the three clusters yields a maximum likelihood at g13 = gae/10^-13 = 0.8 and a 95% C.L. upper limit of 1.49. Although slightly less stringent than recent bounds from larger multi-cluster samples, this limit is substantially more robust. Under reasonable mass-loss assumptions, g13 > 7.5 is ruled out, as it predicts the disappearance of the HB and AGB phases routinely observed in globular clusters, a limit more than an order of magnitude stronger than current direct experimental bounds such as XENONnT. We demonstrate the effectiveness of this differential, distance-independent method for constraining physics beyond the Standard Model. Applying it to a wider sample of globular clusters would further refine the constraint on gae.
hep-phastro-ph.SR
60
Hot QCD: transport coefficients in strong and weak coupling regimes
Gabriele Parisi🇮🇹
We evaluate the transport coefficients, namely the shear viscosity $η$ and the spatial diffusion coefficient of heavy quarks $D_{s}$ , within a Quasi-Particle Model (QPM). In particular, for the first time this has been done by exploiting novel lQCD data at $N_{f} = 3 + 1$ . In such a framework, in which the gluons are massive, the interactions among quarks and gluons have been evaluated via the scattering matrices evaluated from tree level Feynman diagrams. As far as the evaluation of $D_{s}$ is concerned, the Fokker-Planck approximation for the relativistic Boltzmann equation has been employed for the diffusion of both charm and bottom quarks in either a $N_{f} = 3$ and a $N_{f} = 3 + 1$ bulk. We have developed a dual-component Chapman-Enskog formalism for the ratio $η / s$ (being $s$ the entropy density) of a mixture of quarks and gluons. The temperature dependence of the shear viscosity is then compared to the results from a Green-Kubo approach, based on the numerical resolution of the relativistic Boltzmann equation with a stochastic implementation of the collision integral. Finally, using the above results, we compare the strong and weak coupling regimes for the ratio $(2 π T D_{s}) / (4 π η / s)$ .
hep-ph0 citations
61
Free $μ^{+} μ^{-}$ and bound-free $e^{+} e^{-}$ pair production in relativistic heavy-ion collisions
Melek Yilmaz Şengül
In our previous studies, we calculated the cross-section for the production of free $μ^{+} μ^{-}$ pairs using a probability function dependent on the impact parameter, and also, we computed bound-free $e^{+} e^{-}$ pair production cross section. In this study, unlike the others, we obtained the cross section for the production of bound-free $e^{+} e^{-}$ pairs using the probability function dependent on the impact parameter. Here also, we simultaneously calculated the cross sections for producing free $μ^{+} μ^{-}$ with bound-free $e^{+} e^{-}$ pairs in relativistic $P b + P b$ collisions at the LHC with Lorentz factors at $γ = 1500$ and $γ = 3000$ reported in the literature. Our calculation is based on second-order perturbation theory, implemented by using Monte Carlo integration techniques. We present impact parameter dependent pair production probabilities for free $μ^{+} μ^{-}$ and bound-free $e^{+} e^{-}$ pair production processes. Notably, the bound-free $e^{+} e^{-}$ pair production was evaluated by using a formalism adapted from that of free $μ^{+} μ^{-}$ pair production. Our results obtained here for the free $μ^{+} μ^{-}$ with bound-free $e^{+} e^{-}$ pair production cross sections are compared with those from other theoretical methods available in the literature. This study aims to provide predictions that can be tested against future experimental data, thereby offering a valuable check for quantum electrodynamics (QED) in strong electromagnetic fields.
hep-ph
62
The transverse-spin asymmetry $A_{U U T}^{s i n ϕ_{S_{Λ}}}$ in $Λ$ production in SIDIS within the collinear framework
Yongliang Yang · Zhun Lu🇨🇳
We investigate the transverse-spin asymmetry $A_{U U T}^{s i n ϕ_{S_{Λ}}}$ for transversely polarized $Λ$ production in semi-inclusive deep inelastic scattering with an unpolarized electron beam and an unpolarized nucleon target. The spin-dependent asymmetry is sensitive to the twist-3 T-odd quark-gluon-quark fragmentation function $D ~_{T}$ , which describes the correlation between an unpolarized fragmenting quark and the transverse polarization of the produced hadron. We calculate $D ~_{T}$ of the $Λ$ hyperon within a diquark model and investigate its contribution to the asymmetry. We determine the model parameters by fitting the fragmentation functions $D_{1}$ and $G_{1}$ to the DSV parametrization. Using the numerical results of the model and the available parametrization of the unpolarized parton distribution function $f_{1}$ , we predict the asymmetry in the electroproduction of the $Λ$ hyperon in the kinematic regions of the EIC and the EicC. We also examine the impact of including the strange-quark contribution on the transverse-spin asymmetry. In our phenomenological analysis, we include the QCD evolution of the parton distribution function $f_{1}$ and the fragmentation function $D ~_{T}$ . The results show that the asymmetry is sizable and can be significantly modified by the strange-quark contribution.
hep-ph0 citations
63
From LUX-ZEPLIN to Colliders: Probing Higgsino Dark Matter
Kingman Cheung🇹🇼 · Sin Kyu Kang🇰🇷 · Ranjeet Kumar
The high-energy nuclear recoil event with recoil energy $E_{R} \approx 248 keV$ observed by the LZ collaboration provides an exciting hint toward a model with a $1.1 TeV$ Higgsino inelastic dark matter. Such a recoil energy requires a mass splitting of order ( $δ \approx 350 keV$ ) between the two nearly-degenerate neutral states. We show that within the framework of the MSSM, the model predicts a nearly-degenerate charged Higgsino state, chargino, whose mass splitting from the neutral states is of order $O (350)$ ~MeV. The subsequent decays of such charginos once produced at colliders would lead to a sub-centimeter charged track or tracklet (with lifetime $τ \approx 0.025 ns$ ) at the detector. We show that such a scenario is not constrained by the current LHC bounds, and could be tested at future high-energy colliders, including HL-LHC, 100 TeV $pp$ colliders, and muon colliders. The most critical requirement is how short a track or tracklet can be reconstructed.
hep-ph0 citations
64
Backward Compton scattering with three vortex particles
Yi Liao🇨🇳 · Zhaolong Teng🇨🇳 · Hao-Lin Wang🇨🇳
We investigate backward Compton scattering in which an incident vortex (vx) photon collides head-on with a plane-wave (pw) electron and both final-state particles are projected onto vortex states, $γ_{vx} + e_{pw}^{-} \to γ_{vx} + e_{vx}^{-}$ . We derive analytically the scattering amplitude and differential cross sections in the energy and cone angle of either final particle. Rotational symmetry implies a selection rule associated with the conservation of the total angular momentum along the collision axis. A Bessel-Gaussian wave packet is adopted for the incident photon to provide a physical normalization and regularize the boundary singularities of ideal Bessel states. We present numerical results for a $10 MeV$ electron colliding with a vortex photon of central energy $1 MeV$ or $10 keV$ . The final-photon distributions exhibit strong energy--angle correlations, topological-charge-dependent interference fringes, and systematic shifts of their dominant peaks, allowing different topological charge sectors to be enhanced through angular or energy post-selection. For a longitudinally polarized incident electron, the dominant channels favor final photons of matching helicity. For the $1 MeV$ photon benchmark, the final electron can likewise be produced as a MeV-scale vortex state with a sizable cone angle and a large angular-momentum projection. These results demonstrate that triple-vortex backward Compton scattering offers a potential means of generating and controlling high-energy vortex photons and electrons.
hep-phphysics.atom-phphysics.optics0 citations
65
Theory updates for parton distributions in Hessian formalism
Petja Paakkinen🇫🇮 · Hannu Paukkunen🇫🇮 · Sami Yrjänheikki🇫🇮
We present a new extension to the toolbox of parton-distribution reweighting methods, which enables a general user to study the impact of an updated theory prediction on the results of a pre-existing parton-distribution global analysis. This new method is a combination of the well-known reweighting method with a new deweighting variant where a dataset is removed from the original analysis in an approximate way. Specific use cases of this method could include e.g. testing the impact of updating the treatment of an observable from N $^{n}$ LO to N $^{n + 1}$ LO precision in the global analysis, or including previously ignored electroweak, mass, resummation, or higher-twist effects, or even testing the impact of some beyond-standard-model physics. We discuss the implementation of this method in the Hessian formalism, and show its use in a single case study, where we update the treatment of dimuon production in neutrino-induced DIS with the novel semi-inclusive DIS approach.
