HEP Phenomenology·hep-ph

Wed·Sep 2, 2026Wednesday·September 2, 2026

48 papers—39 primary·9 cross-listed

01
Reining in an Agentic Harness for High Energy Physics
Tony Menzo🇺🇸 · George T. Fleming🇺🇸 · Konstantin T. Matchev🇺🇸 · Stephen Mrenna🇺🇸 · Alexander Roman🇺🇸
Agentic systems now address tasks across theoretical, phenomenological, and experimental high energy physics (HEP), but their scientific capabilities remain difficult to reuse across different large language models, providers, and harnesses. We argue that stable parts of these workflows should be promoted into versioned scientific operations and exposed through common protocols. Existing general-purpose harnesses can then be specialized for HEP through task-specific sets of tools and skills, while community-maintained registries would make these capabilities discoverable and citable. We identify mismatches in conventions, assumptions, and domains of validity among independently developed operations as a potential obstacle to their composition, and discuss machine-readable scientific contracts as one possible solution. These design principles and evaluation guidelines provide a near-term path toward a portable and community-maintained agentic harness for HEP.
hep-phhep-exhep-th0 citations
02
Solar Spin-Dependent Dark Matter-Neutron Cross Section Constraints: The Lost Case
Thong T.Q. Nguyen🇸🇪 · Carlos Blanco🇺🇸 · Tim Linden🇸🇪
The Sun has long served as a natural dark matter detector, capturing halo particles that scatter with solar nuclei and electrons and subsequently produce indirect signals from dark matter annihilation that can be probed by either neutrino or $γ$ -ray instruments. Previous efforts have computed cross-section constraints for dark matter scattering with electrons, as well as spin-independent and spin-dependent dark matter-proton scattering. However, the spin-dependent dark matter-neutron scattering scenario has been neglected, despite its importance in direct detection. For the first time, we compute the capture and evaporation rates for spin-dependent dark matter-neutron scattering in the Sun, including odd-neutron isotope targets in the current standard solar model. Comparing the predicted annihilation signals against current neutrino and $γ$ -ray observations, and projecting the reach of upcoming detectors, we find that solar constraints exceed direct detection limits for several annihilation channels. For models in which the dark matter annihilates into long-lived mediators, these constraints can extend below the neutrino fog.
hep-phastro-ph.HEastro-ph.SR2 citations
03
Neutrino Electroweak Couplings and the Neutrino Fog at Belle II
Carlos Henrique de Lima🇨🇦 · David McKeen🇨🇦 · Afif Omar🇨🇦 · Douglas Tuckler🇨🇦
The mono-photon process $e^{+} e^{-} \to γ + invisible$ at Belle II probes both invisible new states and the electroweak couplings of neutrinos. In this work, we study the process $e^{+} e^{-} \to γ ν ν ˉ$ , finding that Belle II with the full expected dataset can determine the neutrino-sensitive effective weak mixing angle to a 3.6 $%$ relative statistical precision, competitive with existing neutrino probes at other energy scales. Polarized beams, as proposed for the Chiral Belle upgrade, separate the neutral- and charged-current contributions and provide independent access to each, giving a handle on the chiral structure of the neutrino gauge interactions. The same process is an irreducible background to dark boson searches, producing a neutrino fog once the luminosity exceeds 1 ab $^{- 1}$ .
hep-phhep-ex0 citations
04
Searching for Axions on a Higher Note: Third-Harmonic Generation from Colliding High-Intensity Laser Beams
Ashis Paul🇺🇸 · Leone di Mauro Villari · Davide Tedeschi🇺🇸 · Carino Ferrante · Luca Di Luzio🇮🇹 · Andrea Marini
We propose a new laboratory strategy to generate and detect axion-like particles via third-harmonic generation induced by two non-collinear, polarised high-intensity laser beams of peak intensity of the order of $1 0^{24} W/c m^{2}$ , where the third-harmonic signal is generated by the axion field. Starting from the axion-modified Maxwell equations, we analytically derive the axion-induced third-harmonic field, and show that by using state-of-the-art petawatt laser facilities, a detectable signal can be obtained over a broad range of axion masses and couplings. A key feature of the setup is that the axion-photon conversion rate can be resonantly enhanced by tuning the angle between the two beams through a mechanism that does not depend on the physical volume of the apparatus. The proposed configuration may therefore probe an unexplored region of axion parameter space and pave the way for next-generation high-power laser-based axion searches.
hep-phhep-exphysics.optics0 citations
05
The recasting bound atlas on pair production of vector-like quarks
Thomas Flacke🇰🇷 · Manuel Kunkel🇩🇪
We present a comprehensive recasting study of pair production of vector-like quarks. We consider decays of vector-like quarks into third generation quarks and Standard Model bosons or exotic top-philic scalars. We derive recasting bounds on all 43 combinations of decay channels. Using the efficiencies of each channel, we obtain combined limits across decay channels by adding up the contributions to each signal region. A data base of recasting results along with example codes is published, allowing for application to different models without the need for rerunning recasting tools. We demonstrate the utility of the data base by setting bounds on several sample models.
hep-phhep-ex0 citations
06
Dynamics and Frequency Conversion of Accreting Axion Clouds
Ximeng Li🇨🇳 · Zhen Zhong🇮🇹 · Yifan Chen🇨🇳 · Yue Zhao🇨🇳 · Hidetoshi Omiya🇯🇵 · Vitor Cardoso🇩🇰
Axion fields can form exponentially growing gravitational clouds around compact objects through self-interaction-driven relaxation of ambient axion waves. As the field amplitude approaches the axion decay constant, nonlinear effects become important. We identify two distinct regimes of late-time evolution, determined by the gravitational fine-structure constant and the cloud growth rate: a Bosenova regime, characterized by collapse accompanied by explosive axion bursts, and a saturation regime, in which self-interaction-induced axion emission balances accretion. In the latter regime, the emitted axion radiation exhibits stable discrete spectral lines at odd multiples of the bound-state energy, directly probing the global structure of the axion potential beyond its quadratic minimum. We show that single-cosine potentials and QCD axion-like potentials predict distinct emission spectra, enabling probes of the underlying axion self-interaction structure and its ultraviolet completion through terrestrial detection of relativistic axion fluxes from compact objects.
hep-phastro-ph.HEgr-qchep-ex+10 citations
07
Anomaly detection for multijet scenarios
Gregor Kasieczka🇩🇪 · Sung Hak Lim🇰🇷 · Louis Moureaux🇩🇪 · Tore von Schwartz🇩🇪 · David Shih🇺🇸 · Chitrakshee Yede🇩🇪
Signals of physics beyond the Standard Model continue to resist discovery at the LHC. Recent years have seen the proliferation of new anomaly detection techniques, promising discovery with significantly fewer model assumptions than traditional approaches. Strategies based on weak supervision have been especially successful, but so far were largely limited in scope by their reliance on a resonance manifesting a decay into a pair of jets. In this work, we demonstrate that a well-established idea from jet substructure physics - recursive soft drop - in combination with the CATHODE technique for anomaly detection can be used to simultaneously perform anomaly detection for signals with an arbitrary number of jets in the final state, greatly increasing the scope of such searches.
