HEP Phenomenology·hep-ph

Tue·Jun 16, 2026Tuesday·June 16, 2026

65 papers—43 primary·22 cross-listed

01
JetParticle-JEPA: An Efficient Self-Supervised Representation Learning method for Jet Tagging in High-Energy Physics
Guillaume Letellier🇫🇷 · Antonin Vacheret🇫🇷 · Frédéric Jurie🇫🇷
Jet tagging at the Large Hadron Collider increasingly relies on deep learning models trained on massive simulated datasets, leading to high computational costs and limited robustness to detector mismodeling. We introduce JetParticle-JEPA (JP-JEPA), a self-supervised Joint-Embedding Predictive Architecture that learns physically meaningful jet representations directly from continuous particle clouds without tokenization or reconstruction of raw inputs. Built on a Particle Transformer backbone, JP-JEPA predicts latent representations of masked particles while preserving fine-grained kinematic correlations. On the JetClass benchmark, JP-JEPA achieves performance comparable to fully supervised state-of-the-art methods on the full dataset, surpasses supervised baselines in low-label regimes, and significantly outperforms existing SSL approaches. On Top Quark and Quark-Gluon Tagging benchmarks, it remains on par with supervised methods. The learned representations also exhibit strong robustness to missing detector information and improved uncertainty behavior, highlighting JP-JEPA as a promising foundation-model framework for robust and data-efficient jet physics at the LHC.
hep-phcs.AIcs.LG0 citations
02
Adiabatic response in the Migdal Effect
Stefan Nellen Mondragón🇦🇹 · Josef Pradler🇦🇹 · Mukul Sholapurkar🇦🇹
The Migdal effect-the prompt ionization induced by a sudden nuclear recoil-is widely used in direct dark matter searches, yet its validity beyond the impulse approximation has remained unresolved. We present the first first-principles calculation for isolated atoms, establishing the adiabatic crossover where ionization is suppressed. We show that this behavior is fully encoded in the scattering amplitude, without ad hoc assumptions, and map the relevant parameter space, finding that dark matter searches lie in the unsuppressed regime.
hep-phhep-ex2 citations
03
Event Generation with Parallel Langevin Sampling and Learned Stein Diagnostics
Rob Verheyen🇬🇧
Efficient event generation is a major computational challenge for precision collider phenomenology, especially for high-multiplicity final states where matrix-element evaluations are expensive and rejection-sampling efficiencies are low. We study an alternative approach based on many parallel underdamped Langevin chains, retaining one terminal state from each chain to obtain unweighted events while avoiding within-chain autocorrelation. A learned Stein discrepancy is used as a convergence diagnostic, providing a data-driven estimate of the relaxation time. We apply the method to tree-level $u u ˉ \to Z + n g$ event generation and find that relaxation requires only a modest number of exact-target Langevin steps, with mild growth over the multiplicities studied. Finally, we show that simple neural-network surrogate initialization can substantially reduce the required number of exact matrix-element and gradient evaluations.
hep-phstat.ML0 citations
04
Towards a consistent perturbation theory at finite temperature
Passant Ali🇩🇪 · Peter Lowdon🇩🇪 · Owe Philipsen🇩🇪
The standard approach to perturbation theory for finite-temperature quantum field theories has several issues, including the appearance of ill-defined on-shell contributions in the real-time formulation, and infrared diverges in massless theories. Earlier studies indicate that these issues all stem from the inconsistent thermal generalisation of the Gell-Mann-Low relation, which forms the foundation of perturbation theory in vacuum. This inconsistency arises from the use of free scattering states in the relation, which are known not to exist in interacting thermal theories. In this work, we propose a generalisation of the Gell-Mann-Low relation for scalar theories based on non-perturbative spectral insights, namely that finite-temperature scattering states can be described by damped but stable particle-like excitations, so-called thermoparticles. The perturbative expansion of this generalised relation gives rise to contributions with exactly the same topology as the standard finite-temperature approach, except that now the propagators appearing in this expansion are not those of a free field but of thermoparticles, which depend on the dynamics of the theory. We demonstrate that thermoparticle perturbation theory resolves the known problems of the standard approach. Furthermore, by comparing imaginary-time calculations at two-loop level with numerical lattice simulations of two-point correlation functions in massive $ϕ^{4}$ theory, we explicitly show that this framework gives rise to precise predictions, as in the vacuum case, in stark contrast to the standard approach.
hep-phhep-lathep-thnucl-th1 citation
05
Event generation for future DIS experiments
Peter Meinzinger🇨🇭 · Daniel Reichelt🇨🇭 · Federico Silvetti🇬🇧
In this contribution we discuss state-of-the-art hadron-level predictions for the deep-inelastic scattering process at next-to-leading-order precision for several multiplicities, consistently merged in one sample. We focus on the physics at (potential) future colliders, the Electron-Ion Collider planned at BNL as well as the higher energy experiments discussed as future options at CERN, a LHeC and a DIS phase of the Future Circular Collider dubbed FCC-eh.
hep-phhep-ex0 citations
06
Pre-Training for Simulation-Based Science: A Study on Jet Foundation Model Training Objectives
Ibrahim Elsharkawy🇨🇦 · Joschka Birk🇩🇪 · Vinicius Mikuni🇯🇵 · Wahid Bhimji🇺🇸 · Gregor Kasieczka🇩🇪 · Benjamin Nachman🇺🇸
Foundation models (FMs) trained on large datasets and fine-tuned on downstream tasks have emerged as a powerful paradigm in AI for science. Industrial FMs are typically trained using self-supervision with masking due to the lack of labels. In many scientific domains, accurate simulations are plentiful and facilitate large, labeled datasets. This opens up new possibilities for pre-training. We present a systematic comparison of pre-training methods using the OmniLearned High Energy Physics FM framework. We test supervised classification, flow-matching generation, and self-supervised masked particle modeling. All models are pre-trained on the JetClass dataset and fine-tuned on two representative downstream tasks, top jet classification and JetNet conditional generation. Among other observations, for classification tasks, we find that pure classifier pre-training is optimal when downstream labels and model capacity are plentiful, but combining it with self-supervised masked particle modeling (MPM) is uniquely powerful in the low-finetuning label regime. Flow matching-based generative pre-training seems to provide little benefit for downstream classification, and interestingly, for downstream generation, we find that flow matching must be in the pre-training objective to see a significant finetuning advantage, hinting at the orthogonality of classification and generation tasks. That is, for a model to transfer to both generative and classification downstream tasks, it must be pre-trained on both. This study provides a template for controlled scaling analysis of pre-training objectives for foundation models in simulation-based sciences.
hep-phcs.LG0 citations
07
The massless limit for massive amplitudes and the contraction of the little group
J. Lorenzo Díaz-Cruz🇲🇽 · Jonathan Reyes-Perez🇲🇽 · Jorge Leon Silverio🇲🇽
This paper is devoted to study the spin-spinor formalism to deal with amplitudes for massive particles. After presenting the basic formulae and conventions, we evaluate in detail the amplitudes for two specific examples, namely the decay W -> l \nu_l and the reaction e+ e- -> mu+ mu-. For each case, we display the amplitudes using charts that represent the flow of spin/helicities from the initial to the final particles, which can be used to calculate the total squared amplitude. One can also study the symmetries of the process by comparing different branches along the charts, which are related by those symmetries. Finally, we study the massless limit of the massive theory, employing the concept of Little Group Contraction (LGC), which was used first by Inonu and Wigner to derive the algebra of the Little Group (LG) for the massless case as the limit of the massive one.
hep-ph1 citation
08
$a_{0} (1450)$ -state twist-2 light-cone distribution amplitude moments within QCD sum rules and its implication in $B ˉ^{0} \to a_{0} (1450)^{+} ℓ^{-} ν ˉ_{ℓ}$ decays
Ya-Lin Song🇨🇳 · Yin-Long Yang🇨🇳 · Yan-Ting Yang🇨🇳 · Dong Huang🇨🇳 · Hai-Bing Fu🇨🇳 · Hai-Jiang Tian🇨🇳 · Dan-Dan Hu🇨🇳
Based on longstanding puzzle for the structure of light scalar meson, it is meaningful to make a deep research for its property in different decay processes especially in the bottom meson semileptonic decays. The current experimental and theoretical predictions are inclined to the quark-antiquark state in $B$ -decays, which is also the basic starting point of this work. Firstly, the first five-order $a_{0} (1450)$ -state leading-twist distribution amplitude $ξ$ -moments are calculated by using the QCD sum rule within background field theory, which all the gluon-condensate and quark-condensate are calculated up to full dimension-six accuracy. We present the their values up to nineth-order at initial scale. Then we construct $a_{0} (1450)$ -state twist-2 LCDA with light-cone harmonic oscillator models as the scenario 1 (S1), where the model parameters are determined by fitting the first five odd $ξ$ -moments using the least squares method. On the other hand, the truncated form of Gegenbauer polynomials expansion up to second-order is also considered as the scenario 2 (S2) to make a comparison, where the relationship between Gegenbauer moments and LCDA moments are considered. Subsequently, we calculated the $B ˉ^{0} \to a_{0} (1450)^{+}$ transition form factors (TFFs) by using the light-cone sum rules approach, incorporating contributions from both twist-2 and twist-3 LCDAs. By extrapolating TFFs to the entire physical $q^{2}$ -region with simplified series expansion, the differential decay width and branching ratios for the $B ˉ^{0} \to a_{0} (1450)^{+} ℓ^{-} ν ˉ_{ℓ}$ semileptonic decay are obtained. Finally, we present three angular observables including forward-backward asymmetry, lepton polarization asymmetry and $q^{2}$ -differential flat term.