hep-ph0 citations
66
Chiral matching of dimension-7 baryon-number-violating operators and application to $Δ I = 3/2$ nucleon decays
Xiao-Dong Ma🇨🇳
We study chiral matching of dimension-7 (dim-7) baryon-number-violating operators in low-energy effective field theory. We show that all dim-7 operators can be classified into two distinct Lorentz structures and their chirality-flipped counterparts, and we derive their leading-order hadronic realizations in chiral perturbation theory. As an application, we systematically investigate $Δ I = 3/2$ nucleon decays, including $n \to ℓ^{-} π^{+}$ , $p \to ℓ^{-} π^{+} π^{+}$ , and $n \to ℓ^{-} π^{+} (π^{0}, η)$ , with $ℓ = e, μ$ . Using existing experimental bounds on $n \to ℓ^{-} π^{+}$ , we set stringent constraints on the relevant Wilson coefficients and derive improved lower limits on the partial lifetimes of the six three-body modes from their correlations with the two-body modes. We further present a concrete ultraviolet model that generates the dim-7 operators and the associated $Δ I = 3/2$ nucleon decays at leading order. Our results pave the way for exploring dim-7 contributions to nucleon decays and motivate future searches for these exotic modes.
hep-ph0 citations
67
Neutrino mass, scalar dark matter, and collider signatures in a radiative doublet-triplet model
Isaac Bamwidhi🇦🇪 · Mohamed Belfkir🇦🇪 · Mohamed Amin Loualidi🇦🇪 · Salah Nasri🇦🇪
We explore a radiative neutrino mass model based on the topology T4-3-i, which is a one-loop completion of the Weinberg operator. We focus on its T4-3-i-C1 realization, containing an inert scalar doublet, a real scalar triplet, a Majorana fermion triplet, and a Dirac singlet fermion. An exact $Z_{2}$ symmetry forbids the tree-level type-III term and stabilizes the lightest $Z_{2}$ -odd particle, leaving the one-loop topology as the leading source of neutrino mass. The model accomodate a neutral {\it CP}-even scalar dark matter candidate and predicts a rank two neutrino mass matrix, and thus one neutrino is massless. A combined analysis incorporating theoretical and experimental constraints reveals viable solutions to both neutrino mass orderings, with the inverted ordering predicting larger values of $m_{β β}$ , $m_{β}$ , and $\sum_{i} m_{i}$ , thereby enhancing its testability through future beta-decay, neutrinoless double beta decay, and cosmological probes. Within the same viable parameter region, the observed dark matter relic abundance is accounted for by annihilation and coannihilation processes, while the electroweak triplet sector gives rise to prompt, displaced, or long-lived particle signatures, offering complementary collider probes to dark matter and low-energy searches.
hep-ph0 citations
68
Axion Hair and Pulsar Electrodynamics: modelling, discharge dynamics, and particle-in-cell simulations
Samuel J. Witte🇬🇧 · Andrea Caputo🇨🇭 · Stefan Stelzl🇨🇭 · Alexander Chernoglazov🇺🇸 · Alexander A. Philippov🇺🇸 · Surjeet Rajendran🇺🇸
In a companion paper, we demonstrated that static axion field gradients sourced by dense nuclear matter (\emph{axion hair}) can dominate the near-field electrodynamics of old rotation-powered pulsars, leading to new constraints on light QCD axions and on CP-violating axion-nucleon interactions. This article provides the extended theoretical and numerical framework underlying those results. We begin by providing a detailed description of the sourcing of axion hair from dense nuclear matter, computing self-consistent field profiles for each interaction across the relevant parameter space. We then study the modification to the electrodynamics induced in the polar gap region by these axion gradients; this is done at the analytic level by studying the modification induced by axion field gradients on the effective discharge parameter (computed in the force-free limit of the split monopole magnetic field configuration, and looking at leading deviations from the force-free limit for dipolar field configurations), and numerically by developing dedicated 1D particle-in-cell simulations which capture the leading order dynamical behavior near the star. Our results demonstrate that axion hair serves to either enhance acceleration, or enhance screening, where the relevant effect changes between the northern and southern hemispheres of the star, and between the field lines which support out-flowing and return currents.
hep-phastro-ph.HE0 citations
69
How to choose a good rational basis for elliptic Feynman integrals?
Ekta Chaubey🇩🇪 · Vasily Sotnikov🇨🇭
Representing multi-loop scattering amplitudes as linear combinations of multivalued transcendental functions with process-dependent rational coefficients has long been understood to be advantageous. In general, these transcendental functions satisfy a system of differential equations with coupled homogeneous blocks. When these coupled blocks can be removed through algebraic basis transformations, the relation between the rational and algebraic bases is universal and minimal. Here, we ask whether an analogous universal and minimal relation exists when decoupling requires transformations involving complete elliptic integrals. We elaborate on the method proposed in ref. arXiv:2504.20897, in which we suggested that a basis constructed using an elliptic generalization of leading singularities may provide an answer to this question. We extend this analysis to the off-diagonal blocks of the rational differential equations satisfied by the bases obtained through this construction. We find that the $ϵ$ dependence of these blocks can be organized into a universal structure that is preserved under the decoupling transformation used to express the solutions in terms of iterated integrals.
hep-phhep-th0 citations
70
ALP-mediated inelastic dark matter and the LUX-ZEPLIN high-recoil candidate event LZ230616
Guan-Wen Yuan🇮🇹 · Bo Zhang🇨🇳 · Wen-Yu Cao🇨🇳 · Lei Feng🇨🇳 · Ruizhi Yang🇨🇳
The LUX-ZEPLIN (LZ) Collaboration has reported a high-energy candidate event LZ230616 with a reconstructed nuclear recoil energy $E_{R} = 248 \pm 2 3_{stat} \pm 2 3_{sys} keV$ . We investigate a possible interpretation in terms of inelastic scattering between two Majorana dark matter states mediated by an axionlike particle coupled to gluons. The positive mass splitting suppresses low-energy recoils, while the momentum dependence of the interaction reshapes the high-energy spectrum. We treat the dark-sector and gluonic couplings independently and retain the momentum-dependent nucleon form factors and xenon nuclear responses. Using an approximate single-event likelihood, we find that, for $m_{a} = 0.3 GeV$ , a narrow spectrum near the candidate energy arises at $m_{χ} ≃ 0.35 TeV$ and $δ ≃ 330 keV$ , although this configuration requires a large coupling product and is highly sensitive to the Galactic halo speed cutoff. Our analysis establishes the kinematic and coupling requirements for subsequent tests using the thermal relic abundance and laboratory constraints on the mediator.
hep-ph0 citations
71
Relativistic spatial distributions of transverse angular momentum
Cédric Lorcé · Asmita Mukherjee · Ravi Singh · Ho-Yeon Won
In our previous work [C. Lorcé et al., Phys. Lett. B 868 (2025) 139792], we investigated the 2D spatial distributions of transverse total angular momentum, including orbital angular momentum and intrinsic spin, relative to the canonical center (or center of spin). In the present work, we extend this analysis in two directions. First, we study the corresponding transverse boost distributions relative to the canonical center. Second, since the definition of generalized angular momentum density depends crucially on the choice of pivot, we analyze how the spatial distributions of transverse total angular momentum and boost are modified when they are defined relative to different relativistic centers, viz.~the relativistic centers of mass, energy, and spin. Considering spin-1/2 targets, we derive the corresponding 2D spatial distributions in the transverse plane, and further investigate how the spatial patterns evolve under longitudinal Lorentz boosts. Additionally, we provide the corresponding light-front distributions in the transverse plane, establishing a clear connection between the instant-form and light-front descriptions of transverse angular momentum and boost.