hep-phhep-exphysics.data-an0 citations
08
Magnetic field-induced enhancement and quenching of Urca emission in quark matter
William Gyory🇺🇸 · Igor A. Shovkovy🇺🇸
Using first-principles field-theoretic methods, we investigate neutrino emission from strongly magnetized dense quark matter under conditions relevant to compact stars. We account for Landau-level quantization of both electron and quark states and show that it strongly modifies the kinematics of Urca processes. In particular, quark quantization restricts the available phase space in which both quark and electron energies can simultaneously lie near their respective Fermi surfaces. At moderately strong magnetic fields, before pronounced quark quantization sets in, the emission rate tends to increase on average with increasing field strength. In the regime of very strong fields, however, the increasingly restricted phase space first gives rise to Shubnikov--de Haas-type oscillations and then to resonance-like spikes near a discrete sequence of Urca-resonant magnetic field values, separated by regions of strong suppression. Finally, the emission rate becomes nearly completely quenched once $∣ e B ∣ ≳ 6 μ_{e} μ_{u}$ , corresponding to approximately $B ≳ 1.5 \times 1 0^{19} \mbox G$ for the representative set of model parameters considered. We also find significant anisotropy in the longitudinal momentum emission near the Urca-resonant magnetic field values.
hep-phastro-ph.HEnucl-th0 citations
09
Radiative Corrections and Reheating in Supergravity Models of Inflation
John Ellis🇬🇧 · Tony Gherghetta🇺🇸 · Kunio Kaneta🇯🇵 · Wenqi Ke🇺🇸 · Keith A. Olive🇺🇸
We consider the effects of radiative corrections in Starobinsky-like models of inflation, concentrating on models of inflation formulated in N=1 no-scale supergravity. Inflaton couplings to matter fields are necessary for reheating and these have an impact on loop corrections to the inflaton potential. Whilst corrections due to the supergravity couplings of the inflaton to Standard Model (MSSM) fields are negligible, we use {\it Planck} data to obtain interesting constraints on GUT bilinear couplings, vevs, and gauge boson masses that could be sharpened by future CMB measurements.
hep-phastro-ph.COhep-th0 citations
10
Two-Stage Machine Learning Strategy for Scalar and Vector Leptoquark Discrimination at the LHC
Ernesto Arganda🇪🇸 · Martín de los Rios🇦🇷 · Andres D. Perez🇪🇸 · Rosa M. Sandá Seoane🇪🇸 · Alejandro Szynkman🇦🇷
We present a machine learning framework for the characterization of leptoquark (LQ) signals at the Large Hadron Collider, focusing on the discrimination between scalar (SLQ) and vector (VLQ) hypotheses. The method is based on a two-stage inference pipeline that combines a classifier trained to separate Standard Model backgrounds from a mixed LQ signal with a second classifier designed to distinguish between SLQ and VLQ scenarios, using the signal yield inferred from the first-stage classifier to guide the corresponding scalar and vector mass hypotheses. A test statistic is constructed from the classifier outputs and interpreted using reference probability density functions. The approach is applied to realistic LHC final states with hadronically decaying tau leptons, multiple jets, and missing transverse momentum, and its performance is assessed using simulated pseudo-experiments. We show that the proposed strategy provides a robust and statistically consistent procedure to discriminate between SLQ and VLQ signals across a wide range of masses and signal stregths. We find that the spin identification power closely follows the discovery potential, demonstrating that determining the spin nature of a newly discovered LQ does not require substantially larger datasets than those needed for discovery itself.
hep-phhep-ex0 citations
11
Spin density matrix for high-spin particles
Shaogang Peng🇨🇳 · Xin Chen🇨🇳 · Yuxuan Zhang🇨🇳 · Qi Cai🇨🇳 · Naiwen Xing🇨🇳 · Yue Xuy
The spin density matrix (SDM) characterizes the spin state of a particle, which provides important information for understanding its production mechanism. A general discussion of the SDM under parity conservation, and specific SDM parameterizations for spin-1 and spin-2 particles are provided, which respect all the expected constraints. The imaginary (real) part of SDM is related to the degree of odd-rank (even-rank) polarization, with specific expressions given for spin-1 and spin-2 cases. Examples of applications of the SDM to angular analyses of several decay processes with different spin-parity hypotheses are also provided, which could be helpful in experimental data analyses.
hep-ph0 citations
12
Photon Gas Thermodynamics with $κ$ -generalized statistics at Planck-Scale
Xinyi Yang🇨🇳 · Qi Xiong🇨🇳 · Guifeng Su🇨🇳 · Yi Zhang🇨🇳
Kaniadakis, or $κ$ -generalized, statistical mechanics provides a flexible framework for describing complex systems in the relativistic regime and predicts a richer phenomenology compared to its standard Maxwell-Boltzmann counterpart. In the present work, we extend the investigation of photon gas thermodynamics at the Planck scale within doubly special relativity to the framework of $κ$ -generalized statistical mechanics. By adopting the $κ$ -generalized statistical approach, we derive the principal thermodynamic quantities of a photon gas at the Planck scale, including the internal energy $U$ , Helmholtz free energy $F$ , pressure $P$ , entropy $S$ , and heat capacity $C_{V}$ . We find that these $κ$ -deformed thermodynamic quantities exhibit nontrivial dependence on the deformation parameter $κ$ . We then numerically evaluate these quantities as functions of temperature $T$ , and reveal that, as $T$ approaches the Planck scale, the $κ$ -deformed thermodynamic quantities are significantly suppressed relative to those in special relativity, while in the low-temperature regime they are enhanced and exceed their counterparts in special relativity, as a consequence of the $κ$ -generalized statistics.
hep-ph0 citations
13
Status of the strong $C P$ problem
Wen-Yuan Ai🇨🇳
The strong $C P$ problem remains one of the major open questions in the Standard Model of particle physics. Its best-known solution is the Peccei--Quinn mechanism, which predicts a new pseudoscalar boson, the QCD axion. In recent years, alternative solutions and new perspectives on the foundations of the strong $C P$ problem have also received renewed attention. In this review, we provide a pedagogical account of the underlying physics and summarise the current theoretical and phenomenological status of the problem.
hep-phastro-ph.COhep-lathep-th0 citations
14
Reanalysis of exclusive charmonium production at the $B$ factories
Xu-Dong Huang🇨🇳 · Jian-Xiong Wang🇨🇳
In this paper, we present a comprehensive analysis of the next-to-next-to-leading-order (NNLO) QCD corrections to the exclusive processes $e^{+} e^{-} \to J / ψ + η_{c}$ , $e^{+} e^{-} \to J / ψ + χ_{c J}$ , $e^{+} e^{-} \to η_{c} + γ$ , and $e^{+} e^{-} \to χ_{c J} + γ$ $(J = 0, 1, 2)$ at the $B$ factories, comparing perturbative expansions truncated at the amplitude level and squared-amplitude level. Our results show that the amplitude-level prescription improves the perturbative convergence, with the NNLO/LO ratios lying closer to the corresponding NLO/LO ratios than those in the squared-amplitude-level prescription. This improvement is particularly pronounced for $e^{+} e^{-} \to χ_{c 2} + γ$ , where the NNLO prediction is about 27\% of the LO result in the amplitude-level prescription, compared with only 12\% in the squared-amplitude-level prescription. The amplitude-level prescription also reduces the residual renormalization scale dependence, particularly for the $P$ -wave channels. Finally, the NNLO predictions are generally in good agreement with the available Belle and BaBar measurements and have central values closer to the data than those obtained with the squared-amplitude-level prescription. For channels with only upper limits, the predictions from both prescriptions are consistent with the experimental constraints, except for $e^{+} e^{-} \to η_{c} + γ$ , where both NNLO predictions remain above the current upper limit.