hep-ph0 citations
09
Domain walls and magnetic monopoles in Grand Unified Models
Harish Hemming🇺🇸 · Tanmay Vachaspati🇺🇸 · Anja Wachowitz🇺🇸
Motivated by Grand Unification, we study the formation of magnetic monopoles in an SU(3) non-Abelian gauge theory. We find that the number density of magnetic monopoles depends critically on a parameter, $ϵ$ , that controls the abundance and subsequent decay of biased domain walls. For sufficiently small but non-vanishing values of $ϵ$ , very few monopoles and walls survive in our simulations, potentially solving the cosmological monopole over-abundance problem. In addition, the scenario predicts a stochastic gravitational background from biased domain walls and the possibility of magnetically charged black holes.
hep-phastro-ph.COhep-th1 citation
10
Causally connected regions in relativistic heavy ion collisions
Olivia Chabowski🇺🇸 · Joseph I. Kapusta🇺🇸
Quantifying causal connections within fireballs resulting from high energy nucleus-nucleus collisions is pertinent to assessing the viability of several proposed mechanisms that directly influence particle production and correlations. Fireball causal connections have previously been studied in the context of 1+1 dimensional Bjorken flow. We expand into 3+1 dimensions using Gubser flow, which includes transverse expansion. Our findings suggest that the volume of these causally connected fireballs are on the order of 10 to 100 fm $^{3}$ for observables dependent on the formation of the light quark condensates, but could be larger for other observables.
hep-ph0 citations
11
Exploring new physics in the angular distribution of $B ˉ \to D^{*} (\to D π) τ^{-} (\to V^{-} ν_{τ}) ν ˉ_{τ}$
Si-Yuan Liu🇨🇳 · Alakabha Datta🇺🇸 · Xian-Wei Kang🇨🇳
The decays $B ˉ \to D^{*} τ^{-} ν ˉ_{τ}$ provide sensitive probes of new physics in the $b \to c τ ν$ transition. We discuss the effects of new physics in the decay chain $B ˉ \to D^{*} (\to D π) τ^{-} (\to V^{-} ν_{τ}) ν ˉ_{τ}$ where $V$ is a vector meson. We first present a comprehensive analysis of the five-dimensional angular distribution for the full decay chain $B ˉ \to D^{*} (\to D π) τ^{-} (\to ρ^{-} ν_{τ}) ν ˉ_{τ}$ , exploiting the hadronic $τ$ decay to $ρ^{-} ν_{τ}$ to circumvent the experimental challenge of direct $τ$ reconstruction. The differential decay rate is expressed in terms of measurable kinematic variables $θ^{*}$ , $E_{ρ}$ , $θ_{ρ}$ , $χ_{ρ}$ , and $q^{2}$ -- with complete coefficient functions provided for scalar, pseudoscalar, vector, axialvector, and tensor new-physics interactions. From this distribution we construct a set of integrated observables, including the $D^{*}$ polarization fractions and lepton-side forward-backward and azimuthal asymmetries, which isolate distinct combinations of helicity amplitudes. We further perform a numerical analysis using current experimental data on $R_{D^{*}}$ and the $D^{*}$ longitudinal polarization fraction $⟨ F_{L}^{D^{*}} ⟩$ to constrain the complex new-physics couplings $g_{L}$ , $g_{R}$ , $g_{P}$ , and $g_{T}$ , revealing the correlations among them. Our formalism is also applicable to $τ \to a_{1} ν_{τ}$ , where the $3 π$ final states mainly come from the $a_{1}$ meson. The framework established here provides a powerful tool for disentangling new-physics scenarios with future high-statistics data.
hep-ph0 citations
12
Line-of-sight magnetic-field propagation effects on axion-like particle constraints from GRB 221009A
Chengcheng Han🇨🇳 · Zhanhong Lei🇨🇳 · Jiajie Yang🇨🇳 · Shutong Zhao🇨🇳
High-energy photons from GRB 221009A provide a powerful opportunity to probe axion-like particles (ALPs) through photon-ALP oscillations in cosmic magnetic fields. We revisit the ALP constraints implied by the LHAASO observation of this burst, with particular emphasis on the magnetic-field environments encountered along the line of sight. We include the host-galaxy, intergalactic, and Milky-Way magnetic fields and assess their respective impacts on the photon survival probability and on the exclusion limits in the ALP mass-coupling plane. We show that the constraints are only mildly affected by the choice of host-galaxy and Galactic magnetic-field models, but can change significantly once the intergalactic magnetic field is varied. Its field strength, coherence scale, and stochastic properties can all leave visible imprints on the derived exclusion contours, and in some cases generate pronounced oscillatory features. This demonstrates that the intergalactic magnetic field constitutes the dominant astrophysical uncertainty in extracting ALP limits from GRB 221009A. Our analysis highlights the importance of realistic propagation modeling in future gamma-ray searches for ALPs.
hep-phastro-ph.HE0 citations
13
Particle and Gravitational Wave Probes of Minimal Seesaw Neutrinos
Sanjoy Mandal🇰🇷 · Rishav Roshan🇬🇧 · Jose W. F. Valle🇪🇸
Observable gravitational waves (GWs) from first-order phase transitions (FOPTs) can coexist with distinct particle physics signatures. These include same-sign dilepton plus four~jet events at colliders, such as $e^{+} e^{-} / μ^{+} μ^{-} \to ℓ^{\pm} ℓ^{\pm} 4 j$ , neutrinoless double beta decay, as well as charged lepton flavor violating (cLFV) processes such as $μ \to e γ$ . We explore this synergy within the minimal low-scale linear seesaw model. This framework successfully reproduces neutrino oscillation data, providing a direct avenue to probe the neutrino mass ordering and Majorana nature at colliders. Crucially, the FOPT responsible for the GW background is driven by a leptophilic Higgs doublet, establishing a direct link between early-universe cosmology and terrestrial laboratory experiments.
hep-phastro-ph.CO0 citations
14
Constructing perfect spin-1 hydrodynamics from Boltzmann to Bose-Einstein statistics
Sudip Kumar Kar🇵🇱 · Valeriya Mykhaylova🇵🇱
We derive thermodynamic currents for a perfect fluid of massive spin-1 particles obeying Bose-Einstein statistics within the Wigner-function approach. Using a covariant spin density matrix, we construct spin-extended equilibrium distributions and obtain the energy-momentum and spin tensors that match, up to second order in polarization, those of spin-1/2 systems and the Boltzmann case. We find that the approach yields a unified description of relativistic spin hydrodynamics independent of statistics and spin representation. Furthermore, the framework fulfills the requirements of the divergence-type theory, with nonlinearly causal and stable dynamical equations.
hep-phhep-th0 citations
15
Pion radiative decays of excited hidden-charm pentaquark molecules: from $Σ_{c}^{(*)} D ˉ^{(*)} (2 S)$ molecules to the reported $P_{c}$ states
Yu-Jie Tang🇨🇳 · Wen-Yan Peng🇨🇳 · Rui Chen🇨🇳 · Fu-Lai Wang🇨🇳
The discovery of the hidden-charm pentaquarks $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$ by the LHCb Collaboration are very likely to identify as the $\Sigma_c^{(*)}\bar{D}^{(*)}$ molecules. A natural and crucial extension is the existence of excited molecular partners built from a ground-state charmed baryon and a radially excited anti-charmed meson, namely $\Sigma_c^{(*)}\bar{D}^{(*)}(2S)$ molecules. In a framework of chiral quark model, we systematic study pion-emission decays of such excited molecules into the known ground-state $P_c$ molecules. Our results show that the decay widths are sensitive to the spin structures and the coupled-channel interferences, i.e., the $\Sigma_c\bar{D}(2S)/\Sigma_c\bar{D}^*(2S)/\Sigma_c^*\bar{D}^*(2S)[1/2(1/2^-)]$ state decays to $P_c(4440)$ with a width of several MeV, while the width to $P_c(4457)$ is suppressed below $0.3$ MeV due to destructive interference. The pion-emission decay can be the key to unveiling the excited molecular spectrum of hidden-charm pentaquarks and provides decisive experimental signatures. We expect the future experiments such as the LHCb and PANDA can verify our predictions.
hep-ph0 citations
16
Production of high-orbital kaon excited states in the $K^{-} p$ reaction
Ting-Yan Li🇨🇳 · Zi-Yue Bai🇨🇳 · Xiang Liu🇨🇳
In this work, a systematic investigation of the production of high-orbital-excitation kaons in $K^{-} p$ reactions is carried out within an effective Lagrangian approach. The relevant $t$ -channel processes are constructed, and the model is calibrated using a single adjustable parameter determined from existing experimental data. With this parameter, the measured production cross sections for the $K_{3}^{*} (1780)$ , $K_{2} (1820)$ , $K_{2} (1770)$ and $K_{4}^{*} (2045)$ states are successfully reproduced. Employing the same framework, the production cross sections for other high-orbital kaons are predicted. The results indicate that these states possess sizable cross sections and exhibit characteristically forward-peaked angular distributions, which is a typical feature of $t$ -channel exchange, highlighting their great potential for observation in future experiments.
hep-phhep-exnucl-exnucl-thPRD(2026)·0 citations
17
Parton wakes and field angular momentum in chiral QCD plasma
Mohammad Yousuf Jamal🇨🇳
A fast parton moving through the quark-gluon plasma trails a wake of color fields, usually characterized through its screening cloud and the associated energy loss. Its behavior in a plasma carrying a chiral imbalance, set by a chiral chemical potential $μ_{5}$ , remains largely unexplored, in particular whether the imbalance induces a parity-odd component in the wake. We address this within chiral kinetic theory with Berry curvature corrections, at finite $μ_{5}$ and zero magnetic field. The screening sector is found to be nearly insensitive to $μ_{5}$ , which enters only through the Debye mass. The chiral imprint resides instead in a parity-odd sector, comprising an azimuthal field encircling the parton, a poloidal chromo-magnetic field, and a circulating color current. All three are linear in $μ_{5}$ and transverse to the velocity, and hence do no work on the parton. As the central result, these handed fields endow the wake with a net field angular momentum about the parton direction, odd in $μ_{5}$ and of order $1 0^{- 4}$ -- $1 0^{- 3} ℏ$ per parton. The chiral medium thereby opens a parity-odd channel connecting hard probes to the chiral and vortical structure of the plasma.
hep-ph1 citation
18
Why fluctuations of conserved charges in the confining regime above $T_{c h}$ behave as if the quarks were free?