hep-phhep-thnucl-th
72
Probing the Inert Scalar Sector of the Inert Doublet Model via Vector-Boson Fusion at a Muon Collider
Abdesslam Arhrib🇲🇦 · Es-said Ghourmin🇲🇦 · Ayoub Hmissou🇲🇦 · Larbi Rahili🇲🇦 · Bassim Taki🇲🇦
We investigate the sensitivity of a future high-energy muon collider (MuCs) to the inert scalar sector of the Inert Doublet Model (IDM) through a comprehensive set of $2 \to 4$ electroweak gauge-boson fusion processes. The scalar spectrum consists of two CP-even neutral scalars: $h$ and $H$ , one CP-odd neutral scalar $A$ , and a pair of charged scalars $H^{\pm}$ . We assume the neutral scalar $H$ to be the lightest inert state and the dark matter (DM) candidate, while the observed $125$ ~GeV Higgs boson is identified with the scalar of the Standard Model-like doublet. We consider charged Higgs pair production: $μ^{+} μ^{-} \to H^{+} H^{-} ν ν ˉ$ induced by WW fusion, as well as the associated channels: $μ^{+} μ^{-} \to H H^{\pm} μ^{\mp} ν$ and $μ^{+} μ^{-} \to A H^{\pm} μ^{\mp} ν$ , induced by $W Z$ and $W γ$ fusion. Owing to their Vector Boson Fusion (VBF) origin, the corresponding cross sections increase significantly with collider energy, making them particularly well suited for exploration at a high-energy MuCs. We first study the $2 \to 2$ subprocesses $W W \to H^{+} H^{-}$ and $W V \to H^{+} S_{i}$ , $V = Z, γ$ and $S_{i} = H$ or $A$ and establish the destructive interference among the contributing diagrams. After imposing theoretical consistency requirements and current experimental constraints, including those from DM and collider searches, we evaluate the corresponding signal rates at $s = 3$ , $10$ , and $20$ ~TeV. We further perform a detector-level Monte Carlo analysis combined with a cut-based signal-background selection. Our results demonstrate that the sensitivity to inert scalar production increases significantly with collision energy, establishing the 10 and 20~TeV MuCs stages as powerful probes of the IDM inert scalar sector.
hep-ph0 citations
73
A Vector-Like Lepton Interpretation of the High-Energy Nuclear Recoil Candidate in LUX-ZEPLIN
Fatemeh Elahi🇩🇪 · Pedro Schwaller🇩🇪
The LUX-ZEPLIN (LZ) experiment has recently reported a nuclear-recoil candidate at $E_{R} = 248 \pm 2 3_{stat} \pm 2 3_{sys} keV$ in an exposure of $2.84 tonne yr$ . At this unusually high recoil energy, the spin-independent (SI) xenon response is strongly suppressed, motivating dark matter interactions with a harder recoil spectrum. We show that elastic spin-dependent (SD) scattering through the nonrelativistic operator $O_{4} = S_{DM} \cdot S_{N}$ provides a simple realization of such a spectrum. We consider singlet-doublet Majorana dark matter, for which a diagonal $Z$ coupling generates the required SD interaction. The accompanying Higgs-mediated SI interaction would generically produce too many low-energy recoils, but can be suppressed along a Higgs blind spot while retaining a nonzero $Z$ coupling. We find a region of the Higgs blind spot that simultaneously predicts an $O (1)$ event rate in the LZ high-recoil window and reproduces the observed thermal relic abundance. The same SD interaction leads to solar capture, allowing this region to be tested independently with solar-neutrino searches. Current IceCube limits already probe part of the LZ-compatible thermal parameter space, while a viable region remains. Additional xenon exposure and improved solar-neutrino searches can therefore provide complementary tests of this interpretation.
hep-phastro-ph.COastro-ph.HEhep-ex0 citations
74
Final-state effects on the transverse-momentum spectra of charged hadrons in $p + P b$ and $P b + P b$ collisions at $s_{NN} = 5.02$ ~TeV using the modified Tsallis distribution
Kapil Saraswat🇹🇼 · Deependra Singh Rawat🇮🇳 · Manoj Kumar Singh🇹🇼 · Prashanta Kumar Khandai🇮🇳 · Damini Singh🇮🇳 · Venktesh Singh🇮🇳
The ATLAS Collaboration has reported measurements of the transverse momentum ( $p_{T}$ ) spectra of charged hadrons in proton-proton ( $p + p$ ), proton-lead ( $p + P b$ ), and lead-lead ( $P b + P b$ ) collisions at a nucleon-nucleon center-of-mass energy of $s_{NN} =$ ~5.02~TeV within the rapidity interval $- 2.5 < y < 2.0$ . In the present work, we investigate medium effects on charged-hadron production in $p + P b$ and $P b + P b$ collisions using a phenomenological modified Tsallis parametrization that accounts for transverse collective flow in the low-to-intermediate $p_{T}$ region and medium-induced parton energy loss at high $p_{T}$ . The modified parametrization provides a consistent description of the measured spectra over the full investigated $p_{T}$ range across different centrality classes. The extracted energy-loss exponent $α$ , which characterizes the energy dependence of parton energy loss, is found to lie in the range 0.59 $-$ 0.73 for $p + P b$ collisions and 0.32 $-$ 0.59 for $P b + P b$ collisions. In addition, the extracted parameters exhibit a clear centrality dependence, reflecting enhanced collective effects in central collisions. These results provide quantitative insight into the interplay between transverse collective flow and medium-induced parton energy loss in charged-hadron production at LHC energies.
hep-ph0 citations
75
Endothermic dark matter with a light dark photon and the LUX--ZEPLIN high-energy nuclear-recoil candidate
Pengxuan Zhu🇦🇺 · Giovani Dalla Valle Garcia🇩🇪 · Xuan-Gong Wang🇦🇺 · Anthony W. Thomas🇦🇺 · Martin J. White
The LUX-ZEPLIN (LZ) experiment has reported a single nuclear-recoil candidate at $E_{nr} = 248 \pm 2 3_{stat} \pm 2 3_{sys} keV$ . We investigate whether this event can be explained by endothermic inelastic dark matter coupled to a kinetically mixed dark photon, while reproducing the observed dark-matter relic abundance. Performing a global scan of the five model parameters, combining an energy-only recast of the LZ high-energy likelihood with a relic-density likelihood, we find a preferred region with TeV-scale dark matter masses, mass splittings of a few hundred keV, and a GeV-scale dark photon. The high recoil energy requires the splitting to lie close to the kinematic threshold, so that the signal is supplied by the high-velocity tail of the halo, while the secluded annihilation mechanism fixes the dark gauge coupling, largely independently of the kinetic mixing. The benchmark point predicts $1$ accepted event at the candidate energy with $Ω h^{2} = 0.120$ . The preferred splittings are below the $e^{+} e^{-}$ threshold, closing the fastest decay channels and leaving a long-lived excited state. Its surviving population is subject to stringent cosmological constraints from energy injection and can also produce an additional exothermic scattering signal, making the late-time abundance an important consistency condition for the minimal model. A dimension-five transition dipole provides a simple way to efficiently deplete $χ_{2}$ without modifying either the relic abundance or the endothermic LZ signal. The corresponding light-dark-photon scenario remains testable in accelerator searches, including future LHCb, Belle II, and SHiP experiments.
hep-ph0 citations
76
Neutron disappearance and the LZ nuclear recoil event
Mohammad Aghaie🇯🇵 · Alessandro Strumia🇮🇹
The LZ experiment reported a nuclear recoil with anomalous energy $E_{R} = 248$ keV, around the typical neutron motion in xenon. This motivates interpreting the event as the disappearance of a bound neutron, either through spontaneous decay or a dark-matter-induced reaction. If the energy released is large, the predicted recoil spectrum is broad around the observed value; only $\sim 10%$ of xenon events avoid extra nuclear activity; the disappearance rate is target-independent and mildly constrained by oxygen experiments. In the special case of near-threshold DM-induced neutron disappearance, it can be open in xenon and closed in oxygen, the quiet fraction rises to $\sim 30%$ , the recoil spectrum turns into lines.