hep-ph0 citations
15
Mixing-angle sensitivity of inclusive $Ξ_{b c}$ and $Ω_{b c}$ lifetimes
Hai-Yang Cheng🇹🇼 · Chia-Wei Liu🇨🇳 · Fanrong Xu🇨🇳
We study the inclusive lifetimes of $Ξ_{b c}^{+}$ , $Ξ_{b c}^{0}$ , and $Ω_{b c}^{0}$ , with emphasis on the mixing between the spin-zero and spin-one $b c$ -diquark configurations. The relevant hadronic matrix elements are evaluated in both the homogeneous bag model (HBM) and the nonrelativistic quark model (NRQM). At the benchmark mixing angles of $- 23. 0^{\circ}$ for $Ξ_{b c}$ and $- 23. 5^{\circ}$ for $Ω_{b c}$ , the corresponding lifetime triplets are $(τ_{Ξ_{b c}^{+}}, τ_{Ξ_{b c}^{0}}, τ_{Ω_{b c}^{0}}) = (0.42 1_{- 0.093}^{+ 0.093}, 0.07 5_{- 0.010}^{+ 0.035}, 0.22 3_{- 0.043}^{+ 0.074}) ps$ in the HBM and $(τ_{Ξ_{b c}^{+}}, τ_{Ξ_{b c}^{0}}, τ_{Ω_{b c}^{0}}) = (0.36 7_{- 0.070}^{+ 0.076}, 0.10 0_{- 0.014}^{+ 0.032}, 0.22 9_{- 0.042}^{+ 0.066}) ps$ in the NRQM. Relative to the unmixed spin-one reference points, the $Ξ_{b c}^{0}$ and $Ω_{b c}^{0}$ lifetimes decrease by approximately $17%$ - $19%$ . Neither the minimum nor the maximum of the central lifetime curves occurs at a pure $S_{b c} = 0$ or $S_{b c} = 1$ configuration; the extrema instead lie at mixed angles with $∣ ϕ_{B} ∣ ≃ 2 7^{\circ}$ - $6 3^{\circ}$ . The two pure-spin limits alone are therefore insufficient to characterize the full mixing-angle dependence.
hep-phhep-ex0 citations
16
Flavor-Violating Higgs and Top Decays in the Type 1B Flavorful Two-Higgs-Doublet Model with a Twist
Ti-Bin Hou🇨🇳 · Zheng Li🇨🇳 · Yu-Ju Peng🇨🇳 · Jin-Lei Yang🇨🇳 · Hao-Ran Ma🇨🇳 · Tai-Fu Feng🇨🇳
We study flavor-violating decays of the SM-like Higgs boson and rare top decays in the Type 1B realization of the flavorful two-Higgs-doublet model with a twist, focusing on $h \to s b$ , $h \to d b$ , $h \to u c$ , $h \to μτ$ , $h \to e τ$ , $h \to e μ$ , $t \to c h$ , and $t \to u h$ . We present the relevant amplitude and branching-ratio formulae, include one-loop vertex corrections, and impose constraints from Higgs signal-strength measurements, electroweak precision tests, meson mixing, $B \to X_{s} γ$ , direct HFV searches and CLFV constraints, including $μ - e$ conversion. The surviving parameter space favors $\BR (h \to s b) ≫ \BR (h \to d b)$ , $\BR (t \to c h) ≫ \BR (t \to u h)$ , and $\BR (h \to μτ) ≫ \BR (h \to e τ) \sim \BR (h \to e μ)$ in the lepton sector. One-loop effects usually preserve these hierarchies, but can modify individual channels through different mechanisms: sizable destructive tree--loop interference can reduce $h \to s b$ enough to yield rare $\BR_{1L} (h \to d b) > \BR_{1L} (h \to s b)$ points, whereas the large relative corrections found in rare top decays mainly reflect strong SM-like alignment suppressing the tree-level amplitudes.
hep-ph0 citations
17
Understanding IR singularities in the Loop-Tree Duality
Germán Rodrigo🇪🇸 · Leandro Cieri🇪🇸 · Prasanna K. Dhani🇪🇸 · Roger J. Hernández-Pinto🇲🇽 · Jorge J. Mart\'ınez de Lejarza🇪🇸 · Salvador A. Ochoa-Oregon🇪🇸 · Konstantinos Pyretzidis🇪🇸 · Selomit Ram\'ırez-Uribe🇲🇽 · David F. Renter\'ıa-Estrada🇪🇸 · Andrés E. Renter\'ıa-Olivo🇪🇸 · José R\'ıos-Sánchez🇪🇸 · German F.R. Sborlini🇪🇸 · Surabhi Tiwari🇪🇸 · Juan P. Uribe-Ram\'ırez🇲🇽
One of the main advantages of the Loop-Tree Duality representation of scattering amplitudes is that it makes the origin of infrared and threshold singularities particularly transparent. This talk reviews recent progress in describing how singularities emerge and cancel at the level of scattering and vacuum amplitudes, discusses a novel strategy to efficiently construct finite integrals, and presents a complementary perspective based on encoding the underlying causal and singular structure in terms of qubits and quantum circuits.
hep-phhep-thquant-phPoS(2026)·0 citations
18
The Type-I Seesaw as a Relativistic Fermionic Proximity Effect: Spectral Moments, EFT Consistency, and Sterile-Sector Reconstruction
Jianlong Lu🇸🇬
We formulate the type-I seesaw as a relativistic fermionic proximity effect in the exact active-sector two-point kernel. Active neutrinos have no renormalizable gauge-invariant Majorana mass and couple by lepton-number-conserving Yukawa hybridization to a sterile Majorana pairing kernel. Integrating out the sterile fields gives a nonlocal Nambu-Gorkov embedding self-energy. In a sterile Takagi basis its anomalous and normal flavor responses are $A (Q^{2}) = \sum_{i} M_{i} y_{i} y_{i}^{T} / (Q^{2} + M_{i}^{2})$ and $B (Q^{2}) = \sum_{i} y_{i} y_{i}^{†} / (Q^{2} + M_{i}^{2})$ , respectively. Their low-energy expansions generate correlated lepton-number-violating and lepton-number-conserving moment towers. The leading moments reproduce the Weinberg coefficient and the dimension-six kinetic operator. Both towers share one sterile mass set; its positive normal support supplies a common annihilator, although anomalous residues can cancel at exact degeneracy. We prove normal block-Hankel positivity and positivity of a dimensionally rescaled mixed Nambu-Hankel sequence. The latter gives matrix Cauchy-Schwarz inequalities between lepton-number-conserving and lepton-number-violating data and can reveal paired directions hidden by a degenerate normal residue. Isolated nondegenerate pole residues satisfy an additional nonlinear compatibility identity. These results yield tree-level EFT consistency tests and a matrix-pencil reconstruction of visible pole and aggregate-residue data; selecting a unique ultraviolet Lagrangian requires additional information about sterile-basis multiplicities. An exact one-generation example distinguishes the static Schur-complement kernel from the physical Takagi pole mass. The proximity structure applies without a Fermi surface or condensate, and Nambu doubling introduces no new physical degrees of freedom.