L. Ya. Glozman🇦🇹
Some cumulants of the fluctuations of conserved charges soon above the chiral crossover behave as if the quarks were free. This was taken by many as evidence of deconfinement. At the same temperatures the mesonic correlators reveal the chiral spin and SU(4) symmetries, indicating that the propagating degrees of freedom are massless quarks connected into color singlets by the chromoelectric confining string. These correlators are qualitatively different from the free quark gas. Here we clarify the reason for the difference. The conserved quark number densities do not propagate in time but do propagate in spatial directions. The mesonic propagators calculated in full QCD differ radically from the free quark loop (quark gas) above T_ch. In contrast, the quark number density spatial propagator in full QCD at T > 220 MeV is very close to the free quark loop. In other words, the conserved charges do not see confinement, in contrast to the mesonic correlators. This is consistent with the well understood quark-hadron duality at T=0 in e^+e^- -> hadrons, where at invariant masses above 2 GeV the cross-section in the confining regime is represented by the free quark loop plus small perturbative corrections. All these features above T_ch but below the deconfinement temperature T_d can be combined within the following microscopic picture of the stringy fluid matter. It is a medium of the overlapping strongly interacting color singlet clusters. The quark interchanges between the clusters, required by Paili principle, make the quarks quasifree, which is reflected in fluctuations of conserved charges.
hep-phhep-exhep-lathep-th+12 citations
19
Rescuing flavor-symmetry-forbidden leptogenesis within the left-right symmetric framework
Yan Shao🇨🇳 · Zhen-hua Zhao🇨🇳
While the type-I seesaw model provides a unified framework for explaining the origin of neutrino masses and the baryon asymmetry of the Universe, flavor symmetries offer an attractive approach to understanding the observed neutrino mixing pattern. However, in many flavor-symmetry-based type-I seesaw models, either the Dirac neutrino mass matrix $M_{D}$ or the right-handed-neutrino mass matrix $M_{R}$ is constrained to be proportional to the identity matrix, which prevents the conventional leptogenesis mechanism from working. In this paper, without breaking the original flavor structure dictated by the employed flavor symmetries, we investigate whether such forbidden leptogenesis scenarios can be rescued within the framework of the left-right symmetric model. We show that, in these scenarios, the contribution of the Higgs triplet present in the left-right symmetric model to the CP asymmetries of right-handed neutrino decays can successfully reproduce the observed baryon asymmetry.
hep-ph0 citations
20
Towards the Detection of Thermal Solar Neutrinos
Carlos A. Argüelles🇺🇸 · Christopher V. Cappiello🇺🇸 · P. S. Bhupal Dev🇺🇸 · Pablo Figueroa🇪🇸 · Gonzalo Herrera🇺🇸 · Icarus Scoville🇺🇸
We show that $\sim$ keV thermal solar neutrinos, arising from electroweak processes in the solar plasma, are kinematically accessible to large-volume dark matter direct detection experiments via electron ionization signatures. Using S2-only data from the XENONnT experiment, we place an upper limit on the thermal solar neutrino flux of $η ≲ 1.2 \times 1 0^{8}$ times the standard model predicted value, while paired searches from XENONnT, LZ and PandaX give slightly weaker limits. The future XLZD experiment could improve these limits by orders of magnitude. While still far from a detection, this result establishes low-threshold direct detection experiments as a viable probe of the lowest-energy neutrino sources in astrophysics, with important implications for stellar physics and beyond.
hep-phastro-ph.COastro-ph.SR1 citation
21
Axiverse Strings Resolved
Rudin Petrossian-Byrne🇮🇹 · Giovanni Villadoro🇮🇹
Axiverse cosmic strings are resolved by non-perturbative string states with large tension. We show how, in some regions of moduli space, they dissolve into low-tension configurations that are fully captured by field-theoretic solitonic solutions, such as 't Hooft-Polyakov-like strings, allowing a post-inflationary cosmology within the original axiverse paradigm.
hep-phastro-ph.COhep-th2 citations
22
LIGO, LISA and Ultralight Axion-like Dark Matter
Lawrence M. Krauss🇺🇸
A coherent cosmic background of axion-like particles (ALPs) coupled to photons can produce a small periodic differential phase or polarization modulation for photons traversing separate arms in gravitational wave interferometers, peaked at a frequency associated with the particle mass, and suppressed whenever the dark-matter coherence length $λ_{coh}$ exceeds the arm length~ $L$ . For the LIGO audio frequency band the sensitivity to cosmic ALPs is below current bounds. For LISA, however, the natural mass range $m_{a} \sim 4 \times 1 0^{- 19}$ -- $4 \times 1 0^{- 16}$ ~eV -- corresponding to a sideband frequency in LISA's science band of $0.1$ ~mHz-- $0.1$ ~Hz -- may be observable. A 1-year shot-noise-limited search projects a sensitivity $g_{aγ γ} ≲ 5 \times 1 0^{- 14}$ ~GeV $^{- 1}$ across most of the band, reaching $\sim 7 \times 1 0^{- 15}$ ~GeV $^{- 1}$ near $0.1$ ~Hz, which is $1 0^{3}$ -- $1 0^{4}$ below the CAST helioscope bound. An RF heterodyne photodetection upgrade -- to either detector -- might extend the search sensitivity to $g_{aγ γ} \sim 6.5 \times 1 0^{- 14}$ ~GeV $^{- 1}$ at $m_{a} \sim 3 \times 1 0^{- 7}$ ~eV for LIGO and $g_{aγ γ} \sim 3.3 \times 1 0^{- 17}$ ~GeV $^{- 1}$ at $m_{a} \sim 5 \times 1 0^{- 13}$ ~eV for LISA. Dark-matter substructure can affect the signal in a several interesting ways.
hep-phastro-ph.CO0 citations
23
Massive right-handed neutrinos in $B ˉ \to D^{*} τ X ˉ$ decay
Nilakshi Das🇮🇳 · Alakabha Datta🇺🇸 · Tejhas Kapoor🇫🇷 · Danny Marfatia🇺🇸 · Lopamudra Mukherjee🇮🇳
We explore signatures of a massive right-handed neutrino (RHN) in angular distributions of $B ˉ \to D^{*} (\to D π) τ (\to π ν_{τ}) X ˉ$ decays, where $X$ is an invisible state. We assume the new physics is described by the standard model effective field theory extended with an RHN in the MeV-GeV mass range. We calculate for the first time the full differential distributions in terms of the visible final states, including the decay of the $τ$ lepton. We evaluate the sensitivity of various distributions to the new physics operators.
hep-phhep-ex1 citation
24
Dark Matter Attenuation inside the Earth: A Boltzmann Equation Approach
Chuan-Yang Xing🇨🇳 · Chen Xia🇨🇳
For strongly interacting or boosted dark matter, propagation through the Earth can involve sizable scattering and energy loss, reshaping the underground flux in energy, direction, and normalization. Scattered particles may still fall within the detector acceptance, so the detector-side signal depends on phase-space transport from the Earth's surface to the underground detector. In this work, we formulate this transport problem with the Boltzmann equation. Its integral solution organizes successive scattering effects as a deterministic expansion in scattering orders. We analyze the transport equation in flat-Earth and spherical-Earth geometries, and apply the method to Dirac dark matter with an isoscalar vector interaction. The iterative solution agrees well with the Monte Carlo spectrum.
hep-ph1 citation
25
Modular $S_{4}$ Scotogenic Model with Flavored Resonant Leptogenesis
Abhishek🇮🇳 · V. Suryanarayana Mummidi🇮🇳
We construct a radiative neutrino mass model that combines the scotogenic mechanism with modular $S_{4}$ flavour symmetry. The entire lepton flavour structure is governed by holomorphic modular forms of a single complex modulus $τ$ , eliminating the need for flavon fields. Beyond the Standard Model, the particle content consists of two right-handed Majorana fermions assigned to the $S_{4}$ doublet representation and an inert scalar doublet odd under a $Z_{2}$ parity. Neutrino masses emerge at one loop through the scotogenic mechanism, and the lightest $Z_{2}$ -odd state serves as a dark matter candidate. A comprehensive scan of the parameter space demonstrates consistency with all five neutrino oscillation observables at the $3 σ$ level. Having exactly two right-handed neutrinos forces the light neutrino mass matrix to rank two, leaving one neutrino massless and selecting normal ordering as the only viable option. The framework predicts a total neutrino mass in the narrow window $Σ m_{ν} ≃ 0.059$ -- $0.06 eV$ , well within current cosmological bounds, and an effective Majorana mass $m_{β β} ≃ (1.3$ -- $3.5) \times 1 0^{- 3} eV$ relevant for neutrinoless double beta decay searches. The modular structure of the right-handed Majorana mass matrix intrinsically produces a quasi-degenerate heavy neutrino spectrum, enabling flavoured resonant leptogenesis at $M_{1} \sim 1 0^{5} GeV$ without any fine-tuning. Integration of the full three-flavour Boltzmann equations confirms that the observed baryon asymmetry is reproduced, establishing that neutrino masses, leptonic mixing, and the baryon asymmetry of the Universe all find a common explanation within this framework.