hep-phhep-ex0 citations
77
Bottomonium suppression with a machine-learning-informed Debye mass
Ajaharul Islam🇨🇳 · Shibo Chen🇨🇳 · Fu-Peng Li🇨🇳 · Long-Gang Pang🇨🇳 · Guang-You Qin🇨🇳
Motivated by recent progress in data-driven approaches, we introduce a machine-learning (ML)-informed Debye mass, extracted from lattice-informed inputs, exclusively in the complex-valued heavy-quark Kent State University (KSU) potential. The resulting complex potential is used to solve the real-time Schrödinger equation within the quantum trajectories (QTraj) framework for the evolution of bottomonium in the quark-gluon plasma. We then compute the nuclear modification factors and double ratios for bottomonium $Υ (1 S)$ , $Υ (2 S)$ , and $Υ (3 S)$ states in Pb-Pb collisions at $s_{N N} = 5.02$ TeV. We compare our ML-induced results with those from the original KSU model and with experimental measurements from ALICE, ATLAS, and CMS collaborations. We find that the machine-learned Debye mass leads to improved agreement with data, particularly for excited states, highlighting the utility of machine learning in modeling in-medium QCD effects.
hep-phhep-exnucl-exnucl-th0 citations
78
Two-Loop Anomalous Dimension for Non-Global and Clustering Logarithms
Thomas Becher🇨🇭 · Jürg Haag🇨🇭 · Nicolas Schalch🇬🇧
We derive the two-loop anomalous dimension relevant for the resummation of subleading non-global and, for the first time, also clustering logarithms within the framework of effective field theory. Special emphasis is put on the choice of the renormalization scheme. We show that the modified minimal subtraction scheme is problematic since it requires extra dimensions to set up the parton shower to perform the resummation. We discuss a set of modified dipole subtraction schemes which are free from this complication and can be used to obtain a frame-independent result for the renormalization-group evolution. We implement the leading-color limit of our result in the Marzili framework and numerically verify the scheme independence for gap-between-jets cross sections.
hep-phhep-th0 citations
79
For Whom the Xenon Recoils: Magnetic Inelastic Dark Baryons
Pouya Asadi · Austin Batz · Patrick J. Fox · Samuel D. Homiller · Graham D. Kribs
We develop a theory of a dark baryon dark matter candidate that interacts with nuclei dominantly through inelastic scattering mediated by a transition magnetic dipole operator. Models are presented that can elegantly explain both the scattering rate and the size of the inelastic splitting to be consistent with the one event observed at LZ\@. Elastic scattering is suppressed due to accidental symmetries within the strongly-coupled sector. The nuclear response is dominated by a spin-dependent structure factor, thus we find a large range of masses, $1 TeV ≲ m_{χ} ≲ 50 TeV$ , and mass splitting of $100 keV ≲ δ ≲ 500 keV$ can fit the data for a variety of possible dark matter velocity distributions. The models predict that some nuclear scattering events will be accompanied by a simultaneous photon signal with energy $δ$ , which not only distinguishes this model from other inelastic dark matter explanations but also enables directional detection in conventional direct detection experiments. We briefly comment on the dark matter abundance, indirect detection signals (including the models' significantly weaker constraints from dark matter annihilation in the Sun), and the associated collider signals that arise from the meson sector of the theory.
hep-ph
80
Complex Scalar Dark Matter with a Vector-Like Quark and Lepton: Precision, Flavor, and HL-LHC
Lipika Kolay🇮🇳 · Rusa Mandal🇮🇳 · Manimala Mitra🇮🇳 · Dipankar Pradhan🇮🇳 · Subham Saha🇮🇳
We investigate a minimal extension of the SM consisting of a $Z_{3}$ -stabilized complex scalar dark matter (CSDM) candidate, a down-type vector-like quark (VLQ), and a charged vector-like lepton (VLL). The additional vector-like fermions not only enable the CSDM to reproduce the observed relic abundance beyond the Higgs-resonance region through semi-annihilation and co-annihilation processes, but also induce correlated signatures across flavor, electroweak precision, dark matter, and collider observables. We perform a comprehensive one-loop analysis of neutral meson mixing, rare meson decays, charged lepton flavor violation, anomalous magnetic moments of charged leptons, and $Z$ -pole observables. We find that neutral meson mixing and rare meson decays provide the dominant constraints on the VLQ sector, while charged lepton flavor-violating processes strongly restrict the VLL Yukawa couplings. Current direct-detection limits require Higgs-DM coupling $λ_{Φ H} ≲ 5 \times 1 0^{- 3}$ and the VLQ Yukawa coupling $y_{d} ≲ 0.05$ for TeV-scale VLQ masses, whereas present indirect-detection searches impose no additional constraints. Combining all flavor, electroweak precision, dark matter, and collider constraints, we identify viable parameter regions with CSDM masses above approximately $1.0 TeV$ and VLQ masses above about $1.5 TeV$ . We also find that the LHC can exclude VLQs (VLLs) with masses up to approximately $1.6 (0.38)$ TeV, depending on the CSDM mass, at the $2 σ$ confidence level. The HL-LHC can further probe an extended region of the parameter space, with discovery prospects at the $3 σ$ level. Finally, we demonstrate the complementarity of flavor, dark matter, and collider searches in probing this framework.
hep-ph0 citations
81
A Warped Extra Dimensional Candidate for the LZ 248 keV Event
Vincent S. H. Lee · Lisa Randall
The recent result by the LUX-ZEPLIN (LZ) experiment of a single nuclear-recoil event at $248 keV$ suggests an interpretation in terms of inelastic scattering between dark matter (DM) and the xenon target. The widely considered thermal Higgsino DM with $m_{χ} \sim$ ~TeV and mass splitting $δ \sim 350$ ~keV is essentially excluded as it would be captured efficiently by the Sun, with a resulting neutrino flux from its annihilation in excess of the IceCube limit, and expected recoils above the LZ nominal search window, where none were seen. However we argue that although these tensions apply to a Higgsino with constrained cross section, they need not apply to the broader set of inelastic candidates that alternative solutions to the hierarchy problem might suggest. We show that a new massive gauge boson, $Z^{'}$ with a candidate DM sector and Majorana mass splitting of order $\sim 1 0^{- 7}$ of the Dirac mass, evades current constraints. We propose an inelastic dark matter (iDM) candidate that can arise naturally in a Randall-Sundrum warped extra-dimensional model. The DM candidate involves a vector-like fermion confined to the TeV brane and a bulk field. The brane Lagrangian contains Dirac mass terms that are also naturally exponentially suppressed. The left-handed component of the bulk field has a Majorana mass with origin on the UV brane, while the interaction with Standard Model nucleons is mediated by a massive dark Kaluza-Klein (KK) gauge boson whose mass is also automatically in the right range. We propose a concrete model of thermal DM with $m_{χ} \sim$ ~TeV in an RS geometry with warp factor $π k R ≃ 31.7$ and the $Z^{'}$ a KK mode with natural TeV-ish scale mass in which the ratio of neutrino to quark coupling is also natural, giving a mass splitting of $δ \sim 300$ ~keV, and show how it could explain the LZ signal while being consistent with existing constraints.
hep-ph
82
Mixing-suppressed inelastic dark matter: a minimal model for the LZ 248 keV event
Seung J. Lee🇰🇷 · Taewook Youn🇺🇸
We construct a minimal Majorana singlet-vector-like-doublet model for the single nuclear-recoil-like event reported by LZ near 248 keV. At the splitting inferred from the recoil energy, an electroweak-strength $Z$ transition predicts thousands of events; singlet-doublet mixing suppresses the rate without moving the recoil spectrum. Fixed-coupling interpretations instead require a larger splitting in the extreme halo tail, but solar gravitational acceleration removes this suppression, while the larger splitting shifts recoils toward LZ's empty high-energy sideband. In our model the same mixing suppresses solar capture and annihilation, while the small mass gap required for coannihilation weakens Higgs-mediated cooling, allowing the captured population to remain extended and out of equilibrium. Imposing the relic abundance and normalizing the rate to one event leaves a two-dimensional mass-splitting parameter space. A thermalized population gives the conservative IceCube limit $δ =$ 300-301 keV; with our nonthermal cooling ansatz and elastic scattering treated at tree level, the nominal limit is $δ =$ 331-341 keV near the 730-733 GeV relic-density endpoint, which is also favored by the recoil spectrum. We outline a gauged $U (1)_{N}$ origin for the parity and splitting and a candidate $R$ -symmetric supersymmetric embedding.
hep-ph0 citations
83
AMSB in Truly Confining Gauge Theories
Riku Ishikawa🇯🇵 · Hitoshi Murayama🇺🇸 · Shota Saito🇯🇵
We study deformation of supersymmetric $t$ -confining (truly confininig) gauge theories with small anomaly mediation of supersymmetry breaking. We identify breaking pattern of global symmetries in the theories. These results can be compared in priciple to lattice simulation of non-supersymmetric theories (except for one of the cases where the theory is pseudoreal and chiral).