hep-phmath-phmath.MP0 citations
19
Neutrino masses and mixing angles in the Plan B Model
Ben Allanach🇬🇧 · Prabhoda Chandra Sarjapur🇬🇧
The Plan B Model was proposed to improve the global fit quality of the Standard Model to observables involving the $b \to s ℓ^{+} ℓ^{-}$ transition whilst simultaneously providing a qualitative explanation for the small magnitudes of some off-diagonal quark mixing matrix entries. The model is based on applying an additional spontaneously broken $U (1)_{3 B_{3} - L_{e} - 2 L_{μ}}$ gauge symmetry to the Standard Model with family-dependent fermion charges. Right-handed neutrino fields are present and cancel gauge anomalies. We investigate the implications of the Plan B Model for neutrino masses and mixing angles. The model naturally suggests a Froggatt-Nielsen mechanism for neutrino masses and mixing hierarchies. We find that an implementation of the Froggatt-Nielsen mechanism works when additional suppression is present from a clockwork mechanism. We show how current neutrino oscillation data can be fit with order unity fundamental dimensionless couplings.
hep-ph0 citations
20
Radiative pion-pair production in disperon QED
Yizhou Fang🇨🇭 · Sophie Kollatzsch🇨🇭 · Adrian Signer🇨🇭 · Max Zoller🇨🇭
Based on the previously developed disperon QED method for incorporating data input into loop processes in Monte Carlo codes, we calculate $ee \to π π γ$ at NLO and include the pion vector form factor within the form-factor scalar QED approximation wherever it is physically justified. By also considering contributions beyond, for which the form-factor scalar QED approach is less well justified, we gain insight into the associated theory uncertainty for selected experimental scenarios. All calculations are implemented and made available within the Monte Carlo framework McMule.
hep-ph0 citations
21
Electric Dipole Moments in the CP-violating Generational Three-Higgs-Doublet Model
Hao-Ran Ma🇨🇳 · Ti-Bin Hou🇨🇳 · Jin-Lei Yang🇨🇳 · Tai-Fu Feng🇨🇳
Motivated by the Yukawa interactions in the CP-violating Generational Three-Higgs-Doublet Model (G3HDM), we investigate the electric dipole moments (EDMs) of the $b$ quark, $c$ quark, electron, neutron, and mercury atom, imposing constraints from the observed $125 GeV$ Higgs signals, flavor physics, and rare $B$ -meson decays. We find that the $b$ quark, neutron, and mercury EDMs are predominantly controlled by top-enhanced charged-Higgs amplitudes, whose internal cancellations are generally weak. Meanwhile, pronounced pairwise cancellations between nearly degenerate neutral Higgs states occur in the $c$ quark, electron, neutron, and mercury EDMs. Using degenerate perturbation theory, we show that these cancellations originate from approximate relations among the neutral-Higgs mixing-matrix elements, which enforce the anti-alignment of the corresponding CP-odd coupling invariants.
hep-ph0 citations
22
Investigating three-body resonances in $α α Ω/ Ω_{ccc}$ clusters within the $_{Ω/ Ω_{ccc}}^{9} Be$ nucleus
Hao Zhou🇨🇳 · Xiang Liu🇨🇳
We investigate the bound and resonant states of the $α + α + Ω$ and $α + α + Ω_{ccc}$ three-body systems, corresponding to $_{Ω}^{9} Be$ and $_{Ω_{ccc}}^{9} Be$ , within the Gaussian expansion method combined with the complex scaling method. The $α Ω$ and $α Ω_{ccc}$ interactions are constructed by folding the $N Ω$ and $N Ω_{ccc}$ potentials obtained from lattice QCD calculations by the HAL QCD Collaboration with the nucleon density distribution of the $α$ particle. The uncertainty associated with the $α$ -particle matter radius is also examined. For the $Ω$ sector, the strong $N Ω$ attraction generates deeply bound $0_{1}^{+}$ , $2_{1}^{+}$ , and $4_{1}^{+}$ states in $_{Ω}^{9} Be$ , accompanied by a pronounced contraction of the $α α$ core, demonstrating a strong gluelike effect of the $Ω$ baryon. An unconventional inversion between the $0_{1}^{+}$ and $4_{1}^{+}$ levels is also predicted. In contrast, the $Ω_{ccc}$ baryon produces considerably weaker attraction: the $0_{1}^{+}$ state of $_{Ω_{ccc}}^{9} Be$ is weakly bound, whereas the $2_{1}^{+}$ and $4_{1}^{+}$ states remain resonances. Their resonance energies and widths exhibit a clear dependence on the strength of the $α Ω_{ccc}$ interaction. These results reveal qualitatively different gluelike behaviors of the $Ω$ and $Ω_{ccc}$ baryons and provide predictions for the spectroscopy of exotic multistrange and triply charmed hypernuclei.
hep-phnucl-th0 citations
23
Amplitude structure of $3 \to 3$ scattering in a Mandelstam variable representation
Xu Zhang🇨🇳 · Feng-Kun Guo🇨🇳
We construct a dispersive representation of the relativistic $3 \to 3$ scattering amplitude for three identical spinless particles in the $S$ -wave. The two-particle subenergy, instead of the total energy, is used as the dispersive variable. This choice keeps the physical dispersive contour free of the kinematical cuts that complicate total-energy dispersion relations. By separating discontinuities across the two-particle subenergy cuts from that across the three-body cut, we derive a linear integral equation with one-particle exchange as the driving term. We further show that the solution satisfies three-body unitarity as a consequence of two-body unitarity, analyticity, and crossing symmetry. For pair-wise interactions, this representation can be rewritten into the form used for isobar-spectator scattering. Finally, we give prescriptions for contour deformation and the subtraction of poles in the two-body subsystem amplitudes, which continue the amplitude onto adjacent unphysical Riemann sheets and thus provide direct access to the analytic structure relevant for three-body resonance poles.
hep-phhep-latnucl-th0 citations
24
NNLL fit of the transverse-momentum-dependent distribution of unpolarised gluons to LHCb data on $J / ψ$ -pair production
D. Boer🇳🇱 · J. Bor🇳🇱 · A. C. Serri🇵🇱 · M. G. Echevarria🇪🇸 · J. P. Lansberg🇫🇷 · S. F. Romera🇪🇸 · P. Taels🇫🇷
We perform the first fit of the unpolarised gluon transverse-momentum-dependent distribution $f_{1}^{g}$ up to next-to-next-to-leading-logarithmic accuracy to the double-differential distribution in the invariant mass and transverse momentum of the latest $J / ψ$ -pair production LHCb data. We review previous attempts to describe the older $J / ψ$ -pair LHCb data using $f_{1}^{g}$ , and discuss two novel methodologies which allow us to account in the fit for both the perturbative and PDF uncertainties to construct $f_{1}^{g}$ in the perturbative region. It turns out that the consideration of these uncertainties is crucial for a meaningful fit to such low-scale gluon-sensitive data.
hep-ph0 citations
25
Update of the Standard-Model prediction for $B ˉ \to X_{s} γ$
Tobias Huber🇩🇪
We report on two recent calculations on the inclusive radiative decay $B ˉ \to X_{s} γ$ , notably multi-parton contributions at NLO and the $Q_{1, 2} - Q_{7}$ interference at NNLO for the physical value of the charm-quark mass. The former calculation formally completes $B ˉ \to X_{s} γ$ at NLO in QCD at leading power, the latter removes a long-standing $\pm 3%$ uncertainty arising from interpolation in $m_{c}$ . The updated Standard-Model prediction for the CP- and isospin-averaged branching ratio reads $B_{s γ}^{SM} = (3.54 \pm 0.14) \times 1 0^{- 4}$ for photon energies $E_{γ} > 1.6 GeV$ in the $B$ -meson rest frame. This value is in good agreement with the current experimental average $B_{s γ}^{exp} = (3.49 \pm 0.19) \times 1 0^{- 4}$ .