hep-ph0 citations
26
Search for Invisibly Decaying Light Scalars at the FCC-ee
Aman Desai🇦🇺 · Tania Robens🇭🇷
We investigate the production of invisibly decaying light scalars in association with hadronically decaying $Z$ bosons at the Future Circular Collider-ee at a centre-of-mass energy $s = 240$ GeV. Several new physics models predict the existence of these low-mass scalar states, while the existing experimental constraints do not yet exclude these states. We study the low-mass scalar based on a simplified extension of the Standard Model, introducing an additional scalar singlet and a scalar dark matter candidate. The analysis is performed for a set of new scalars with mass in the range $(15, 120)$ GeV, by employing a selection-based strategy complemented with Multivariate Analysis techniques to discriminate the signal from background. The expected upper limits on the production cross-section times the branching fraction of the new scalars decaying invisibly are evaluated as a function of the scalar mass. We find that sensitivities of $\sim 1 0^{- 2}$ -- $1 0^{- 1}$ ~fb are achievable for scalar masses below the $Z$ boson mass, while sensitivities of $0.1$ -- $1$ ~fb are obtained in the mass range 80--120 \GeV. Depending on the mixing angle, novel scalars with masses up to 80 \GeV are within discovery reach.
hep-ph0 citations
27
Determining the Spin Density Matrix via Its Rank and Probing the Quantum Entanglement and Bell Non-Locality at the Lepton Colliders
Liwei Liu🇨🇳 · Xiqing Hao🇨🇳 · Dianwei Wang🇨🇳 · Lina Wu🇨🇳 · Tianjun Li🇨🇳
Considering two-fermion $F_{a} F_{b}$ productions and decays via one scalar or photon exchange at the $e^{+} e^{-}$ collider, we show that the rank $r_{ρ}$ of spin density matrix $ρ$ is equal to the number of degrees of freedom of the mediator. For one generic scalar exchange, the spin density matrix is rank one for a pure state. With rank-one condition, we can determine the spin analyzing powers for $F_{a}$ and $F_{b}$ and their product if the CP symmetry is violated and conserved, respectively, and probe the CP violation. These results can be applied to the $η_{c} \to Λ Λ ˉ$ at the BESIII experiment and the Higgs $\to τ τ$ at the LHC. For one photon exchange, the spin density matrix is rank two for a mixed state. Considering the $Λ Λ ˉ$ productions and decays at the BESIII experiment as an example, we show that the spin analyzing powers for $F_{a}$ and $F_{b}$ can be determined by the rank-two conditions in details. Therefore, we can reconstruct the spin density matrices, probe the quantum entanglement and Bell non-locality, and evade the no-go theorem. Furthermore, we conjecture that the $N \times N$ spin density matrix with $r_{ρ} \leq N - 2$ can be reconstructed at the lepton colliders in general.
hep-phhep-exhep-th3 citations
28
Static linear response of hot and dense QCD matter to electromagnetic fields: Leading hard and soft QCD corrections
Osvaldo Ferreira🇧🇷 · Eduardo S. Fraga🇧🇷 · Tyler Gorda🇺🇸 · Risto Paatelainen🇫🇮 · Leon Sandbote🇫🇮 · Kaapo Seppänen🇫🇮
We compute the static electromagnetic susceptibilities of a hot and dense quark-gluon plasma using perturbative Quantum Chromodynamics (QCD). Our evaluation includes the leading $O (α_{s})$ correction as well as the leading soft, resummed contribution of $O (α_{s}^{3/2})$ within electrostatic QCD. By matching to Lattice QCD at vanishing baryon chemical potential through Lattice perturbation theory, we establish a connection between perturbative results and Lattice simulations and assess the size of higher-order corrections. This extends the electromagnetic susceptibilities to finite baryon chemical potential, where Lattice methods are not applicable and establishes first-principle constraints on the quark-gluon plasma's electromagnetic response at temperatures and densities relevant for intermediate-energy heavy-ion collisions.
hep-phnucl-th0 citations
29
Chiral-odd structure of the $N \to Δ$ transition: tensor form factors from QCD light-cone sum rules
Ulaş Özdem🇹🇷
We present the first direct calculation of the tensor transition form factors (TFFs) of the $N \to Δ$ transition using the QCD light-cone sum rules. The matrix element of the tensor current sandwiched between the nucleon and $Δ$ states is parametrized in terms of four independent form factors, derived from Lorentz covariance, Hermiticity, parity, time-reversal, and the Rarita--Schwinger constraints. The natural-parity character of the $1/ 2^{+} \to 3/ 2^{+}$ channel combined with the spin- $1$ polarization content of the Rarita--Schwinger spinor imposes a trailing $γ_{5}$ in the parametrization, in analogy with the gravitational $N \to Δ$ case. Using the nucleon distribution amplitudes expanded in wavefunctions of different twists, we compute the four TFFs in the spacelike range $1 \leq Q^{2} \leq 10$ ~GeV $^{2}$ for two sets of light-cone input parameters, and extrapolate to the static limit through multipole fit functions. A flavor decomposition into $u$ - and $d$ -quark contributions reveals three qualitatively distinct patterns among the four TFFs: $d$ -quark dominance with $∣ F^{d} ∣ ≫ ∣ F^{u} ∣$ for $F_{1}$ and $F_{2}$ -- in marked contrast to the diagonal nucleon tensor charges where the $u$ -quark dominates; an antisymmetric flavor structure $F^{u} \approx - F^{d}$ for $F_{3}$ , which naturally explains the absence of a stable isoscalar sum rule for this form factor; and comparable but opposite-sign flavor contributions to $F_{4}$ , with a suppressed isoscalar combination. The TFFs provide chiral-odd information complementary to the electromagnetic and gravitational $N \to Δ$ transitions and offer model-independent input for future analyses of transversity-related transition observables, to be checked against lattice QCD and other phenomenological approaches.
hep-phhep-exhep-lat0 citations
30
Sommerfeld Enhancement in Spin-1 Electroweak Dark Matter
Tomohiro Abe🇯🇵 · Motoko Fujiwara🇯🇵 · Junji Hisano🇯🇵
We study a renormalizable spin-1 electroweakly interacting dark matter (DM) model in which the DM particle is the neutral component of a $Z_{2}$ -odd $SU (2)_{L}$ triplet vector boson. The model predicts an additional $Z_{2}$ -even heavy vector triplet, $W^{' \pm}$ and $Z^{'}$ , which is generically heavier than the DM particle and whose mass is closely related to the DM mass. Taking into account the Sommerfeld enhancement due to long-range electroweak interactions, we evaluate the thermal relic abundance of the spin-1 DM. We find that the observed relic abundance is reproduced through the freeze-out mechanism for DM masses ( $m_{V}$ ) in the range $3.6 TeV ≲ m_{V} ≲ 9.2 TeV$ within a perturbative regime. A heavier DM mass is favored when the heavy vector boson mass approaches the DM mass, since annihilation processes into a heavy vector boson and a Standard Model particle significantly enhance the effective annihilation cross section. This behavior is distinctive from spin-0 and spin- $1/2$ electroweak DM scenarios, which typically predict a DM mass around $3 TeV$ . We further investigate indirect detection prospects and find that the Cherenkov Telescope Array Observatory (CTAO) will probe the entire viable parameter region. In particular, for $m_{V} ≳ 7.5 TeV$ , the model predicts a characteristic double-peak gamma-ray signature: one peak arising from the unresolved $γ γ$ and $Z γ$ channels, and the other from the $Z^{'} γ$ annihilation channel.
hep-ph1 citation
31
High-quality Axion Strings from Monopole Strings
Nathaniel Craig🇺🇸 · Amalia Madden🇺🇸
Five-dimensional 't Hooft-Polyakov monopole strings whose cores restore a non-abelian gauge symmetry become axion strings for extra-dimensional axions. The parametric separation between the string tension and the scale of quantum gravity admits a viable post-inflationary cosmology for high-quality axion dark matter.
hep-phhep-th2 citations
32
Light-front diagnostics in the 't Hooft model: I. Wave functions, EMT decomposition, and the diagonal GPD overlap
Arkadiy I. Syamtomov🇺🇦
I examine how the longitudinal light-front wave function of a meson encodes forward energy-momentum tensor (EMT) structure and the diagonal part of an off-forward generalized parton distribution in the large- $N_{c}$ 't~Hooft model. Light-light, equal-mass reference, heavy-light, and heavy-heavy systems are compared through their momentum distributions, differential entropy, bilocal Coulomb kernel, and forward mass-squared decomposition. An independent sine-basis calculation confirms the light-light spectrum despite the slow convergence of the sine representation. For equal constituent masses, the second moment obtained from the exact diagonal overlap has no term linear in the asymmetric skewness variable $b$ , while its regular $b^{2}$ and $b^{3}$ coefficients are equal and determined by a universal kinematic contribution and a weighted wave-function gradient norm. At the equal-mass reference point, corresponding to $β = 1/2$ , the boundary expansion becomes resonant and generates a $b^{4} ln^{2} (1/ b)$ nonanalyticity, identifying the precise limitation of the diagonal two-body overlap. The companion Part II analysis constructs the ERBL completion required to cancel this support-dependent nonanalyticity and restore the analyticity of the local EMT moment.
hep-ph1 citation
33
A Minimal Dark $U (1)_{D}$ Framework for Inverse Seesaw Neutrino Masses and Dark Matter
D. T. Huong🇻🇳 · N. T. Duy🇻🇳 · Phung Van Dong🇻🇳
We propose a minimal framework based on a dark $U (1)_{D}$ gauge symmetry that simultaneously accounts for neutrino masses and dark matter within an inverse seesaw realization. In this setup, the smallness of light neutrino masses is controlled, suppressed by a lepton-number violating parameter $μ$ , which arises dynamically by dark field corrections rather than being introduced by hand. The limit $μ \to 0$ restores lepton number symmetry, ensuring its, thus neutrino mass, smallness in the sense of 't Hooft naturalness. We analyze the neutrino mass matrix and active-sterile mixing, highlighting their impact on non-unitarity and charged lepton flavor violation. The model is consistent with current experimental constraints while allowing potentially observable signals, such as $μ \to e γ$ . The dark $U (1)_{D}$ symmetry stabilizes the dark matter candidate and links the neutrino and dark sectors. Viable parameter regions satisfying dark matter relic density, direct detection, and collider bounds are identified. This framework provides a minimal and predictive realization of neutrino mass generation and dark matter stability with a naturally small $μ$ parameter.