↳ hep-thhep-ph0 citations
84
Baryon-Accelerated Core Collapse in SIDM Halos and its Imprint on Galactic Disks
Zeineb Mezghanni🇺🇸 · Elliot Y. Davies🇺🇸 · Adriana Dropulic · Gonzalo Herrera🇺🇸 · Abdelaziz Hussein🇺🇸 · Lina Necib🇺🇸
The gravitational coupling between dark matter (DM) halos and the baryonic structures they host is one of the most powerful windows into the particle nature of DM. Self-interacting dark matter (SIDM) presents a minimal, well-motivated extension to the dark sector with dramatic consequences for the structure of galaxies and their halos. However, the impact of baryons on SIDM halo evolution and the resulting galactic structure has been underexplored in Milky Way (MW)-size galaxies. In this paper, we demonstrate that the inclusion of a baryonic component in a MW-size galaxy causes accelerated core collapse to begin within the MW's lifetime for a cross section as low as $σ / m = 1 cm^{2} / g$ . We present a suite of $N$ -body simulations of cold dark matter and SIDM MW-size galaxies with and without a baryonic component for cross sections $σ / m = [1.0, 2.5, 5.0]$ cm $^{2}$ /g. We find numerically, and semi-analytically, that the presence of a stellar disk and bulge shortens the predicted core collapse timescales from the DM only simulations by a factor of $\sim 40$ . Further, as the core collapse begins within the lifetime of the galaxy, the subsequent density increase strengthens the mid-plane restoring force exerted on stellar disk orbits, leading the disk to flare. This work quantifies both directions of the baryon--SIDM coupling: baryons accelerate core collapse in MW-sized halos, and the resulting halo evolution reshapes the disk through thinning and flaring. Both processes open new observational windows into DM.
↳ astro-ph.GAhep-ph0 citations
85
Beyond Viscosity Matching: Microscopic Relaxation in Anisotropic Flow
Olga Soloveva🇩🇪
When a gas of scattering particles is disturbed, each angular harmonic of its velocity distribution decays at its own rate. Hydrodynamics, and with it the shear viscosity, depends on only one of these rates, the one for the quadrupole harmonic. A system that scatters only a few times before it stops interacting remembers all of them. This is the situation of small collision systems such as $p + p$ , $p +$ Pb and O $+$ O, where kinetic models tuned to the same viscosity nevertheless predict different anisotropic flow. We show that this difference is not a model uncertainty but a measurement of the remaining rates: to first order in the number of collisions, ratios of flow responses equal ratios of relaxation rates, independently of the initial geometry. For the QCD collision kernel, where the rates also depend on momentum, we obtain the full spectrum of relaxation modes in closed form and show that dilute flow, viscosity, and late-time decay probe three different averages of it. A momentum-resolved kinetic solver confirms that the angular hierarchy is lost first at soft momenta and that the flow response settles at a value no single-rate model produces. The same structure governs two-dimensional electron and atomic Fermi gases.
↳ nucl-thhep-ph0 citations
86
AI in Particle Physics Education: Research Problems and Foundational Skills
M. Mikhasenko🇩🇪 · M. Stahl🇩🇪 · I. Segal🇩🇪 · D. Parmar🇩🇪 · A. Zimmer🇩🇪 · A. Kazatsky🇩🇪
Generative AI can produce perfect solutions to standard physics homework, weakening the connection between submitted work and knowledge a student can use independently. We report a redesign of the introductory nuclear and particle physics course at Ruhr University Bochum, in which AI was permitted and encouraged alongside traditional tools on unusually difficult, research-shaped assignments. We found that most students remained engaged with the assignments throughout the course and produced ambitious work, while the course did not reliably secure its foundational objective. We offer this mixed experience as a reference point for discussion.
↳ physics.ed-phhep-exhep-ph0 citations
87
Theoretical Review on Bulk Properties and Light/Strange Hadron Production in Heavy-Ion Collisions
Yuuka Kanakubo🇯🇵
Since the discovery of large elliptic flow at RHIC in the early 2000s, relativistic hydrodynamics has become a central framework for quantitative studies of the quark--gluon plasma (QGP). In parallel, increasingly sophisticated analyses have improved constraints on the initial state and the transport properties of the QGP. In this contribution, I overview the recent progress on bulk-property of QGP and light/strange hadron production.
↳ nucl-thhep-phnucl-ex0 citations
88
Self-supervised reconstruction of transients in data from space-borne gravitational-wave detectors
Yuxiang Xu🇨🇳 · Minghui Du🇨🇳 · Bo Liang🇨🇳 · Zihao Xiao🇨🇳 · Tianyu Zhao🇨🇳 · Peng Xu🇨🇳
Space-based gravitational-wave (GW) data may contain transient signals whose waveform morphologies are not known in advance. Extracting these signals is important for characterizing new sources and mitigating instrumental anomalies. However, existing deep neural network (DNN)-based extraction approaches rely on clean training targets and waveform-class-specific examples, which may limit their applicability when the transient morphology is not specified in advance. This work develops a Noise2Noise (N2N)-inspired self-supervised framework that learns from noisy observations without clean training targets and requires no transient-specific waveform templates at inference. A single model trained on noisy massive black-hole binary (MBHB) observations provides high-overlap MBHB recovery and recovers the dominant morphologies of instrumental glitches and other GW transient signals such as cosmic string bursts in source-confused test data. Beyond waveform recovery, when independent information identifies a candidate transient as instrumental, its extracted waveform can be subtracted from the data without an anomaly-specific template. In a simulated continuous data stream, this procedure substantially suppresses the injected-anomaly power within the glitch-dominated frequency band. These results support the use of self-supervised extraction for initial waveform estimation of candidate transients with unknown morphologies, enabling subsequent characterization and, where appropriate, conditional subtraction of instrumental anomalies.
↳ gr-qcastro-ph.GAastro-ph.IMhep-ph0 citations
89
Quantum Theory Angular Momentum; Electronic version 2026
Niels R. Walet
This is an electronic version of the open source book "Quantum Theory of Angular Momentum" by D. A. Varshalovich, A. N. Moskalev, V. K. Khersonskii, original copyright o̧pyright} 1988 by World Scientific Publishing Co. Pte. Ltd, with the CC-BY 4.0 open source ebook funded by SCOAP. We have made appropriate modifications for the modern age--such as python-based symbolic manipulators to replace algebraic and numeric the tables. The new version contains a number of small modification, even though it is close to the original, with additional indices, hyperlinking, redrawing of figures. There has been a substantial check of the results presented, supported by the use of AI, even though all mistakes are the author's responsibility. All material is available from the book's github site (https://github.com/nwalet/Varshalovich/), where new updated versions will also be presented.