hep-ph0 citations
26
Saturation effects in diffractive deep inelastic scattering
Jani Penttala🇺🇸 · Christophe Royon🇺🇸 · Jarno Vierros🇺🇸
We study the production of $c$ and $b$ quarks in photon-induced processes as a probe of gluon saturation, with a focus on the high-energy region accessible in ultra-peripheral collisions (UPCs) at the LHC. We compare predictions for inclusive and diffractive heavy quark production with and without saturation effects by using the nonlinear Balitsky--Kovchegov and the linear Balitsky--Fadin--Kuraev--Lipatov equations for the evolution of the dipole amplitude. The percentage of coherent diffractive events is predicted to be $20%$ in the saturation model, which is approximately twice as large as predictions based on parton distribution functions and shadowing. This indicates that measurements of diffractive heavy quark production in UPCs may provide a sensitive probe for distinguishing linear and nonlinear regimes of quantum chromodynamics.
hep-phhep-exhep-thnucl-ex+10 citations
27
Deviation from $μ - τ$ reflection symmetry under radiative corrections in the minimal seesaw framework
Prokash Pegu🇮🇳 · Chandan Duarah🇮🇳
The $μ$ - $τ$ reflection symmetry predicts a maximal atmospheric mixing angle, $θ_{23} = π /4$ , and Dirac CP phase, $δ = π /2$ or $3 π /2$ . Recent global analyses indicate small but significant deviations from these predictions, suggesting that the symmetry is approximate and requires breaking. Motivated by this, we study the breaking of $μ$ - $τ$ reflection symmetry induced by radiative corrections in the minimal seesaw framework, assuming the symmetry to be exact at the high-energy seesaw scale $Λ_{μτ} = 1 0^{14} GeV$ . A distinctive feature of the minimal seesaw is that one light neutrino remains massless, leaving only one physical Majorana CP phase. Starting from the integral solution of the one-loop RGE for the effective Majorana neutrino mass matrix, we derive analytical expressions for the low-energy neutrino parameters at $Λ_{EW} = 172.76 GeV$ in terms of their high-energy counterparts. We then numerically estimate the low-energy parameters within the MSSM, taking $Λ_{s} = 1 TeV$ and $tan β = 10$ , $30$ and $50$ . The analysis is performed separately for Normal Order (NO) and Inverted Order (IO). We find that the predicted neutrino masses and mixing parameters are consistent with current experimental data in both scenarios. The sum of neutrino masses, Jarlskog invariant $J$ , and effective Majorana mass $∣ ⟨ m ⟩_{ee} ∣$ also satisfy current experimental constraints. Finally, we estimate the amount of deviations of the low-energy neutrino parameters from their high-energy values and investigate their dependence on $tan β$ . We find that the magnitude of these deviations increases with increasing $tan β$ for both NO and IO.
hep-ph0 citations
28
Angular correlations and polarization in $Z$ +jet production at the LHC
Francesco Giovanni Celiberto🇪🇸 · Francesca Lonigro🇪🇸
Precision studies at the LHC increasingly require theoretical control over QCD radiation beyond fixed-order perturbation theory, particularly in final states characterised by large separations in rapidity. High-energy logarithms can generate corrections at the ten-percent level even for electroweak-scale observables, as recently observed in Higgs production, motivating their systematic inclusion in precision analyses. We investigate this regime through Drell $-$ Yan plus jet production, with particular emphasis on $Z$ -boson final states and their angular and polarisation structure. High-energy logarithms are resummed at next-to-leading logarithmic accuracy and consistently combined with NLO fixed-order information. Beyond inclusive rapidity and transverse-momentum spectra, the framework resolves the azimuthal harmonic content of the process, whose pattern is reshaped by the transition from leading- to next-to-leading-order emission dynamics. We further develop the JETHAD $-$ DYnamis $-$ POWHEG strategy towards realistic lepton-level predictions, retaining spin correlations, decay-angle information, and experimentally accessible kinematics. This programme establishes $Z$ +jet production as a precision probe of high-energy QCD dynamics for Run~3 and the HL-LHC.
hep-phhep-ex0 citations
29
Spin alignment of vector mesons in a plasma at finite density
Fei Wang🇨🇳 · Zi-qiang Zhang🇨🇳
We study the spectral functions and spin alignment of $J / ψ$ and $ϕ$ mesons at finite density within a soft wall holographic model that provides the quark-gluon plasma background, with vector mesons represented by bulk vector fields. We derive the relation between the production rates in distinct spin channels and the corresponding in-medium spectral functions, and examine their dependence on the chemical potential, meson momentum, and temperature. We analyze the spin alignment induced by the motion of the vector meson relative to the thermal bath. At $T = 0.15 GeV$ , the $J / ψ$ spectral function exhibits a clear resonance peak, indicating that the $c c ˉ$ pair can still form a quasistable bound state. As the chemical potential increases, this peak becomes lower and broader, signaling enhanced dissociation in the medium. For the $ϕ$ meson at the same temperature, no pronounced peak is observed, indicating substantial melting; its spectral function thus better characterizes the distribution of unstable $s s ˉ$ pairs in the thermal environment. At $T = 0.15 GeV$ , the helicity-frame spin alignment parameter $ρ_{00}$ shows a positive deviation from $1/3$ for the $J / ψ$ and a negative one for the $ϕ$ meson. A finite chemical potential alters these deviations, reducing the magnitude for the $J / ψ$ while increasing it for the $ϕ$ meson.
hep-ph0 citations
30
Addendum: Production of $π^{+} π^{-}$ pairs in diffractive photon-proton and in proton-proton collisions revisited, in particular concerning the Drell-Söding contribution
Piotr Lebiedowicz🇵🇱 · Otto Nachtmann🇩🇪 · Antoni Szczurek🇵🇱
We update our analyses concerning the non-resonant (Drell-Söding) contribution to the reaction $γ^{(*)} p \to π^{+} π^{-} p$ , now including general vertex functions for the coupling of pomeron, $f_{2 R}$ , and $ρ_{R}$ , to pions. This takes into account the off-shellness of the pions. We present a comparison of our tensor-pomeron model, including our new Drell-Söding and $ρ$ , $ω$ vector-meson contributions, with data for the $γ p \to π^{+} π^{-} p$ reaction measured by the ZEUS and H1 Collaborations. We find very good agreement of our theory with the experimental data for the $π^{+} π^{-}$ invariant mass ( $M_{π π}$ ) and for angular distributions. Here we restrict our analysis to the region $M_{π π} ≲ 1.2$ GeV. For higher values of $M_{π π}$ we will have to consider production of higher-mass mesons. The purpose of the present article is to show that our tensor-pomeron model gives a very good fit to the so-called skewing of the $ρ$ -resonance contribution in photoproduction. In fact, it is an old problem/puzzle to understood the difference of the shapes of the $M_{π π}$ distributions in the region of the $ρ (770)$ resonance in $e^{+} e^{-}$ annihilation and photoproduction. We think that with our results we have obtained for this problem a solution which is very satisfactory from the Quantum-Field-Theory point of view. Our results are also relevant for central-exclusive $π^{+} π^{-}$ production in ultraperipheral $pp$ , A $p$ , and AA collisions at the LHC and for photo- and electroproduction of $π^{+} π^{-}$ at future electron-proton/ion colliders, EIC and LeHC.