hep-ph1 citation
34
Diffractive structure functions from JIMWLK evolution
Tuomas Lappi🇫🇮 · Heikki Mäntysaari🇫🇮 · Pyry Runko
We compute diffractive structure functions from Wilson line configurations whose energy evolution is given by the JIMWLK equation. We use a JIMWLK evolution setup that has already been constrained with exclusive vector meson production data from HERA. We compare our results to HERA measurements and also extended to heavy nuclei. In particular we can calculate predictions for the nuclear modification factor and diffractive-to-total cross section ratios at the EIC.
hep-phnucl-th0 citations
35
Revealing the nature of double-strangeness pentaquark states via femtoscopic correlation functions
Zheng-Ting Lai🇨🇳 · Jun-Xu Lu🇨🇳 · Zhi-Wei Liu🇨🇳 · A. Martinez Torres🇧🇷 · K. P. Khemchandani🇧🇷 · Li-Sheng Geng🇨🇳
Recent discoveries of exotic hadrons, which cannot be classified within the conventional quark model of $q q ˉ$ mesons and $q q q$ baryons, strongly imply the existence of dynamically generated hadronic molecules. Some of these hadron-hadron interactions are accompanied by coupled-channel effects, which remain challenging to quantitatively determine. In this work, we demonstrate that femtoscopy provides a sensitive probe of such coupled-channel dynamics. We calculate correlation functions for the double-strangeness pentaquark candidates $P_{css} (4493)$ ( $J^{P} = 1/ 2^{-}$ ) and $P_{css} (4633)$ ( $J^{P} = 1/ 2^{-}$ or $3/ 2^{-}$ ), revealing clear signatures of the attractive interactions that can form bound states. The results are markedly different from those obtained in scenarios that neglect off-diagonal transitions, highlighting the importance of coupled-channel effects for understanding the structure of these hadrons.
hep-ph1 citation
36
Modern Determination of Pion and Kaon Fragmentation Functions from SIA and High-Precision COMPASS SIDIS Multiplicities
HAPS Collaboration · Maryam Soleymaninia · Hamzeh Khanpour · Hubert Spiesberger · Majid Azizi · Michael Klasen · Hadi Hashamipour
We present a combined determination of charged-pion and charged-kaon fragmentation functions (FFs), denoted HAPS-PiFF1.0 and HAPS-KaFF1.0, at next-to-leading order (NLO) and within a next-to-next-to-leading-order (NNLO) perturbative QCD setup. The analysis combines single-inclusive electron-positron annihilation (SIA) data with charge-separated semi-inclusive deep-inelastic-scattering (SIDIS) multiplicities from HERMES and COMPASS. A central goal of this work is to incorporate the modern COMPASS SIDIS input, namely the COMPASS 2025 proton-target multiplicities and the COMPASS 2026 revised isoscalar-target multiplicities, into a common charged-pion and charged-kaon FF analysis and to assess their role in the resulting flavor separation. The revised isoscalar data supersede the earlier COMPASS measurements used in previous global fits. The charge-separated pion multiplicities provide important constraints on favored and unfavored light-quark fragmentation, while the kaon measurements enhance the sensitivity to light-quark, unfavored, and strange-to-kaon fragmentation channels. In both analyses, the gluon FF remains indirectly constrained in the present SIA+SIDIS framework and should be interpreted with appropriate caution. The extractions are carried out using the publicly available MontBlanc framework, and the resulting HAPS-PiFF1.0 and HAPS-KaFF1.0 replica sets are provided in the standard LHAPDF format.
hep-phhep-ex0 citations
37
QCD-like theories at next-to-next-to-leading order with $N_{F} = 2$ non-degenerate fermions
Johan Bijnens🇸🇪 · Daniil Krichevskiy🇳🇴
QCD-like theories with $N_{F} = 2$ fermion flavours in real and pseudoreal representations are studied within Chiral Perturbation Theory. For the pseudoreal symmetry-breaking pattern $S U (4) / S p (4)$ , the reduced NLO Lagrangian is derived. The NLO and NNLO corrections to the pion masses, decay constants, and vacuum condensates are calculated for non-degenerate fermion masses, extending previous results obtained for degenerate masses and for the non-degenerate case at NLO. Using the available spectroscopic and scattering lattice data for the $S p (N_{c} = 4)$ gauge theory with two fermion flavours, fits of the NLO low-energy constants are performed at NNLO precision. It is found that higher-order corrections are important for reproducing lattice observables and have a significant impact on the phenomenology of strongly interacting pionic dark matter, particularly in the regime of big $M_{π} / F_{π}$ .
hep-phhep-lat0 citations
38
Spin-Selective Hadron Spectroscopy via Azimuthal Anisotropies from Entanglement-Enabled Spin Interference
Samuel Corey🇺🇸 · James Daniel Brandenburg🇺🇸
The $π^{+} π^{-}$ invariant mass spectrum above the $ρ^{0} (770)$ is rich with broad, overlapping resonances. Disentangling them, whether in photoproduction, ultra-peripheral heavy-ion collisions, or electroproduction, is a longstanding challenge for conventional partial-wave analysis. We show that the recently observed entanglement-enabled spin-interference effect in ultra-peripheral collisions provides a quantum-mechanical filter that resolves this ambiguity: the angular harmonics $A_{n}$ of the $cos (n Δ ϕ)$ asymmetry, which are governed by selection rules in the spin of the interfering states. Specifically, overlap between two distinct spin-1 amplitudes leads to interference that populate $A_{2}$ alone, while overlap of a spin-1 amplitude with a spin-2 one generates $A_{1}$ and $A_{3}$ . Utilizing ALICE data in the $1.0$ -- $1.4 GeV c^{- 2}$ region, we demonstrate that two physically distinct hypotheses -- an additional spin-1 $ρ^{'} (1450)$ (produced via photonuclear interactions) versus a spin-2 (photon-photon) $f_{2} (1270)$ state -- fit the invariant mass spectrum equally well but predict different $A_{n}$ : identically zero $A_{1}$ and $A_{3}$ in the spin-1 case, versus pronounced peaks in the spin-2 case. This selection rule provides a new tool for hadronic spectroscopy in ultra-peripheral collisions and the first viable route to isolating the $γ γ \to π^{+} π^{-}$ continuum from the dominant photonuclear background, revealing a clean low-energy probe of non-perturbative QCD.
hep-phnucl-exnucl-th0 citations
39
Threshold cusp effects to measure masses of radiatively decaying hadrons: The $B_{s 0}^{*}$ mass from the $Υ ϕ$ spectrum
Hai-Long Fu🇩🇪 · Xu Zhang🇨🇳 · Feng-Kun Guo🇨🇳 · Christoph Hanhart🇩🇪 · Ulf-G. Meißner🇩🇪 · Mao-Jun Yan🇨🇳
Hadrons that decay predominantly into final states containing photons are notoriously difficult to detect at hadron colliders. Prominent examples are the yet-unobserved $B_{s 0}^{*}$ and $B_{s 1}$ , the bottom partners of the $D_{s 0}^{*} (2317)$ and $D_{s 1} (2460)$ , which are expected to exhibit exotic properties deviating from the conventional quark-model predictions of $b ˉ s$ mesons. We propose a general, model-independent method to overcome this problem: when the target hadron has an attractive $S$ -wave interaction with a companion hadron of precisely known mass, the line shape of a suitable final state develops a cusp at the pair threshold, or a peak just below it if the attraction binds, so that subtracting the companion mass returns the target mass, up to the binding energy in the latter case. As a proof of concept, a leading-order particle-dimer calculation of the $D D ˉ_{s} K$ three-body system reproduces the $X (4274)$ structure in the LHCb $J / ψ ϕ$ distribution extracted from $B \to K J / ψ ϕ$ , as a $D_{s 0}^{*} D ˉ_{s}$ threshold cusp driven by a nearby virtual-state pole, yielding $m_{D_{s 0}^{*}} = (2322 \pm 6)$ MeV in agreement with its measured value and favoring $J^{P C} = 0^{-+}$ for the $X (4274)$ . Transferring the elastic three-body interaction to the bottom sector, we predict an analogous structure at the $B_{s 0}^{*} B ˉ_{s}$ threshold near $11.09$ GeV, making the $Υ ϕ$ invariant-mass distribution at the LHC a clean probe of the $B_{s 0}^{*}$ mass.
hep-phhep-ex1 citation
40
Hadronic tensor in lattice gauge theories by quantum computing
Dairui Zou🇨🇳 · Tianyin Li🇯🇵 · Jian Liang🇨🇳 · Enke Wang🇨🇳 · Hongxi Xing🇨🇳
The hadronic tensor encodes crucial information regarding the internal structure of hadrons, reflecting the non-perturbative features of quantum chromodynamics (QCD). In this work, we directly compute the hadronic tensor within (1+1)-dimensional $U (1)$ and $SU (2)$ gauge theories by evaluating real-time current-current correlation functions. Utilizing quantum algorithms executed on classical hardware, we demonstrate that the hadron form factors for both meson and baryon states can be reliably extracted from the hadronic tensor. Our methodology is validated by strong agreement with both direct calculation and exact diagonalization of the form factors.
hep-phhep-latnucl-th2 citations
41
Scalar $D^{(*)} K^{(*)}$ and $D^{(*)} π (ρ)$ molecular states from B meson decays
Jing-Rui Shi🇨🇳 · Jiang-Tao Zhang🇨🇳 · Ye Xing🇨🇳
In this paper, we investigate the production of scalar singly charmed four-quark states from $B$ meson decays, employing phenomenological SU(3) flavor symmetry analysis and final-state interaction theory. Our study focuses on their production branching ratios and $C P$ violation. The results show that the branching ratios for producing either $V V$ or $P P$ molecular states from $B$ meson decays can be as large as the order of $1 0^{- 4}$ . Moreover, for processes with direct $C P$ violation, the production of $V V$ molecular states exhibits a sizable $C P$ asymmetry of order $1 0^{- 3}$ . Our findings also suggest that the recently observed $T_{c ˉ s ˉ 0}^{*} (2870)^{0}$ state is more consistent with the $D^{* 0} K^{* 0}$ molecular configuration. We expect that our predictions will be validated by future experiments.
