Tue·Jul 22, 2025Tuesday·July 22, 2025

1. 01*

   Speed of sound peak in isospin QCD: a natural prediction of the Medium Separation Scheme

   Bruno S. Lopes🇧🇷 · Dyana C. Duarte🇧🇷 · Ricardo L. S. Farias🇧🇷 · Rudnei O. Ramos🇧🇷

   We present predictions for the zero-temperature equation of state at finite isospin density using the Nambu-Jona-Lasinio (NJL) model within the medium separation scheme (MSS) -- a scheme that explicitly disentangles medium effects from the ultraviolet divergent vacuum terms. Recent lattice QCD results reveal a nonmonotonic speed of sound ($c_s^2$) as a function of isospin chemical potential (${\mu }_I$), exhibiting explicit violation of the conformal bound $c_s^2=1/3$. These findings have attracted significant theoretical interest, as established models -- including the NJL model -- failed to anticipate this behavior prior to lattice simulations. Conventional NJL implementations yield unphysical artifacts, often attributed to regularization scale sensitivity stemming from nonrenormalizability. However, in this work, we demonstrate that the standard NJL framework combined with MSS quantitatively reproduces state-of-the-art lattice data for isospin QCD.

   hep-phastro-ph.HEhep-lathep-th+1PRD(2025)·15 citations
2. 02*

   Excitonic contributions to dark matter-electron scattering

   Nora Taufertshöfer🇨🇭 · Vanessa Zema🇩🇪 · Riccardo Catena🇸🇪 · Valerio Olevano🇫🇷 · Nicola A. Spaldin🇨🇭

   We determine whether excitonic effects affect predictions of dark matter (DM)-electron scattering rates by calculating the energy- and momentum-dependent energy-loss function, including electron-hole interaction excitonic effects, for the dark-matter scintillating detector materials GaAs and NaI. By comparing our results using the Bethe-Salpeter equation in the framework of many-body perturbation theory, which explicitly includes excitonic effects, with those using the quasiparticle random-phase approximation, which includes only electron-electron interaction and crystal local-field effects, we find that excitonic effects in NaI significantly increase the predicted scattering rate at low energy and as a result improve the cross-section sensitivity considering a realistic background. In contrast, the predicted scattering rate and the DM-electron scattering cross-section for GaAs are minimally affected by excitonic effects.

   hep-phcond-mat.mtrl-sciPRResearch(2026)·2 citations
3. 03*

   Goldstone bosons across thermal phase transitions

   Peter Lowdon🇩🇪 · Owe Philipsen🇩🇪

   Temperature has a significant effect on the properties of quantum field theories (QFTs) with a spontaneously broken symmetry, in particular on the massless Goldstone bosons that exist in the vacuum state. It has recently been shown using lattice calculations for a $\mathrm{U}(1)$ complex scalar field theory that the Goldstone mode persists even when the symmetry is restored above the critical temperature $T_c$, and has the properties of a screened excitation, a so-called thermoparticle. In this work, we continue the investigation of this theory by determining explicitly how the Goldstone mode evolves as the temperature is increased both below and above $T_c$. We find that the two phases of the theory are entirely characterised by the thermal dissipative effects experienced by the Goldstone mode, with the broken and symmetry-restored phases associated with weak and strong damping, respectively. These findings are consistent with the non-perturbative constraints imposed by spontaneous symmetry breaking, and provide a new way in which to characterise thermal phase transitions in QFTs.

   hep-phhep-lathep-thnucl-thJHEP(2026)·4 citations
4. 04*

   Susceptibilities and Taylor coefficients of magnetic QCD from perturbation theory