hep-ph0 citations
31
On the Nature of $X (2370)$
Di Ben🇨🇳 · Li-Ke Yang🇨🇳 · Bing-Song Zou🇨🇳
Recently, the BESIII Collaboration claimed that their observed $X (2370)$ ( $J^{P C} = 0^{-+}$ ) is predominantly a glueball state based on several arguments. However, we find these arguments to be flawed and the conclusion unjustified. Instead, we demonstrate that all observed properties of the $X (2370)$ can be naturally explained by a $Σ ˉ Σ$ molecule dominated state.
hep-ph0 citations
32
Phase structure of magnetized quark matter at imaginary chemical potential
J.P. Carlomagno🇦🇷 · D. Gómez Dumm🇦🇷 · N.N. Scoccola🇦🇷
We investigate the phase structure of magnetized quark matter within a nonlocal SU(2) Polyakov-Nambu-Jona-Lasinio model. Our work focuses on the interplay between temperature and imaginary chemical potential in the presence of an external uniform magnetic field, with emphasis on the deconfinement and Roberge-Weiss transitions. We analyze the dependence of the relevant critical temperatures on the external field, and we explore the sensitivity of the phase structure to different Polyakov loop effective potentials. Our results show qualitative agreement with lattice QCD findings, reproducing inverse magnetic catalysis in the chiral sector and a decreasing behavior of the Roberge-Weiss transition temperature with increasing magnetic field.
hep-ph0 citations
33
Probing jet medium interaction with generalized projected energy correlators
Balbeer Singh🇺🇸
We study medium modifications to generalized projected energy correlators, referred to as $ν$ -correlators, measured on jets in heavy-ion collisions. While the vacuum distributions of these correlators exhibit a characteristic $1/ ν$ enhancement, we show that in a dense medium this behavior is regulated within both the BDMPS-Z and semi-classical approximations as $ν \to 0$ . As a result, contributions from medium-induced emissions become parametrically suppressed relative to the vacuum baseline. We observe a similar trend in the simulated events generated with JEWEL. We find that while the large angle enhancement is qualitatively similar across different values of $ν$ , the small angle distribution changes drastically between $ν < 1$ and $ν > 1$ . This indicates that small angle modifications, primarily driven by jet energy loss, are imprinted differently across $ν$ -correlators. In particular, for $ν < 1$ the small angle enhancement is less prominent which suggests that these correlators may provide improved sensitivity to medium modifications in the large angle region.
hep-ph0 citations
34
Inelastic Dark Matter Signature at High Recoil Energy in LUX-ZEPLIN and CRESST
Liangliang Su🇩🇪 · Jin Min Yang🇨🇳 · Wen-Na Yang🇨🇳
The LUX--ZEPLIN Collaboration recently reported one event at $E_{nr} = 248 \pm 23 keV$ with an exposure of $2.84 tonne \cdot yr$ . In this Letter, we interpret this feature using endothermic dark matter (DM). We consider both direct scattering of the surviving ground-state halo component and the contribution of excited states produced by terrestrial upscattering. Our calculations show that explaining the high-energy event requires $m_{χ} ≳ 500 GeV$ and a mass splitting of $O (300) keV$ , for which the production of excited states inside the Earth is kinematically forbidden. For $σ ˉ_{n} = 1 0^{- 37} c m^{2}$ , an illustrative two-bin likelihood analysis yields a representative best-fit point at $(m_{χ}, δ) ≃ (1.105 TeV, 350 keV)$ . The preferred parameter region may be tested by the planned CRESST upgrade.
hep-ph27 citations
35
Gravitational Waves from Reheating beyond Instantaneous Thermalization
Kyohei Mukaida🇯🇵 · Tenta Tsuji🇯🇵
We study gravitational-wave production during perturbative reheating without assuming instantaneous thermalization of the inflaton decay products. The injected energetic particles thermalize through an in-medium cascade of nearly collinear splittings subject to the Landau-Pomeranchuk-Migdal effect and are ultimately isotropized by elastic scatterings near the thermal scale. The non-thermal hard population present before complete thermalization produces an additional gravitational-wave component through hard-soft scatterings, with $Ω_{GW} \propto f^{1/2}$ below the injection-scale turnover. The same isotropization erases the directional information underlying the vacuum $1/ k$ bremsstrahlung soft pole, changing the deep-infrared spectrum from $Ω_{GW} \propto f$ to $Ω_{GW} \propto f^{3}$ .
hep-phastro-ph.COhep-th0 citations
36
Higgsino Above the Sea of Fog
JiJi Fan🇺🇸 · Matthew Reece🇺🇸
Higgsino dark matter is a classic, but still viable, weakly-interacting massive particle (WIMP) scenario that could point to supersymmetry, a new spacetime symmetry of nature. It is a simple realization of the "inelastic dark matter" mechanism, where its scattering off a nucleus occurs between two nearly degenerate states. Intriguingly, very recently the LZ collaboration reported a single nuclear recoil event at a high recoil energy. Assuming that this event is a dark matter candidate, it could be explained by higgsino dark matter, e.g., a 1.1 TeV thermal higgsino with a mass splitting of order hundreds of keV. The mass splitting required is very sensitive to the extreme high speed tail of the local dark matter velocity distribution, and thus susceptible to astrophysical uncertainties: the standard halo model prefers ~350 keV, while a model incorporating Large Magellanic Cloud effects prefers ~500 keV (a rough estimate based on partial information about a particular simulation). A much better understanding of the high speed tail is needed to evaluate whether the parameter space is consistent with an IceCube constraint on the annihilation of dark matter captured by the Sun. In any case, the mass splitting of several hundred keV implies that the electroweak gauginos and heavy Higgs scalars in supersymmetry have to be at a much higher scale ~10^{3-4} TeV. We discuss possible UV completions to generate a SUSY spectrum in which all superpartners are at a common scale, except for a much lighter higgsino mass $μ$ . Besides the thermal benchmark, we comment on possible non-thermal cosmological scenarios of higgsino dark matter with gravitino and modulus decays. The higgsino dark matter scenario could also be searched for at other complementary probes such as indirect detection and future colliders. One striking LZ event may herald an exciting future of further experimental developments.
hep-ph27 citations
37
Higgsino Dark Matter Interpretation of the LUX-ZEPLIN 248 keV Nuclear-Recoil Event
Katherine Freese🇺🇸 · Dionysios P. Theodosopoulos🇺🇸
We propose Higgsino dark matter as a potential interpretation of the $248 keV$ nuclear-recoil event of interest reported by the LUX-ZEPLIN (LZ) experiment. LZ studied several rare background processes and detector effects in detail, but did not identify any as a likely explanation of the event. A nearly pure Higgsino with mass $m_{H} \sim 1 TeV$ naturally realizes inelastic dark matter through the off-diagonal $Z$ coupling of two nearly degenerate neutral Majorana states separated by a mass splitting $δ$ . The same electroweak interaction fixes the inelastic Higgsino-nucleon scattering cross section, rather than leaving it as a free parameter. We show that the predicted Higgsino inelastic scattering cross section approaches the published LZ two-sided 90% confidence interval for $δ \sim 350 keV$ .