hep-ph0 citations
42
A scaling non-compact QCD axion
Georgios K. Karananas🇩🇪 · Mikhail Shaposhnikov🇨🇭
We present a dynamical mechanism for the erasure of inflationary isocurvature perturbations of the non-compact QCD axion. The key ingredient is an early-time runaway exponential potential, which drives the axion onto the well-known scaling cosmological attractor after inflation. Once on the attractor, the axion tracks the dominant component of the Universe, radiation, and isocurvature modes are erased even if the field is effectively massless during inflation. When the QCD potential turns on, the axion carries nonzero velocity, and kinetic misalignment can become operative. The exponential potential induces residual CP violation, potentially accessible to future electric dipole moment searches. This mechanism requires that the axion be effectively non-compact over the field range relevant for its post-inflationary evolution.
hep-phgr-qchep-th0 citations
43
First Experimental Limit on the Thermal Solar Neutrino Flux
Cecilia Ferrari🇺🇸 · Gonzalo Herrera🇺🇸 · Brooke Russell🇺🇸
The neutrino sky below 165\,keV is yet to be explored. This region provides a unique probe of stellar cooling mechanisms through the detection of thermal solar neutrinos and the low-energy tail of the $pp$ solar cycle. Here, we investigate prospects for probing this regime via neutrino capture on tritium. Analyzing KATRIN public data, we set the first experimental bound on the thermal solar neutrino flux $Φ/ Φ_{SSM} < 1.86 \times 1 0^{18}$ at 95\%~CL ( $1.58 \times 1 0^{18}$ at 90\%~CL), and show that a $100 kg \cdot yr$ exposure would constrain the thermal solar neutrino component to $Φ/ Φ_{SSM} ≲ 1 0^{4}$ and detect the low-energy $pp$ flux at the Standard Solar Model (SSM) level. Neutrino--electron elastic scattering from $pp$ cycle neutrinos are identified as an irreducible background for neutrino capture searches.
hep-phhep-exnucl-ex1 citation
44
Cosmological Dynamics of the Thermal Scalar Near the Hagedorn Temperature
Arnab Pradhan🇨🇦 · Luis Rufino🇺🇸 · Scott Watson🇺🇸
We study the cosmological dynamics of the thermal scalar the winding string mode that becomes massless at the Hagedorn transition by coupling it to the string-frame gravi dilaton effective action. This provides a field-theoretic framework for investigating winding mode dynamics near the Hagedorn temperature and their role in string cosmology. Below the Hagedorn temperature, the phase space contains static configurations in which the thermal scalar balances the shifted dilaton evolution. These configurations are boundary states rather than attractors, and when the thermal scalar mass depends on the scale factor, winding mode back reaction opposes expansion and can reverse it. Above the Hagedorn temperature, the tachyonic thermal scalar generates negative effective energy density while preserving the null energy condition, enabling branch changes of the Brustein Veneziano type. These transitions do not provide the graceful exit required to connect the Hagedorn phase to standard cosmological evolution. At the Hagedorn temperature itself, the quadratic effective theory breaks down and higher order interactions become essential. Because the thermal scalar originates as a Euclidean order parameter, our Lorentzian treatment should be viewed as an effective dynamical model of the Hagedorn transition. Within this framework, the thermal scalar clarifies the dynamical structure surrounding the Hagedorn transition and shows how the Hagedorn exit problem cannot be resolved within the quadratic effective theory alone.
↳ hep-thastro-ph.COhep-ph0 citations
45
A Supernova Constraint on F-theory
Sebastian Vander Ploeg Fallon🇺🇸 · James Halverson🇺🇸 · Liam McAllister🇺🇸 · David J. E. Marsh🇬🇧
We study constraints on the quantum chromodynamics (QCD) axion in F-theory, a strongly coupled limit of string theory. We build models of QCD from compactifications to four dimensions on elliptic fibrations over toric threefolds $B_{3}$ , characterized by an integer $N = h^{1, 1} (B_{3})$ . The QCD axion mass increases with $N$ , and we find that models with sufficiently high $N$ are inconsistent with observations of the neutrino burst from supernova 1987A, disfavoring large regions of the moduli space. Specifically, at least $95%$ of models with $N \geq 8, 791$ -- a regime that arguably contains the vast majority of known F-theory topologies -- have a QCD axion mass $m_{QC D} > 15 m e V$ and are thus constrained. This limit is independent of cosmology. We only consider weakly-curved threefolds, where $α^{'}$ corrections are plausibly negligible.
↳ hep-thastro-ph.COhep-ph0 citations
46
Experimental exploration of the QCD phase diagram
A. Andronic🇩🇪 · P. Braun-Munzinger🇩🇪 · K. Redlich🇵🇱 · J. Stachel🇩🇪
The different phases of strongly interacting matter are governed by Quantum Chromodynamics (QCD). At high temperature and/or density a deconfined, chirally symmetric phase of quarks and gluons is expected to govern the nature of strongly interacting matter, the so-called quark-gluon plasma. Here we review what is known about the existence of this exotic form of matter from an experimental point of view and confront the results with QCD predictions based on 'Lattice QCD', where QCD is discretized on a space-time lattice and solved numerically in a Monte Carlo approach. The form of the presentation is explicitly pedagogical but the results include even very recent developments. Our research is based on the interpretation of hadron production data from relativistic nucleus--nucleus collisions over a wide energy range, with the aim to make progress in the understanding of the QCD phase, and of phenomena like deconfinement and hadronization.
↳ nucl-exhep-phnucl-th0 citations
47
Centaurus A Inner Lobes -- I. Hydrodynamic modeling of a Precessing Jet
Rita C. Anjos🇧🇷 · Brian Reville
We present a numerical investigation into the precessing jets of the inner lobes of Centaurus A, focusing on their dynamical evolution and interaction with the surrounding medium. Using three-dimensional relativistic hydrodynamic simulations, we model the development of large-scale jet and lobe structures driven by precession. Our setup incorporates physically motivated parameters to reproduce observed morphological features. We compare the resulting structures from our simulations with observed radio images of Centaurus A, particularly focusing on the S-shaped morphology, the distribution of bright emission regions, and the observed asymmetry between the northern and southern lobes. Our findings indicate a precession period of 1.8 Myr, which reproduces observational characteristics. This study explores the role of jet precession in shaping the inner lobes of Centaurus A.
↳ astro-ph.HEhep-phMNRAS(2026)·0 citations
48
Probing the fate of large primordial perturbations with exoplanets
Théo Paré🇫🇷 · Julien Lavalle🇫🇷
We propose ultra-wide-orbit exoplanets as a novel probe of small-scale dark matter objects. These systems are highly sensitive to gravitational perturbations that could be induced by a Galactic population of compact baryon-free dark matter objects -- whether point-like or extended. Focusing on ultra-compact minihalos, which may arise from large primordial perturbations deviating from the canonical scale-invariant power spectrum, we derive new constraints on their injection scale and amplitude. These constraints complement existing dynamical limits and are expected to improve with upcoming exoplanet surveys. Furthermore, the detection of additional loosely bound exoplanets with these surveys could significantly tighten these constraints. Beyond constraints, we also identify characteristic observational signatures in these systems that could help trace a population of dark matter objects. All this strengthens the potential of exoplanetary science to probe the dark universe back to its very primordial properties.
↳ astro-ph.COastro-ph.EPastro-ph.GAhep-ph1 citation
49
A Multimessenger Analysis of the High-Energy Milky Way: Source Populations Contribute Significantly to IceCube's Galactic Neutrino Flux
Alisha Roberts🇺🇸 · Ilias Cholis🇺🇸 · Dan Hooper🇺🇸 · Samyak Jain🇺🇸
We perform a joint analysis of the high-energy neutrino emission observed from the Galactic Plane by IceCube and the diffuse ultra-high-energy gamma-ray emission measured by LHAASO. We compare this data to models that include diffuse emission from cosmic-ray interactions in the interstellar medium, unresolved TeV halos, and unresolved Galactic neutrino sources. We find that the gamma-ray emission can be explained by a combination of diffuse processes and unresolved TeV halos. The observed neutrino emission cannot be generated by cosmic-ray interactions in the interstellar medium alone, but requires contributions from one or more unresolved source populations. Across a wide range of assumptions about Galactic cosmic-ray transport, we find that Galactic neutrino sources contribute significantly to the neutrino flux observed from the Galactic Plane and are likely responsible for most of this emission.
↳ astro-ph.HEastro-ph.GAhep-ph0 citations
50
The limits of lattice inflation: a cautionary tale
Will Barker🇨🇿 · Benjamin Gladwyn🇬🇧 · Sebastian Zell🇩🇪
Cosmological lattice simulations have become important tools for studying non-perturbative dynamics in the early Universe. Many widely used codes, however, approximate the gravitational background by an exact Friedmann-Lemaître-Robertson-Walker (FLRW) spacetime and neglect metric perturbations. We show that, during inflation, this approximation prevents the freezing of superhorizon modes. During slow roll, the curvature power spectrum decays as $H^{4}$ , while the deviation becomes substantially stronger during ultra-slow roll. As a result, inflationary observables can be significantly distorted. In contrast, reheating studies appear to be considerably less sensitive to the omission of metric perturbations. We propose a practical criterion for assessing the validity of FLRW simulations based on the inclusion of first-order metric perturbations, and implement it in CosmoLattice.