   Eduardo S. Fraga🇧🇷 · Letícia F. Palhares🇧🇷 · Tulio E. Restrepo🇺🇸

   We compute the coefficients $c_2(T,B)$ and $c_4(T,B)$ of the Taylor expansion for the pressure in powers of ${\mu }_B/T$ in the presence of a large magnetic field within perturbative QCD at finite temperature and baryon density up to two-loops for $N_f=3$ flavors with physical quark masses. We also present results for the excess of pressure, baryon density and baryon number susceptibility as functions of ${\mu }_B$, as well as susceptibilities as functions of the temperature in the $\{{\mu }_B,{\mu }_Q,{\mu }_S\}$ basis. Our results can be directly compared to recent lattice QCD data. Even though current lattice results do not overlap with its region of validity, perturbative results seem to be compatible with those obtained on the lattice for large temperatures.

   hep-phhep-thPRD(2026)·3 citations
5. 05*

   The Supersymmetric Standard Model, combined with a special Exotic Invariant, yields a new kind of SUSY mass splitting (E6)

   John A. Dixon🇨🇦

   Exotic Invariants, with Lorentz invariance, have been found in the BRS cohomology of SUSY in 3+1 dimensions. Until recently, it was generally accepted that no such objects could exist. It is shown here that the Supersymmetric Standard Model (``the SSM'') can be coupled to a special Exotic Invariant to form a new model, which we call the Exotic Model (``the XM'') . This Exotic Model continues to generate the usual Vacuum Expectation Value (``VEV'') that breaks gauge symmetry from SU(3) X SU(2) X U(1) to SU(3) X U(1) But now, from the same VEV, the Exotic Model also generates SUSY violating mass splitting of the neutral ``ZX'' sector at tree level. This is possible because the Exotic Model changes the algebra of SUSY. This ``ZX'' sector is flavour neutral, which might explain the suppression of flavour changing neutral currents observed in experiments. The Exotic Model is governed by a very restrictive Master Equation, so there should be a very small number of parameters in it.

   hep-phhep-th5 citations
6. 06*

   On the Impossibility of Obtaining Time-Independent, Three-Dimensional, Spherically-Symmetric Densities of Confined Systems of Relativistically Moving Constituents

   Gerald A. Miller🇺🇸

   The quantum mechanical definition of probability, the uncertainty principle and Poincare invariance provide strong basic restrictions on the ability to define spatial densities associated with form factors describing the properties of confined systems of relativistically moving constituents. Despite this, many papers ignore one or more of these restrictions. Here I show how to obtain time-independent, two-dimensional densities that are consistent with the stated restrictions. This is done using the light-front, infinite momentum frame formalism. Two-dimensional density interpretations of the axial-vector form factor and all three gravitational form factors are obtained. Additionally, an expression of a two-dimensional mass density related to the trace of the energy momentum tensor is obtained. I also show that all known methods for finding three-dimensional densities: using the Breit frame, Abel transformations, Wigner distributions and spherically-symmetric wave packets with vanishing spatial extent violate the basic restrictions in different manners. Furthermore, the use of the latter leads to densities that vanish almost everywhere in space as time increases from an initial value.

   hep-phnucl-exnucl-thPRC(2025)·10 citations
7. 07*

   Comments on Exploring Quantum Statistics for Dirac and Majorana Neutrinos using Spinor-Helicity technique (arXiv:2507.07180 [hep-ph])

   C. S. Kim🇰🇷 · M. V.N. Murthy🇮🇳 · Dibyakrupa Sahoo🇵🇱

   We give our comments on Ref. [1](arXiv:2507.07180) which critiques our idea of exploring quantum statistics to distinguish between Dirac and Majorana neutrinos proposed in some of our earlier works [2-4]. The ad-hoc symmetrization of the Dirac case amplitude square advocated in Eqs. (16) and (35) of [1] has no physical basis and it leads to violation of lepton number in the the standard model for Dirac neutrinos. Therefore, this symmetrization by hand is in principle incorrect.

   hep-phhep-exhep-th0 citations
8. 08*

   Determination of Fragmentation Functions from Charge Asymmetries in Hadron Production