hep-phastro-ph.COhep-th30 citations
38
TeV Higgsino Dark Matter from LZ Nuclear Recoil to Fermi-LAT Gamma Rays
Lei Wu🇨🇳 · Yang Zhang🇨🇳 · Bin Zhu🇨🇳
The Higgsino dark matter of the minimal supersymmetric standard model is one of the most minimal and canonical WIMP candidates. We demonstrate that this classic candidate can account for both the high-energy nuclear-recoil excess reported by the LZ experiment and the mild preference in the 14 years of FermiLAT Galactic-center data, with the relic abundance fixing the Higgsino dark matter mass near 1.1 TeV and the recoil spectrum selecting a mass splitting of a few hundred keV. Together with the 10-year IceCube solar-neutrino constraint, the Higgsino interpretation further pins down a viable region of parameter space. It predicts a Galactic-center gamma-ray line and endpoint signal near the present H.E.S.S. sensitivity and within CTAO's projected reach, making this classic candidate testable in the near future.
hep-ph29 citations
39
Fermionic Dark Matter Absorption and the High-Energy Event in LUX-ZEPLIN
Yuanchao Lou🇨🇳 · Chih-Ting Lu🇨🇳
The LUX-ZEPLIN (LZ) experiment has reported a single candidate event in the high-energy nuclear recoil window $248 \pm 32.5 keV_{nr}$ with an exposure of $2.84 ton \cdot yr$ , while the low-energy spectrum remains consistent with background expectations. We demonstrate that this excess can be naturally explained by the neutral-current absorption of fermionic dark matter on xenon nuclei. For a dark matter mass $m_{χ} ≃ 247 MeV$ , the coherent absorption process produces a monoenergetic nuclear recoil at $E_{R} ≃ 248 keV_{nr}$ . At this momentum transfer, the absorption process enters the incoherent regime, where scattering off individual nucleons produces a broad recoil spectrum extending from $\sim 200 keV$ to $100.2 MeV$ . We show that a single effective field theory coupling can simultaneously produce one event in the $248 \pm 32.5 keV_{nr}$ window while remaining consistent with the non-observation of events in neighboring energy regions. The required single-nucleon absorption cross section is $σ_{χ N}^{NC} = 1.07 \times 1 0^{- 46} cm^{2}$ , corresponding to an effective field theory scale $Λ ≃ 11.5 TeV$ . However, a recasting analysis of KamLAND data on the neutron-emission channel $χ +^{12} C \to ν + n +^{11} C^{*}$ excludes this benchmark parameter space, establishing a significant tension between the LZ excess interpretation and existing constraints from large-volume scintillator detectors. We discuss the implications of this tension and prospects for resolving it with future dedicated high-energy analyses.
hep-phhep-ex30 citations
40
Decisive evidence for a global cosmic-ray feature in gamma-ray data
Fernando Valenciano · Pedro De la Torre Luque🇪🇸 · Daniele Gaggero🇮🇹 · Jorge Martin Camalich🇪🇸
We analyze 17 years of Fermi-LAT data to study the diffuse $γ$ -ray emission along the Galactic plane and its connection to cosmic-ray (CR) propagation. Accounting for correlated instrumental systematics, we find decisive evidence for a spectral break at $\sim 20 - 30$ GeV, present across the inner Galactic disk, with a preference of $Δ χ^{2} = 39.78$ ( $4.44 σ$ global). The energy and amplitude of this feature are in striking agreement with the spectral feature observed in local CR nuclei, indicating that it is a global property of the Galactic disk rather than a local phenomenon. The measured slope change, $Δ γ ≃ 0.20$ , is consistent with local CR data and with expectations from a transition in the CR diffusion regime from Kolmogorov to Kraichnan turbulence. Our results provide strong evidence that diffuse $γ$ -ray emission along the Galactic disk is dominated by $π^{0} -$ decay emission up to a hundred GeV. These findings provide key insights into the origin of the CR spectral hardening and the propagation of CRs throughout the Galaxy, and illustrate how this multimessenger approach can be used to probe the origin of features in the CR spectra, such as the long-studied CR Knee.
↳ astro-ph.HEastro-ph.GAhep-ph0 citations
41
Subleading Collinear Limits of Yang-Mills Amplitudes from Gravity
Jin Dong🇩🇪 · Stephan Stieberger🇩🇪
We show that the subleading collinear sector of Yang-Mills (YM) amplitudes is controlled by ordinary Einstein-Yang-Mills (EYM) amplitudes and their higher-derivative corrections. The complete set of strict subleading collinear limits associated with an equal-helicity collinear pair can be extracted from open-closed string disk amplitudes. The latter generate $\frac{1}{2} (n - 3)!$ BCJ-like relations with non-linear kinematic coefficients, reducing the $(n - 3)!$ collinear data to a basis of dimension $\frac{1}{2} (n - 3)!$ . This reduced basis can be represented by gravitational amplitudes in EYM theories and by their higher-derivative open-string corrections. At multiplicity $n$ this gravitational basis consists of the $(n - 4)!$ independent EYM subamplitudes together with $\frac{1}{2} (n - 5) (n - 4)!$ higher-order corrections involving one graviton and $n - 2$ gluons. The resulting decomposition is governed by unsigned Stirling numbers of the first kind: the ordinary EYM amplitudes correspond to the sector $[1 n - 3]$ , the higher-order BCJ-like relations to even sectors $[2 j n - 3]$ , and the higher-derivative EYM corrections to odd sectors $[2 j + 1 n - 3]$ with $j \geq 1$ .
↳ hep-thgr-qchep-phmath.AG+11 citation
42
Probing Dense Nuclear Matter at Small-x: A workflow for a global analysis framework
Junaid S. Khan · Rebecca L. Lustberg · Fredrick Olness🇺🇸 · Peter Risse🇺🇸 · Bjoern Schenke🇺🇸 · Brandon Stevenson
The dipole model provides a powerful framework for describing high-energy nuclear interactions, particularly in the regime of dense gluonic matter. However, accurately evolving the dipole--nucleus scattering amplitude remains a major computational challenge because it is governed by nonlinear QCD evolution equations. To address this, we investigate a machine learning (ML) model as an efficient surrogate for the conventional numerical evolution. These ML-based approximations dramatically reduce the computational cost of global analyses while maintaining the accuracy required to describe a broad range of experimental data. We systematically evaluate the ML results for accuracy, computational efficiency, and ability to capture essential features of dipole evolution in nuclear environments. These computational advancements will enable global analyses of diverse datasets within both the dipole and parton model frameworks, providing a more rigorous probe of nuclear structure in the dense regime. Comparing both descriptions within a common fitting framework can provide precise constraints on the gluon distributions and advance our understanding of the quark and gluon structure of nuclei, particularly in the small-x region.
↳ nucl-thhep-ph0 citations
43
A Data-Driven Model for $r$ -Process Production Patterns
Chen-Qi Li🇺🇸 · Yong-Zhong Qian🇺🇸 · Axel Gross🇺🇸 · Zewei Xiong🇩🇪
Using the elemental abundances in 68 metal-poor (MP) stars, we present a data-driven model for $r$ -process production patterns covering Sr to U. We show that essentially all the $r$ -process patterns in those and other test stars can be adequately explained as mixtures of Patterns 1 and 2, which provides theoretical insights into the empirical categories of limited- $r$ , $r$ -I, and $r$ -II stars. We carry out an extensive survey of the yield templates produced by parametric $r$ -process calculations. We propose that Pattern 2 may be dominated by a single template and points to regularity in $r$ -process production by a subset of neutron star mergers (NSMs), while Pattern 1 is the average superposition of multiple templates and reflects production by other NSMs and perhaps also some magneto-rotational supernovae. We raise possible systematic issues with abundance ratios for elements measured in different ionization states, and highlight the need for examining the Os, Ir, and Pt measurements for HD~122563, which is dominated by Pattern 1 with a prominent Pt peak in our model. If this result is confirmed, the meaning of the limited- $r$ category requires drastic revision. Further measurements of a wider range of $r$ -process elements in a larger sample of MP stars are critical to test and improve our model.