↳ nucl-thhep-ph0 citations
90
The Wilson-line-dressed charged sector of scalar QED: superselection and the infraparticle
Gordon W. Semenoff🇨🇦 · Conor Waterfield🇨🇦
We develop a manifestly gauge and Lorentz invariant perturbative calculus to study the finite time and distance evolution of the electrically charged states created by Wilson-line-dressed scalar field operators in scalar quantum electrodynamics. By an Osterwalder-Schrader reflection and Euclidean gluing, the overlap of two dressed states is expressed as a Euclidean 2 point function of dressed operators, which is then evaluated in renormalized perturbation theory with a Stueckelberg photon mass as a gauge, BRST and Lorentz invariant infrared cutoff. This renders explicit and computable in closed form several structural features of the charged sector that have so far been accessible mainly through non-perturbative or algebraic arguments. We find that states dressed by non-parallel Wilson lines are ``cloud orthogonal". Their overlap vanishes as a power of the infrared regulator, with an exponent that depends only on the angle between the two dressings and is an infrared analogue of the cusp anomalous dimension with the difference that it is one-loop exact whenever the charged matter is mass-gapped. Charged states are thereby superselected by the orientation of their dressing. Within a superselection sector the 2 point function is infrared finite but exhibits the infraparticle. The mass shell pole is replaced by the edge of a branch cut. As a result, the asymptotic spread of a dressed charge is a power law in proper time with a one-loop-exact computable exponent depending on the dressing and on the direction of motion. We show that although cloud orthogonality and the infraparticle are each extremely sensitive to fundamental infrared cutoffs, the infraparticle scaling law persists across a wide window of proper time.
↳ hep-thhep-phquant-ph0 citations
91
Microscopic study of baryon stopping in low-energy heavy-ion collisions within UrQMD model
Sudhir Pandurang Rode🇷🇺
In low-energy heavy-ion collisions, baryon stopping is an important process, in which protons from the initial colliding nuclei are stopped at mid-rapidity region. Quantifying such stopping can reveal information on the properties of the nuclear medium, such as net-baryon density. Though experimental measurement of net-proton rapidity spectra provides constraints, microscopic origin of such protons is not fully accessible. Transport model studies can therefore provide deeper insight into the microscopic origin of protons transported from initial nuclei, complementing experimental measurements. This article presents an investigation of baryon stopping in minimum-bias Au+Au collisions over a wide range of beam energies, $s_{N N} = 2.4 - 17.3$ GeV ( $E_{lab} = 1.23 A - 158 A$ GeV). Final-state protons are classified based on their origin by analyzing their interaction history in the UrQMD model. A significant fraction of transported protons at mid-rapidity originates from initial neutrons rather than initial protons, referred to as \textit{isospin-converted} protons, and their contribution as a function of collision energy and centrality is quantified. Anisotropic flow coefficients of different proton categories are estimated and compared with experimental measurements. Furthermore, a comparison between the $π^{-} / π^{+}$ ratio and \textit{isospin conversion} rate is performed. The latter is further compared with the $α$ parameters of the Kitazawa-Asakawa formalism, revealing a significant deviation from the chemical equilibrium assumption $α_{N} = α_{π}$ below $s_{N N} ≲$ 10~GeV. Finally, the saturation of the isospin conversion rate is found to coincide with the onset of nuclear transparency, demonstrating that isospin randomization and baryon stopping are coupled phenomena in hadronic transport across the NICA/FAIR energy range.
↳ nucl-thhep-exhep-phnucl-ex0 citations
92
Effective Field Theory of Protonium
Hans-Werner Hammer🇩🇪 · Akaki Rusetsky🇩🇪
We investigate the level shifts in protonium using the framework of non-relativistic effective field theory (NREFT). Our study is prompted by the PUMA collaboration's plans to probe the neutron-to-proton ratio in the nuclear density tail using antiprotonic atoms -- a method for which light atoms provide an important benchmark. We calculate the corrections to the Deser-Goldberger-Baumann-Thirring formula for the complex level shift of S-wave states from the unitary cusp and Coulomb photon exchange. Structure dependent corrections enter at the next order. For higher-partial-wave states, they enter already at leading order. Using input from chiral NNbar interactions, we compare to other calculations and measurements from LEAR.
↳ nucl-thhep-ph0 citations
93
Ultra-slow-roll Inflation with Non-perturbative Non-Gaussianity and Scalar Induced Gravitational Waves
Manuel Drees🇩🇪 · Chenhuan Wang🇩🇪
An ultra-slow-roll phase during inflation could potentially produce the right abundance of primordial black holes (PBHs) for them to form all of dark matter (DM). We consider such a scenario, carefully treating the transitions from slow to ultra slow roll inflation and back, using a parametrisation of the inflaton potential that can describe inflation from the time when CMB scales crossed out of the horizon until its end. A $δ N$ analysis shows that this model can possess $O (1)$ non-Gaussianity. When computing the primordial black hole abundance, we keep the full non-linear relation between curvature perturbations and the density contrast and consider the non-Gaussianity to all orders. We find that $O (1)$ non-Gaussianity is sufficient to enhance the PBH abundance by orders of magnitude, leading to reduced gravitational wave (GW) signals for fixed PBH abundance. The signal to noise ratio is computed for future gravitational wave observatories. We find that, in spite of the reduced strength, the GW signal is well above the sensitivity of LISA if PBHs form a significant component of DM.
↳ astro-ph.COhep-ph0 citations
94
Spontaneous counterflow in rotating supersolids
Silvia Trabucco🇮🇹 · Elena Poli🇮🇹 · Massimo Mannarelli🇮🇹 · Francesca Ferlaino🇦🇹
Rotating supersolids challenge the conventional notion of superfluid flow: quantized vortices coexist with crystalline order arising from the system's intrinsic density modulation. Drawing on concepts developed in the context of superfluid helium, this seemingly paradoxical state is often described phenomenologically in terms of a dual response, combining superfluid flow with rigid-body-like motion. Here we show that these apparently distinct behaviors emerge from a single microscopic velocity field, globally constrained by irrotationality. By applying a Helmholtz decomposition, we disentangle a divergence-free incompressible component, which carries vortex circulation, from a curl-free compressible component generated by the intrinsic density modulation. In absence of vortices, the response is entirely encoded in the compressible field: the droplets co-rotate with the external drive, while the interstitial fluid develops an oppositely directed counterflow that preserves vanishing circulation. Above the vortex nucleation threshold, the incompressible component carries the usual quantized circulation, whereas the compressible field counteracts the vortex-induced angular momentum, reducing the total jump with respect to an unmodulated condensate. Our results recast supersolid rotation in terms of a flow-counterflow response, providing a microscopic interpretation of the phenomenological rigid/superfluid partitioning.
↳ cond-mat.quant-gashep-ph0 citations
95
A phenomenological approach to direct $K^{*}$ production and hadronic medium effects in nucleus-nucleus collisions at high baryon density
Hongcan Li🇨🇳 · Yun Liu🇨🇳 · Guangyu Zheng🇨🇳 · Yaping Wang🇨🇳 · Guannan Xie🇨🇳 · Gao-chan Yong🇨🇳
Short-lived hadron resonances serve as sensitive probes of the late-stage hadronic medium in heavy-ion collisions. Using the AMPT-HC model, we study $K^{*} (892)$ production and its hadronic medium effects in Au+Au collisions at $s_{NN} = 3$ GeV, a region of high baryon density. We introduce a phenomenological direct-production mechanism for $K^{*}$ by replacing a fraction of the final-state kaons produced in the $NN \to NYK$ and $MN \to YK$ channels with $K^{*}$ resonances, with the substitution fraction controlled by a parameter $α$ while conserving four-momentum. The direct $K^{*}$ is produced early, at about 6 fm/ $c$ , with little centrality dependence, whereas resonance fusion via $K + π \to K^{*}$ occurs later, with the mean production time increasing from about 8 to 10 fm/ $c$ toward central collisions. Consequently, direct $K^{*}$ mesons suffer stronger daughter rescattering, leading to a pronounced decrease in reconstruction efficiency toward central collisions, while the $K^{*}$ survival rate remains close to unity. Elastic scattering of the daughters also shifts the invariant mass away from the resonance peak, contributing to the background-like component. The $K^{*} / K$ centrality dependence reflects the competition between direct production and resonance fusion and is sensitive to $α$ . At 3 GeV, a moderate direct-production contribution may result in an increasing $K^{*} / K$ ratio toward central collisions, providing a testable prediction for future measurements.