   Jun Gao🇨🇳 · ChongYang Liu🇨🇳 · Bin Zhou🇨🇳

   We propose a novel method for extracting non-singlet (NS) fragmentation functions (FFs) of light charged hadrons from charge asymmetries measured in hadron fragmentation, using data from both single-inclusive electron-positron annihilation and semi-inclusive deep-inelastic scattering processes. We determine the NS FFs for pions and kaons at next-to-next-to-leading order in Quantum Chromodynamics, including a comprehensive uncertainty analysis. The extracted FFs reveal a scaling index of about 0.7 at large momentum fractions and low energy scales, a strangeness suppression factor of about 0.5, and universality in fragmentation of light mesons. Our findings provide a valuable benchmark for testing non-perturbative QCD models and Monte Carlo event generators, and serve as crucial input for future electron-ion colliders.

   hep-phhep-exCPC(2026)·1 citation
9. 09*

   The Cosmic Horizon of Neutrinos

   James Fardeen🇺🇸 · Stefano Profumo🇺🇸 · M. Grant Roberts🇺🇸

   The persistent discrepancy between the experimental measurement and the Standard Model (SM) prediction of the muon's anomalous magnetic moment $(g-2{)}_{\mu }$ remains one of the most intriguing hints of physics beyond the SM. A well-motivated explanation involves a light $Z^{\prime }$ gauge boson associated with a broken $U(1{)}_{L_{\mu }-L_{\tau }}$ symmetry. Such a boson not only resolves the $(g-2{)}_{\mu }$ anomaly, but also induces resonant interactions between high-energy cosmic neutrinos and the cosmic neutrino background (C$\nu$B), potentially shaping the observable neutrino flux at Earth. In this work, we explore the implications of such interactions for the cosmic propagation of high-energy neutrinos. We compute the optical depth for neutrino attenuation via $Z^{\prime }$-mediated scattering, accounting for neutrino masses, hierarchies, and thermal distributions. We delineate the regions in $(m_{Z^{\prime }},m_{\nu })$ space where the optical depth exceeds unity, defining a ``neutrino cosmic horizon'' beyond which high-energy neutrinos are significantly attenuated. We confront these results with the parameter space required to simultaneously explain the muon $g-2$ anomaly and ease the Hubble tension via an additional contribution to the effective number of relativistic degrees of freedom, $\Delta N_{\mathrm{eff}}\simeq 0.2-0.5$. Our analysis reveals a consistent region in parameter space where all three phenomena-$(g-2{)}_{\mu }$, $N_{\mathrm{eff}}$, and high-energy neutrino attenuation-can be explained by the same light mediator. These findings motivate future searches for spectral features in IceCube and its next-generation successors as indirect probes of new physics in the neutrino sector.

   hep-phastro-ph.COPRD(2026)·0 citations
10. 10*

    Mechanical properties of the ${\Omega }^{-}$ baryon from gravitational form factors

    Zeinab Dehghan🇮🇷 · K. Azizi🇮🇷

    We present a comprehensive investigation of the mechanical properties of the ${\Omega }^{-}$ baryon by analyzing its gravitational form factors (GFFs) within the framework of QCD sum rules. These form factors encode rich information about the internal structure of hadrons and offer deep insights into the dynamics that govern their stability. The spin-3/2 nature of the ${\Omega }^{-}$ baryon manifests in its gravitational form factors as intricate multipole structures, which encapsulate higher-order deformations and demonstrate the influence of intrinsic spin on internal dynamics. We extract the GFFs of the ${\Omega }^{-}$ baryon and apply their specific multipole combinations, gravitational multipole form factors (GMFFs), to quantify key mechanical observables-including energy density, angular momentum, pressure and shear force distributions, mass and mechanical radii, and D-terms-associated with different multipole orders. Notably, this work provides the first determination of several of these observables, such as the mechanical radii and the quadrupole contributions to the pressure and shear force distributions. Our analysis shows that the quadrupole contributions to the mechanical properties are generally subdominant compared to those from the monopole component. We further investigate the mechanical stability of the ${\Omega }^{-}$ through a multipole analysis of its internal force distributions. These results enhance our understanding of the mechanical structure of spin-3/2 hadrons and provide useful benchmarks for future theoretical and lattice QCD studies.