↳ astro-ph.SRhep-phnucl-th0 citations
44
Perturbations and stability of black holes with static scalar hair in general GLPV theories
Petarpa Boonserm🇹🇭 · Antonio De Felice🇯🇵 · Ratchaphat Nakarachinda🇹🇭 · Shinji Tsujikawa🇯🇵 · Pitayuth Wongjun🇹🇭
We derive the background equations and complete odd- and even-parity quadratic actions for static, spherically symmetric black holes with radial scalar hair in general quartic-quintic Gleyzes-Langlois-Piazza-Vernizzi (GLPV) theories, including Horndeski. On regular, nondegenerate branches, the formulation applies across Killing horizons and yields local no-ghost conditions and radial and angular eikonal characteristics. Tensor modes in both parity sectors share the same squared radial speed. When the radial coordinate is timelike, generic antisymmetric mixing induces nonstandard large-multipole scaling for both even-parity angular branches. Requiring both branches to have finite, nonzero eikonal phase speeds selects the Horndeski-related compatibility condition between the quartic and quintic beyond-Horndeski functions. This condition aligns the covariant degeneracy directions and permits a local disformal map to Horndeski when regular and invertible. For a finite, nonzero scalar kinetic term at the horizon, every nontrivial branch of the exact quadratic GLPV black hole is locally unstable or has a degenerate tensor cone near a simple outer horizon. Apart from identified exceptions, this obstruction extends to general shift- and reflection-symmetric quadratic GLPV theories and the regular Horndeski-related branch of the quartic-quintic class. Finally, for scalar-Gauss-Bonnet black holes with a vanishing horizon scalar kinetic term, we construct analytic power-law quartic beyond-Horndeski deformations whose associated quintic function is fixed by the same condition. At sufficiently small coupling, all local no-ghost and high-frequency gradient-stability conditions hold throughout the exterior. For a linear Gauss-Bonnet coupling, we estimate an interior scale below which the background and stability expansions lose perturbative control; this does not imply a physical instability.
↳ gr-qchep-phhep-th0 citations
45
Information geometry of non-equilibrium quantum states: Mixed metric structures on an extended information manifold
Kouji Kashiwa🇯🇵 · Hidefumi Matsuda🇨🇳
We discuss an information-geometric framework for characterizing quantum states in non-equilibrium dynamics. Using the transverse-field Ising chain model as a laboratory, we investigate the quantum Fisher information metric with particular emphasis on the mixed metric component $g_{h t}$ and related geometric observables, where $h$ is a controllable post-quench Hamiltonian parameter and $t$ is real time. The framework treats $h$ and $t$ as coordinates of an extended information manifold $(h, t)$ . The geometric observables characterize the speed of evolution on the manifold and the alignment between the temporal and parameter-deformation directions. Correlations between these geometric quantities and two widely used measures of non-equilibrium dynamics, the entanglement entropy and the Loschmidt echo, are analyzed.
↳ quant-phcond-mat.stat-mechhep-ph0 citations
46
QED nuclear medium effects at EicC
Oleksandr Tomalak🇨🇳
We evaluate quantum electrodynamics (QED) nuclear medium effects under experimental conditions at the future Electron-ion collider in China (EicC). We consider neutral-current and charged-current elastic scattering, as well as neutral-current and charged-current deep inelastic scattering. We compute cross-section corrections at first order in the opacity expansion and estimate kinematic modifications due to multiple rescattering within the nucleus. We perform the first calculations of charged-current deep inelastic scattering and polarized scattering. We present results for the anticipated $_{79}^{197} Au,_{82}^{208} Pb,$ and $_{92}^{238} U$ nuclei and extrapolate these calculations to the lighter $_{20}^{40} Ca$ isotope. We find that QED nuclear medium effects are non-negligible when extracting the process-independent non-perturbative structure of nucleons and nuclei at the EicC.
↳ nucl-thhep-exhep-phnucl-ex0 citations
47
Angular power spectrum of induced gravitational waves: breaking model and parameter degeneracies in PTA observations
Peng-Yu Wu🇨🇳 · Di Wu🇨🇳 · Jing-Zhi Zhou🇨🇳
Large primordial curvature and tensor perturbations on small scales can generate second-order tensor-scalar induced gravitational waves (TSIGWs) through scalar-scalar, tensor-scalar, and tensor-tensor source terms. TSIGWs are recognized as one of the principal contributors to the stochastic gravitational wave background (SGWB) observations. We explore the energy density spectrum of second-order TSIGWs in the presence of non-Gaussian primordial curvature perturbations. Furthermore, we present the first calculation of the anisotropic angular power spectrum associated with second-order TSIGWs, which provides a promising tool to discriminate them from other SGWB sources.
↳ astro-ph.COgr-qchep-phhep-th0 citations
48
Fundamental geometric limitations on disentangling nuclear-surface properties in relativistic heavy ion collisions
Hadi Mehrabpour🇨🇳 · Behnaz Behzadmoghaddam🇮🇷 · S. M. A. Tabatabaee Mehr🇮🇷 · Oscar Garcia-Montero🇪🇸 · Li Yan🇨🇳
The extraction of the nuclear surface diffuseness from relativistic heavy ion collisions is limited by the intertwined responses of geometry-driven observables to surface diffuseness and intrinsic nuclear deformation. We investigate this limitation using event-by-event Monte Carlo Glauber simulations, focusing on the sensitivity of multiparticle correlations to the Woods--Saxon surface diffuseness $a_{0}$ in intrinsically deformed nuclei. We systematically examine the local correlations between $a_{0}$ and quadrupole and octupole deformation parameters, $β_{2}$ and $β_{3}$ , and determine how these correlations affect the ability of different observables to constrain $a_{0}$ . We find that observables dominated by elliptic geometry exhibit a strong response to quadrupole deformation, leading to a local $a_{0}$ -- $β_{2}$ degeneracy that substantially limits their sensitivity to the nuclear surface diffuseness. Triangular correlations provide a more independent response to the nuclear surface and therefore retain additional information on $a_{0}$ , although their sensitivity can also be modified by intrinsic deformation. Extending the analysis to simultaneous quadrupole and octupole deformation shows that the local degeneracy and least-constrained directions depend on the nuclear configuration, demonstrating that the limitation on extracting $a_{0}$ is not described by a single global parameter correlation. We quantify these effects using multidimensional response maps, local sensitivity and information-geometric measures, and a Bayesian analysis of the resulting parameter constraints. The results clarify the fundamental limitations imposed by intrinsic multipole deformation on the determination of nuclear surface diffuseness from relativistic heavy ion collisions and identify multiparticle correlations that provide more independent information on $a_{0}$ .
↳ nucl-thhep-exhep-phnucl-ex0 citations

Affiliations

first authorsco-authorsvia INSPIRE