↳ astro-ph.COgr-qchep-phhep-th1 citation
51
Tidal Stripping of Matter Bound to the Secondary in Extreme Mass-Ratio Inspirals
Sreejith Nair🇮🇳 · Sayak Datta🇮🇹
Environmental studies of extreme mass-ratio inspirals (EMRIs) have focused almost entirely on matter surrounding the primary supermassive black hole. We instead consider matter bound to the stellar-mass secondary (e.g., gas or dark matter); which can be progressively tidally stripped during the LISA-band inspiral. This changes the bound mass of the inspiraling object, modifying the gravitational-wave (GW) phase at leading order in the secondary mass. Furthermore, as the signal interpolates from an initially dressed inspiral to a nearly bare one, it can produce a characteristic inflection in the residual phase with constant mass waveform templates. Even for an environmental mass $\sim 1 0^{- 3} M_{⊙}$ , the cumulative dephasing relative to in band initial bound mass waveform can be larger than unity. In subsolar mass cases, the relative dephasing can reach $O (1 0^{3}) rad$ . Neglecting this effect may bias inferred EMRI parameters at the level of the fractional change in the in-band bound mass. The tidal stripping phenomena carry information about the mass and the compactness of the bound matter, enabling probes of sub-AU, planetary- to subsolar-mass environments surrounding stellar-mass black holes.
↳ gr-qcastro-ph.HEhep-exhep-ph0 citations
52
Mapping Domain-Wall Bayesian Reconstruction with LISA
Satyabrata Datta🇨🇳 · Rome Samanta🇮🇹
We study the Bayesian reconstruction of peaked domain-wall gravitational-wave signals at LISA and construct reconstruction maps over the signal-parameter plane. These maps identify the regions in which the signal can be probed with minimal posterior uncertainty and parameter degeneracy. Our analysis employs a two-parameter domain-wall spectral template and includes isotropic, unmodulated astrophysical foregrounds from Galactic double white-dwarf binaries and extra-galactic compact binaries, together with LISA instrumental noise. The inference is performed for 64 injection points distributed on an equidistant grid using nested sampling, and the resulting posterior quantities are interpolated with the Clough--Tocher method to generate smooth maps over the full parameter plane. We find that LISA reconstructs domain-wall signals most effectively when the annihilation temperature lies approximately in the range $1 0^{3} - 1 0^{6} GeV$ . In this regime, the posterior becomes both tighter and less degenerate, enabling genuine two-parameter reconstruction. The most favorable region corresponds to signals with $SNR ≳ 50$ , while signals with $SNR \sim 10$ can still be reconstructed effectively only in a narrower part of parameter space concentrated near $T_{*} ≲ 1 0^{5} GeV$ . In terms of the observable spectrum, this weaker-signal region corresponds approximately to peak amplitudes $Ω_{GW}^{peak} h^{2} ≳ 4 \times 1 0^{- 11}$ and peak frequencies typically satisfying $f_{p} ≲ 10 - 20 mHz$ . Our results provide a quantitative reconstruction forecast for peaked domain-wall signals in the LISA band and a useful guide for particle-physics realizations of domain walls that predict peaked gravitational-wave spectra in the milli-Hz range.
↳ astro-ph.HEastro-ph.COgr-qchep-ph3 citations
53
Consistency between X-ray and UV-Optical reverberation measurements in NGC 5548
Amit Kumar Mandal🇵🇱 · Bożena Czerny🇵🇱 · Michal Dovčiak🇨🇿 · Elias Kammoun · Iossif Papadakis
The hard X-ray $-$ emitting hot corona is a key component of active galaxies. Constraints on the hot corona height can be derived from reverberation studies in both the X-ray and optical bands. X-ray reverberation (X-ray $-$ RM) studies often imply a very low corona height, whereas UV/optical reverberation mapping (photometrcic continuum $-$ RM) typically points to a much larger one. To reconcile this discrepancy, we examine the constraints provided by both methods for the same source. We adopt a uniform methodology using the {\tt KYNSED} and {\tt KYNXiltr} codes within a consistent modeling framework for reverberation mapping, applicable across both the X-ray and UV-optical spectral and time domains. We select the source NGC 5548, for which the necessary observational data are available in the literature. We carry out our analysis for NGC 5548, a source with extensive reverberation mapping data obtained independently in the X-ray and UV-optical bands across different epochs. Our results hint for a substantial discrepancy between the global parameters required to reproduce the X-ray and those needed to fit the UV-optical reverberation signals. In particular, the mismatch in the inferred black hole mass and accretion rate presents a significant challenge for interpreting the observed time delays within a unified reflection-based framework. Our unified reflection-based modeling sheds light on X-ray and UV-optical variability of NGC 5548, but discrepancies in black hole mass, accretion rate, and corona properties might imply fundamental challenges to a self-consistent model. However, future analyses leveraging extended X-ray dataset with improved treatment of absorption and variability coherence are crucial to obtaining more robust constraints.
↳ astro-ph.GAastro-ph.COastro-ph.HEhep-phAstron.Astrophys.(2026)·0 citations
54
Strong primordial inhomogeneities of axion-like field in Einstein-Gauss-Bonnet gravity
M.A. Krasnov🇷🇺 · D.Z. Berkimbayev🇰🇿 · A. Addazi🇨🇳 · Y. Aldabergenov🇰🇿 · M.Y. Khlopov🇫🇷
In this paper we consider complex scalar field with Mexican hat potential coupled with Gauss-Bonnet scalar resulting in restored U(1) symmetry at the stage of inflation, corresponding to the modern cosmological horizon. In our model, the phase transition takes place during inflation, avoiding large-scale axion isocurvature perturbations. Our model provides strong primordial inhomogeneities on small scales and ultra-light axion-like particle as either a fuzzy dark matter candidate or a candidate for inhomogeneous dark energy. We also study the possibility of black hole formation and gravitational wave background in this scenario. We find that in the case when the symmetry breaking field does not backreact on inflation, black hole production is not feasible. However, under specific conditions, gravitational waves fitting the NANOGrav band can be obtained.
↳ hep-thhep-ph0 citations
55
Mapping deep-mantle compositional heterogeneity using a directional geoneutrino detector
Zhihao Xu🇯🇵 · Misaki Hosoya🇯🇵 · William F. McDonough🇨🇳 · Taichi Sakai🇯🇵 · Hiroko Watanabe🇯🇵
Determining the spatial distribution of heat-producing elements (HPEs) within the Earth is critical for understanding the planet's thermal and chemical evolution. A central debate is whether the deep mantle, particularly the Large Low-Velocity Provinces (LLVPs), retains anomalous, radiogenically enriched reservoirs. While mapping surface variations in geoneutrino flux offers a direct probe of Earth's internal radioactivity, current continental-located detectors measure only the angle-integrated flux. This limitation creates a fundamental parameter degeneracy, rendering it impossible to distinguish a chemically homogeneous mantle from a heterogeneous one. In this study, we quantify the potential of directional geoneutrino detection to overcome this limitation. By evaluating realistic LLVP geometries under the experimental framework of the proposed Ocean Bottom Detector (OBD), we demonstrate that resolving the incoming direction of geoneutrinos can successfully break the non-uniqueness inherent in rate-only measurements. These results indicate that future directional geoneutrino measurements could help determine whether LLVPs host enhanced HPE abundances and assess their contribution to Earth's radiogenic heat budget. Such measurements would provide a new observational constraint on the chemical heterogeneity of the deep mantle and its role in Earth's long-term thermal evolution.
↳ physics.geo-phastro-ph.EPastro-ph.IMhep-ex+11 citation
56
Multi-band cross-correlation dark sirens: Enhancing cosmological parameter and gravitational-wave bias constraints
Ji-Yu Song🇨🇳 · Ya-Nan Du🇨🇳 · Yue-Yan Dong🇨🇳 · Jing-Fei Zhang🇨🇳 · Xin Zhang🇨🇳
Multi-band gravitational-wave (GW) observation, combining space-borne and ground-based detectors across different frequency bands, can improve the sky localization of compact binary sources by two to three orders of magnitude compared to single-band detection. This enhancement is crucial for cross-correlation dark siren analyses, since the sky localization uncertainty directly determines the noise level of the GW angular power spectrum. In this work, we present the first Fisher forecast for cross-correlation dark siren cosmology with multi-band GW observations, cross-correlating GW events from the Einstein Telescope (ET), Cosmic Explorer (CE), and B-DECIGO with the Chinese Space-station Survey Telescope photometric galaxy survey. We compare three network configurations: the multi-band B-DECIGO+ET+2CE (BDET2CE), the ground-only ET+2CE (ET2CE), and B-DECIGO alone. In the $Λ$ CDM model, BDET2CE achieves $σ (h) / h = 0.35%$ , improving by $37%$ over the ground-only ET2CE ( $0.55%$ ) and by $86%$ over B-DECIGO alone ( $2.45%$ ). Extending to the $w_{0} w_{a}$ CDM framework, the multi-band advantage on cosmological parameters becomes more moderate, with BDET2CE improving $σ (h) / h$ by $\sim 4%$ over ET2CE and $\sim 22%$ over B-DECIGO. The most striking advantage of multi-band observation lies in the per-bin measurement of the GW clustering bias $b_{GW} (z)$ : at $z \sim 1 - 2$ , BDET2CE constrains the bias to $\sim 3%$ precision, compared to $\sim 8 - 60%$ for ET2CE and $\sim 20 - 33%$ for B-DECIGO. These precise, redshift-resolved bias measurements open a new avenue for probing the astrophysics of compact binary mergers, enabling constraints on formation channels such as isolated binary evolution and dynamical assembly that predict distinct clustering signatures.