    hep-phhep-exhep-latPRD(2025)·8 citations
11. 11*

    First Extraction of the $\varphi$-${}^4\mathrm{He}$ scattering length from near-threshold $\varphi$ photoproduction on helium-4

    Chengdong Han🇨🇳 · Wei Kou🇨🇳 · Rong Wang🇨🇳 · Xurong Chen🇨🇳

    We present a model-independent extraction of the phi-4He scattering length from near-threshold phi photoproduction on helium-4, based on LEPS Collaboration data for the coherent process gamma + 4He -> phi + 4He and the Vector Meson Dominance framework. Assuming an energy-independent differential cross section, we extract the absolute value of the phi-4He scattering length |alpha_{phi4He}| = (3.33 +- 0.06) x 10^{-4} fm from a fit at threshold t_thr. This value is orders of magnitude smaller than those for phi-N and phi-d scattering lengths, indicating an inverse dependence of |alpha_VA| on the target nucleus mass. Our results provide new insight into the phi-nucleus interaction, supporting the notion of weak phi-nucleus coupling. We further explore the dependence of |alpha_VA| on the vector meson mass, the target atom mass, and the threshold energy. An approximate exponential suppression of |alpha_VA| is observed with increasing vector meson mass or target atom mass, indicating that heavier vector mesons or heavier target nuclei exhibit weaker couplings in vector meson-nucleus interactions.

    hep-phnucl-thEPJC(2025)·0 citations
12. 12*

    Phenomenology of scalar particles assisted by machine learning

    E. A. Herrera-Chacón

    In this thesis, we explore the phenomenology of scalar particles within Beyond Standard Model frameworks, using Machine Learning (ML) techniques to enhance sensitivity and discovery potential at current and future collider experiments, the Large Hadron Collider (LHC) and the High-Luminosity LHC (HL-LHC). Specifically, we study scalar extensions of the Standard Model such as the Two Higgs Doublet Model Type-III (2HDM-III) and the Froggatt-Nielsen Flavon model. We perform a detailed collider analysis focusing on charged Higgs boson pair production within the 2HDM-III, examining final states involving muons, neutrinos and quark jets. Our studies identify parameter regions consistent with recent experimental anomalies reported by ATLAS collaboration, particularly in charged Higgs decays involving charm-bottom quark transitions, and suggest concrete scenarios for achieving statistically significant signals of 5$\sigma$ at future luminosities. In the context of the Flavon model, we analyse potential signatures of a new scalar called Flavon decaying into a Higgs boson and a pair of bottom quarks, followed by the channels where the Higgs decays into a pair of bottom quarks or a pair of photons. Additionally, we analyse Lepton-Flavour-Violating processes, both of them achieving discovery level significances of up to $5\sigma$ at the HL-LHC. Using multivariate analysis techniques, specifically Boosted Decision Trees, we demonstrate a significant improvement in signal discrimination. Throughout this thesis, ML methodologies have been integral, notably enhancing the signal from background separation and significantly improving the robustness of phenomenological predictions. The methods and analyses presented here contribute to clarifying the flavour structure mysteries of the SM and offer actionable targets for future experimental searches.

    hep-phPhys.Rev.D 111 (2025) 015023; Phys.Rev.D …
13. 13*

    Leading vector coupling in baryon semileptonic decays in large-$N_c$ chiral perturbation theory revisited: Extension to decuplet baryons