↳ nucl-thhep-ph0 citations
96
An EOS-Driven Extension of NSCool for Compact Star Cooling with Hadronic and Quark Degrees of Freedom
Federico Nola🇮🇹 · Fernando Arias-Aragón🇪🇸
We present an EOS-driven extension of the NSCool thermal evolution code that enables complete tabulated equations of state to be treated within a single composition-based input structure. The generalized NEW interface includes additional baryonic fractions, a bosonic composition variable, the hadronic volume fraction, and quark fractions, allowing nucleonic, hyperonic, resonant-baryonic and hybrid hadron-quark configurations to be handled within the same workflow. The neutrino sector is extended accordingly, including updated nucleonic modified Urca and bremsstrahlung rates, additional baryonic direct Urca channels, hyperonic processes, baryonic pair breaking and formation and quark direct Urca, modified Urca, bremsstrahlung and PBF contributions. In mixed phases, emissivities and the corresponding core heat capacity contributions are evaluated from phase-local quantities and combined using the hadronic volume fraction. The implementation is validated against the original NSCool calculation for a controlled nucleonic benchmark and demonstrated with representative hadronic and quark-containing EOSs. These calculations are intended as software validation tests of the generalized workflow rather than as observational fits or statistical EOS inference.
↳ nucl-thastro-ph.HEhep-ph0 citations
97
Scalar field with nonminimal couplings to metric-affine geometry
Ilaria Andrei🇪🇪 · Damianos Iosifidis🇮🇹 · Laur Järv🇪🇪 · Margus Saal🇪🇪
We study a scalar field nonminimally coupled to metric-affine gravity within actions linear in the affine curvature and containing all independent parity-even and parity-odd terms quadratic in torsion and nonmetricity, including mixed contractions. We also include Nieh-Yan-like derivative couplings between the scalar-field derivative and the four torsion and nonmetricity vectors. We derive the connection, metric, and scalar-field equations and, since the connection equation is algebraic, eliminate the independent connection on the generic nondegenerate branch to obtain an equivalent metric scalar-tensor theory in which the non-Riemannian interactions are encoded in an effective kinetic function. We classify several sectors and find that the pure quadratic nonmetricity and pure quadratic torsion sectors separately leave the Einstein-frame kinetic function unchanged relative to the simplest metric-affine scalar-tensor model, whereas their simultaneous presence, the derivative couplings, and generic mixed torsion-nonmetricity interactions can modify it. In the derivative-coupling sector, projective consistency imposes a relation among the couplings. We then consider polynomial coupling functions and study the resulting canonical field redefinition and Einstein-frame potentials. In particular, we illustrate how derivative and mixed torsion--nonmetricity couplings reshape quadratic and quartic potentials in canonical-field space, and show that a quadratic Jordan-frame potential can be mapped, for a suitable choice of derivative and nonminimal couplings, into a natural-inflation potential after canonical normalization. Finally, we separately impose the cosmological principle, determine the reduced combinations of quadratic couplings and the scalar field hypermomentum, and obtain the corresponding modified cosmological equations in the simplest sectors.
↳ gr-qchep-phhep-th0 citations
98
Analyzing momentum distributions in light nuclei with the operator product expansion
Jiexin Yu🇨🇳 · Bingwei Long🇨🇳
We analyze the high-momentum tails of nucleon distributions in nuclei using the operator product expansion (OPE) and Pionless effective field theory. The OPE factorizes the distributions into Wilson coefficients, determined from two-nucleon scattering, and local-operator matrix elements (LOMEs). Because the leading $^{1} S_{0}$ and $^{3} S_{1}$ Wilson coefficients are nearly degenerate in the single-nucleon distribution, we construct the OPE of the two-nucleon momentum distribution, which separates the two contributions into distinct spin-isospin channels. From variational Monte Carlo two-nucleon distributions of \isotope[3]{He}, \isotope[4]{He}, \isotope[6]{Li}, and \isotope[12]{C}, we extract the LOMEs and accurately reconstruct the single-nucleon distributions at large momenta. In potentials without explicit non-nucleon degrees of freedom such as AV18, the Wilson coefficients of the single- and two-nucleon OPEs are proportional, yielding approximate relations between the two distributions.
↳ nucl-thhep-ph0 citations
99
Finding the distribution of matter using lenses - I: deconvolution-based reconstruction with CMB lensing
Ajoy Dawn · Jun-Qian Jiang🇨🇳 · Dhiraj Kumar Hazra🇮🇳 · Benjamin L'Huillier · Arman Shafieloo🇰🇷
The matter power spectrum is one of the primary statistical descriptors of the large-scale distribution of matter in the Universe and provides a powerful probe of cosmic structure formation. Measurements of cosmic microwave background (CMB) lensing offer an integrated view of the matter distribution over a wide range of redshifts, enabling the reconstruction of the underlying matter power spectrum. In this work, we reconstruct the reference linear matter power spectrum $P_{lin} (k, 0)$ from the baseline joint CMB lensing measurements of Planck PR4, ACT DR6, and SPT-3G using a covariance-weighted modified Richardson-Lucy(MRL) deconvolution algorithm. The reconstructed spectrum is found to be consistent with the fiducial linear prediction on large scales, while exhibiting a systematic enhancement for $k ≳ 0.1 Mpc^{- 1}$ , where nonlinear gravitational evolution becomes important. To investigate this behavior, we introduce a scale-dependent correction factor, $A (k)$ , defined through $P (k) = A (k) P_{nl} (k),$ where $P_{nl} (k)$ is the fiducial nonlinear matter power spectrum obtained from 2LPT simulations. The reconstructed correction factor remains consistent with unity within $2 σ$ confidence over the reconstructed range, indicating that the observed enhancement is well explained by the standard nonlinear evolution of the matter power spectrum. In addition, the reconstruction shows agreement with the fiducial BAO template around the BAO feature at $k \sim (0.04 - 0.06) Mpc^{- 1}$ , indicating that some BAO-scale information survives the lensing projection.
↳ astro-ph.COhep-phphysics.data-an0 citations
100
Finding the distribution of matter using lenses - II: deconvolution-based reconstruction with 3x2pt measurements
Jun-Qian Jiang🇨🇳 · Ajoy Dawn · Dhiraj Kumar Hazra🇮🇳 · Benjamin L'Huillier · Arman Shafieloo🇰🇷
We present a deconvolution-based framework for testing scale-dependent departures of the late-time matter power spectrum from a fiducial cosmological model using $3 \times 2$ pt measurements. We introduce a free-form scale-dependent modulation $A (k)$ of the fiducial nonlinear matter power spectrum and construct the linear response of binned galaxy-clustering, galaxy-galaxy-lensing, and cosmic-shear spectra to the discretized modulation $A (k)$ . The response is evaluated with full-sky, beyond-Limber kernels including density, redshift-space-distortion, gravitational-shear, and intrinsic-alignment contributions. We reconstruct $A (k)$ using a regularized modified Richardson-Lucy algorithm, with weak diffusion in $ln k$ and selection of the minimum- $χ^{2}$ solution along the iteration history. Using Rubin/LSST Year 10-like synthetic data, we find that oscillatory modulations with amplitudes $≳ 1%$ can be recovered over $0.1 ≲ k ≲ 0.5 Mpc^{- 1}$ , provided the oscillation frequency $f ≲ 10$ on $lo g_{10} [k / (0.2 Mpc^{- 1})]$ . We further introduce a posterior-weighted consistency statistic calibrated with posterior-predictive null mocks, thereby accounting for cosmological and nuisance-parameter uncertainties without relying on Wilks' theorem. The null case is consistent with $A (k) = 1$ , while a $1%$ oscillatory modulation is detected at $\sim 2.6 σ$ . These results demonstrate the potential of regularized deconvolution as a model-independent consistency test of the matter power spectrum in future $3 \times 2$ pt surveys.