↳ astro-ph.COastro-ph.HEgr-qchep-ph+13 citations
57
Axion-Sourced Gravitational Waves in $B - L$ Hybrid Inflation
Ahmed Ayad🇪🇬 · Shaaban Khalil🇪🇬
Minimal supersymmetric $B - L$ hybrid inflation predicts a negligible vacuum tensor-to-scalar ratio $r_{vac} \sim 1 0^{- 8}$ due to its extremely flat potential. In this letter, we show that adding a spectator pseudoscalar axion-like field coupled to the $U (1)_{B - L}$ gauge sector via a Chern-Simons term circumvents this suppression. The rolling axion triggers a tachyonic instability for one gauge field helicity, exponentially amplifying gauge fluctuations. These sourced modes generate a stochastic gravitational-wave background with tensor power spectrum $P_{T}^{src} \propto e^{4 π ξ} / ξ^{6}$ , where $ξ = α ϕ ˙ / (2 f_{a} H)$ is the gauge-field instability parameter. For $ξ \sim 3.3$ -- $3.6$ , the tensor-to-scalar ratio reaches $r \sim 1 0^{- 3}$ , within the sensitivity of LiteBIRD. For $ξ \sim 3.6$ , the gravitational-wave spectrum develops a peaked shape that enters the LISA sensitivity band (peaking at frequencies around $1 0^{- 3}$ Hz) with an amplitude $h^{2} Ω_{GW} \sim 2.5 \times 1 0^{- 13}$ . The mechanism predicts chiral gravitational waves, a broken consistency relation $r = 16 ϵ$ , and a distinctive $r$ -- $Ω_{GW}$ correlation that could be tested by future CMB and interferometer observations.
↳ astro-ph.COhep-ph0 citations
58
Dressed Fock Spaces in Gauge Theory and Gravity
Sangmin Choi🇳🇱 · Prahar Mitra🇬🇧
Four-dimensional gauge and gravitational theories exhibit long-range interactions that require asymptotic particles to be dressed by clouds of soft photons and gravitons. Faddeev-Kulish dressings render scattering amplitudes infrared-finite, but the resulting multi-particle states do not factorise into tensor products of dressed one-particle states. We show that this loss of Fock-space factorisation is not fundamental, but reflects an inappropriate choice of infrared variables. The real soft divergence is reproduced by the Goldstone modes of asymptotic symmetries, while the Coulomb phase is reproduced by new zero modes of the radiative fields that we introduce here. In these variables, infrared-finite dressed multi-particle states admit the usual Fock-space factorisation into single-particle dressed states.
↳ hep-thgr-qchep-ph1 citation
59
The O(4)-breaking bubble
Guy Avraham🇮🇱 · Kfir Blum🇮🇱 · Omri Rosner🇮🇱 · Isaac G. Smith🇮🇱
False vacuum decay in field theory is thought to be dominated by Coleman's O(4)-symmetric bounce, the minimum action nontrivial solution of the imaginary time equations of motion. Beyond the bounce, non-constructive existence proofs of O(4)-breaking solutions are available in the mathematics literature, but the solutions themselves, and their physics, have remained unknown. Considering the simple, bounded-below, scalar field potential $V (ϕ) = \frac{m ^{2}}{2} ϕ^{2} - \frac{λ}{4} ϕ^{4} + \frac{g}{6} ϕ^{6}$ , we construct a nonradial solution explicitly: two bubble-tubes of opposite sign wrapping orthogonal rings, invariant under $O (2) \times O (2)$ rotations combined with a parity that exchanges the rings. The solution admits valid Cauchy data for real time evolution from a $t = 0$ slice, and supports an odd number of unstable deformation modes.
↳ hep-thgr-qchep-ph2 citations
60
Ultraviolet Structure of Real-time Gravitational Wave Linear Response in a Resonant Scalar Field
Han Lai🇨🇳 · Atsuhisa Ota🇨🇳
We study the real-time linear response of gravitational waves in a time-dependent resonant scalar field in a Minkowski background. In the Schwinger-Keldysh formalism, we develop an adiabatic regularization scheme for unequal-time correlation functions and use it to extract the ultraviolet structure of the one-loop response. The leading divergence reproduces the familiar $□^{2} h_{ij}$ structure, whereas the time-dependent background induces additional local divergences proportional to $□ h_{ij}$ , $\partial_{0} h_{ij}$ , and $h_{ij}$ . These are renormalized by local counterterms associated with the Weyl-squared term, a time-dependent Ricci-scalar term, and a time-dependent cosmological constant. We also compare the renormalization of the linear response with that of the tadpole stress tensor and find a mismatch beyond leading adiabatic order in the present toy model. By considering a covariant completion of the resonance, we further argue that this mismatch is tied to the off-shell nature of the fixed background, and is expected to disappear once the background is treated on shell.
↳ gr-qcastro-ph.COhep-phhep-th0 citations
61
Modification of heavy quark hadronization in high-multiplicity collisions at LHCb
Chenxi Gu🇫🇷
The ratio of heavy flavor hadrons is very sensitive to the hadronization mechanism. This proceeding will present recent LHCb results on the cross-section ratios of $D_{s}^{+} / D^{+}$ , $Ξ_{c}^{+} / Λ_{c}^{+}$ and $Λ_{b}^{0} / B^{0}$ in different collision systems. The significantly enhanced production ratios $D_{s}^{+} / D^{+}$ and $Λ_{b}^{0} / B^{0}$ with the increase of multiplicity may imply that hadronization mechanisms are modified in high-multiplicity events.
↳ hep-exhep-phEPJ Web Conf.(2024)·0 citations
62
Revisiting the Lyth bound constraints on inflation from ACT DR6 results
Rui Yang🇨🇳 · Jun Tao🇨🇳 · Peng Wang🇨🇳 · Mian Zhu🇨🇳
The Lyth bound asserts that the field excursion of inflaton must be sub-Planckian, thereby imposing an upper bound on the amplitude of the tensor power spectrum in inflationary scenario. This bound is conventionally derived assuming a scale-invariant curvature power spectrum, i.e., $n_{s} = 1$ . However, astrophysical observations confirm a red-tilted spectrum with $n_{s} < 1$ . In light of recent results from the Atacama Cosmology Telescope (ACT) DR6, we revisit these constraints using the newly implied scalar spectral index of $n_{s} ≃ 0.9743$ . Incorporating the ACT data yields a different upper bound on the tensor-to-scalar ratio $r$ , which can potentially exclude inflationary scenarios previously robust under the original Lyth bound with $n_{s} = 1$ . Our result highlights the urgent need to combine theoretical Lyth bound considerations with the most up-to-date astrophysical data.
↳ astro-ph.COgr-qchep-ph2 citations
63
Direct calculation of parton distributions in momentum space from lattice QCD
Anthony V. Grebe🇺🇸 · Daniel C. Hackett🇺🇸 · Michael L. Wagman🇺🇸 · Rui Zhang🇺🇸 · Yong Zhao🇺🇸
Coulomb-gauge quasi-parton distributions can be computed directly in momentum space on a finite lattice, enabled by the commutativity of their renormalization and Fourier transform. This approach removes the formal inverse problem in coordinate-space methods. Our momentum-space pion quasi-distributions agree with coordinate-space results Fourier transformed with asymptotic extrapolation, indicating that the formal inverse problem in the latter is not a concern at this volume. We further extend the framework to higher dimensions and obtain the first 3D image of the pion directly from lattice QCD.
↳ hep-lathep-phnucl-th3 citations
64
Quantum gravity and spectral running cutoff
Carlo Branchina🇮🇹 · Vincenzo Branchina🇮🇹 · Filippo Contino🇮🇹 · Riccardo Gandolfo🇮🇹 · Arcangelo Pernace🇮🇹
We have recently shown that a natural way to implement the Wilsonian paradigm in gauge theories is through the introduction of a ``spectral cutoff", a cut on the eigenvalues of the covariant Laplacian, pointing out that this provides the route toward the renormalization group (RG) construction. Here we apply this idea to quantum gravity, resorting to two realizations of the spectral running cutoff: ``hard" and ``smooth". We derive the RG equations for the Newton and cosmological constant and find the RG pattern of the asymptotic safety scenario, with a non-Gaussian UV-attractive fixed point.
↳ hep-thgr-qchep-ph0 citations
65
Galaxy-cluster-stacked Fermi-LAT, part IV: $\sim 70$ GeV WIMP annihilation lines
Uri Keshet🇮🇱
The strongest constraints on the velocity-dependent ( $p$ -wave) annihilation of weakly interacting massive particle (WIMP) dark matter were derived from the deep potential wells of galaxy clusters. Even weaker signals can be extracted from sufficient aggregated clusters, by cross-correlating $γ$ -rays with large-scale structure tracers or stacking over extensive cluster catalogs. Three independent such analyses show a similar triad of emission lines in Fermi-LAT data, around 70, 40, and 13 GeV, emerging from featureless spectra in each hemisphere upon cross-correlation with eROSITA maps, and in stacked MCXC, eROSITA, and DESI catalog clusters only once boosted to the cluster frame. These lines fit the anticipated $χχ \to γ γ$ , $γ Z$ , and $γ h$ annihilation channels of a $\sim 70$ GeV WIMP $χ$ , detected by composite matched filters at trial-corrected global $Z$ -scores reaching $5.6 σ$ (cross-correlations) and $2.3 σ$ (stacking), with intrinsic $\sim 1 0^{[- 20, - 19]}$ cm $^{3}$ s $^{- 1}$ channel cross-sections. High-resolution spectra establish six lines and an unresolved ( $2$ -- $3$ line) feature in total, naturally aligned with the anticipated nine channels of two cross-annihilating WIMPs of masses $67. 3_{- 0.1}^{+ 0.1}$ and $71. 4_{- 0.1}^{+ 0.2}$ GeV (profile-likelihood bounds; $_{- 5%}^{+ 3%}$ systematic; $5.3 σ$ ). The Galactic-center GeV excess is broadly consistent with the corresponding broad annihilation continuum.
↳ astro-ph.HEastro-ph.COhep-ph1 citation

Affiliations

first authorsco-authorsvia INSPIRE