↳ astro-ph.COhep-phphysics.data-an0 citations
101
Vacuum Decay and Baryogenesis Associated with Primordial Black Holes at Finite Temperature
Qi Sun🇨🇳 · Ligong Bian🇨🇳
Within finite-temperature effective potential framework, we study the effects of PBHs on vacuum decay, the associated gravitational wave spectrum, and the baryon asymmetry. For the PBHs considered, the Hawking temperatures are below the ambient temperature, and their dominant effect is taken to be the gravitational distortion of the Higgs field configuration. Relative to flat spacetime, the PBH background reduces the vacuum decay exponent, enhances the gravitational wave peak amplitude, and shifts the peak frequency downward. For PBH masses of roughly $1 0^{11} g - 1 0^{13} g$ , the sphaleron energy is reduced, while the small PBH abundance renders the associated washout negligible. Additionally, over roughly the same mass range, PBH-emitted BSM particle decays generate a baryon asymmetry too small to spoil the agreement between the baryon abundances inferred from BBN and CMB.
↳ astro-ph.COhep-ph0 citations
102
Kinematic Control and Dephasing Dynamics of Quantum Resources in $e^{+} e^{-} \to τ^{+} τ^{-}$
Elhabib Jaloum🇲🇦 · Omar Bachain · Mohamed Amazioug🇲🇦 · Rachid Ahl Laamara🇲🇦
We characterize several quantum resources carried by the spins of the $τ^{+} τ^{-}$ pair produced in $e^{+} e^{-}$ annihilation. At the Belle-II energy, $s = 10.579 GeV$ , Bell nonlocality, steerability, entanglement of formation, and coherence are governed by the production angle and are largest for transverse emission, $ϑ = π /2$ . Their common kinematic origin is exposed by expressing the spin state as a velocity and angle-dependent mixture of a separable contribution and a maximally entangled component. Within the physical production domain, this representation connects the weakly correlated threshold state at $s = 2 m_{τ}$ to the Bell-state limit approached at ultrarelativistic energies. We then propagate the two-spin state through a phenomenological correlated-dephasing channel to determine how environmental memory and inter-channel classical correlations affect the available resources. Memory effects generate collapses and revivals that are absent from the monotonic Markovian evolution. The analysis therefore separates the kinematic mechanism that creates the spin correlations from the noise properties that control their subsequent survival.
↳ quant-phhep-exhep-phhep-th0 citations
103
The Interplay of Symmetry Energy Uncertainties, Nonlinear $σ - δ$ Coupling, and Dark Matter in Neutron Star Macroscopic Properties
Zhaohui Feng · Xiaoxuan Zhai🇨🇳 · Shuangxuan Chen🇨🇳 · Defu Hou🇨🇳
The poorly constrained density dependence of the nuclear symmetry energy introduces significant uncertainties in the equation of state (EOS) of dense nuclear matter and, consequently, in neutron-star properties. We systematically investigate how uncertainties in the symmetry energy $E_{sym}$ and its slope $L$ at saturation density $n_{0}$ affect NS properties within the relativistic mean-field (RMF) framework, including the effects of nonlinear $σ$ - $δ$ coupling and possible admixture of dark matter(DM) . For fixed $E_{sym} (n_{0})$ and $L (n_{0})$ , we find that the $σ$ - $δ$ coupling with $g_{σ δ} = - 0.004$ induces an abnormal softening of the EOS, which simultaneously increasing the maximum NS mass and reducing the stellar radius and tidal deformability. A similar behavior is found in the presence of DM with Fermi momentum $k_{F}^{DM} = 50 MeV$ at $E_{sym} (n_{0}) = 36 MeV$ . In this case, the RMF EOS satisfies the tidal-deformability constraint from GW170817. We further find that the surface curvature of NSs is strongly correlated with the stiffness of $E_{sym}$ , with softer symmetry energy corresponding to larger surface curvature. Our results also indicate that the behavior of $E_{sym}$ around $n_{0}$ is mainly governed by isoscalar rather than isovector parameters.
↳ nucl-thhep-ph0 citations
104
A Two-Parameter Framework for the Diffuse Supernova Neutrino Background
Cecilia Lunardini🇺🇸 · Xingyun Yang🇨🇳
Following important experimental developments, tests of the Diffuse Supernova Neutrino Background (DSNB) are entering a new phase that might lead to a discovery. This motivates the development of simple and broadly applicable tools for comparing theoretical predictions and interpreting experimental results. We show that, over the energy range relevant to current detectors, the DSNB is well described by an exponential spectrum, characterized by the differential flux at 20 MeV, $ϕ_{20}$ , and a spectral energy scale, $E_{0}$ . We fit the spectra of 24 representative models and demonstrate that the exponential description provides an excellent approximation. We then recast the recent Super-Kamiokande results in the $(ϕ_{20}, E_{0})$ plane, showing that model-specific best fits and upper bounds can be interpreted naturally within this framework. Our results indicate that, above realistic detection thresholds, and until the precision phase is reached, the observable DSNB is effectively a two-parameter phenomenon. We advocate that the $(ϕ_{20}, E_{0})$ parameterization be adopted as a standard, to be used routinely to report future theoretical predictions and experimental results.
↳ astro-ph.HEhep-phnucl-th0 citations
105
How strange: Phase diagrams with 3 critical points
Mateus Reinke Pelicer🇺🇸 · Nikolas Cruz Camacho🇺🇸 · Rajesh Kumar · Veronica Dexheimer🇺🇸 · Jacquelyn Noronha-Hostler🇺🇸
We show that the Chiral Mean-Field model (CMF) can produce a phase diagram with three critical points: the nuclear liquid-gas transition, quark deconfinement, and a strangeness driven transition. The strangeness driven transition separates a mainly nucleonic phase from one dominated by hyperons and baryon resonances. We discuss the compositional change in these transitions and their possible signatures in heavy-ion collisions and neutron star mergers.
↳ nucl-thastro-ph.HEhep-ph0 citations
106
Small-Scale Clustering of Primordial Black Holes: The Little Red Dot Mass Function and the High-Redshift Galaxy Tension
Borui Zhang · Wei-Xiang Feng🇨🇳 · Haipeng An🇨🇳
Supermassive black holes (SMBHs) in "little red dots" (LRDs) discovered the James Webb Space Telescope (JWST) may result from runaway mergers of primordial black holes (PBHs) in clusters---through long--short mode coupling on small scales in the early Universe. In this framework, we derive the SMBH mass function, together with the compactness and overmassive features of LRDs. We also estimate that the dense gas residing in PBH clusters is consistent with LRD observations. In addition, SMBHs formed from PBH clusters can help accelerate galaxy formation at high redshifts, thus alleviating tension with $Λ$ CDM cosmology.
↳ astro-ph.GAastro-ph.COgr-qchep-ph0 citations
107
Hydrodynamic attractors
Tilman Enss · Michal P. Heller🇧🇪 · Alexandre Serantes🇧🇪 · Clemens Werthmann🇧🇪
Attractors are effective low-dimensional structures, defined in a chosen set of observables, that trajectories from different initial states approach; hydrodynamic attractors are those on which the late-time evolution is governed by hydrodynamic constitutive relations. Motivated by nuclear collisions and ultracold atomic gases, this chapter distinguishes attractorization (the loss of sensitivity to some directions in the space of initial states) from hydrodynamization (the onset of validity of hydrodynamic constitutive relations). Using mainly conformal, boost-invariant Bjorken flow, we compare Müller-Israel-Stewart-type theories, kinetic theory, holography, and classical Yang-Mills fields. Forward attraction, produced by the decay of non-hydrodynamic modes, is distinguished from pullback attraction, which can select a unique regular solution, and from expansion-driven attraction, which can suppress initial-state sensitivity before microscopic relaxation, with or without a subsequent fluid regime. Divergent gradient expansions and their transseries completions, the state-space picture, and adiabatic hydrodynamization provide complementary descriptions. Applications to nuclear collisions include particle production, transverse energy and flow, the initialization of and linear response around attracting backgrounds, jet quenching, and attractor-informed modifications of hydrodynamic models. For ultracold Fermi gases, we review theoretical proposals for bulk-channel attractors under scattering-length drives and distinguish them from recent measurements of short-time contact and momentum-distribution dynamics.
↳ nucl-thcond-mat.quant-gashep-phhep-th0 citations

Affiliations

first authorsco-authorsvia INSPIRE