    Ruben Flores-Mendieta🇲🇽 · Guillermo Sanchez-Almanza🇲🇽

    The leading vector coupling defined in the semileptonic decay of a baryon is revisited in the framework of large-$N_c$ baryon chiral perturbation. Aspects of $SU(3)$ flavor symmetry breaking are taken into account in two ways: Explicitly through perturbative symmetry breaking and implicitly through the integrals occurring in the one-loop corrections. The analysis of perturbative breaking is performed by using flavor projection operators which are exceptionally helpful in understanding previously unidentified issues. The approach is extended to theoretically evaluate the leading vector coupling in the transition ${\Omega }^{-}\to {{\Xi }^{\ast }}^0$. A fitting procedure to data reveals that second-order symmetry breaking corrections, while small, can have a significant impact on the evaluation of the baryon vector coupling, potentially increasing its overall strength due to the involved interplay of both explicit and implicit contributions.

    hep-ph1 citation
14. 14*

    Simulation-Prior Independent Neural Unfolding Procedure

    Anja Butter🇩🇪 · Theo Heimel🇧🇪 · Nathan Huetsch🇩🇪 · Michael Kagan🇺🇸 · Tilman Plehn🇩🇪

    Machine learning allows unfolding high-dimensional spaces without binning at the LHC. The new SPINUP method extracts the unfolded distribution based on a neural network encoding the forward mapping, making it independent of the prior from the simulated training data. It is made efficient through neural importance sampling, and ensembling can be used to estimate the effect of information loss in the forward process. We showcase SPINUP for unfolding detector effects on jet substructure observables and for unfolding to parton level of associated Higgs and single-top production.

    hep-phcs.LGhep-ex13 citations
15. 15*

    Is the shear induced spin polarization non-dissipative?

    Jia-Rong Wang🇨🇳 · Shuo Fang🇨🇳 · Di-Lun Yang🇹🇼 · Shi Pu🇨🇳

    The shear-induced polarization plays a crucial role in understanding the local polarization of $\Lambda$ and $\overline{\Lambda }$ hyperons. A key puzzle is whether the shear-induced polarization is non-dissipative or not. In this work, we analyzed the shear-induced polarization and the anomalous Hall effects using the entropy flow and H-theorem introduced from quantum (chiral) kinetic theory. While the shear-induced polarization and the anomalous Hall effect do not directly contribute to the entropy production rate, the perturbations associated with the shear tensor lead to an increase in entropy, similar to the role of the shear tensor in classical kinetic theory. We also examined these effects within the framework of linear response theory using Zubarev's approach. The analysis of time-reversal transformation on the spin current in coordinate space suggests that shear-induced polarization violates time-reversal symmetry and, therefore, should vanish. However, a similar analysis of the Wigner function in phase space does not impose any additional constraints on shear-induced polarization, allowing it to persist in phase space as expected. This discussion indicates that time-reversal analysis in coordinate space alone may not be sufficient to determine whether an effect is dissipative. Furthermore, our analysis based on Zubarev's approach suggests that these effects may indeed possess a dissipative nature. These findings highlight the limitations of the current theoretical framework in fully characterizing the dissipative properties of these phenomena.

    hep-phhep-thnucl-thPRD(2026)·5 citations
16. 16*

    Timelike electromagnetic form factors of hyperons at large $q^2$

    G. Ramalho🇰🇷 · M.T. Peña🇵🇹 · K. Tsushima🇧🇷 · Myung-Ki Cheoun🇰🇷

    In the last few years there has been considerable progress in the study of the electromagnetic form factors of baryons in the timelike region, through electron-positron scattering, with increasing squared transfer momentum $q^2$. The modulus of the electric ($G_E$) and magnetic ($G_M$) form factors has been measured for nucleons, hyperons and other baryons at BaBar, CLEO, Belle and BESIII. The novel measurements motivated the extension of a covariant quark model, developed to the spacelike region ($q^2\le 0$), to the timelike region, without any further parameter fitting. The extension is based on asymptotic relations derived from analyticity and unitarity, valid for the large-$q^2$ region. We use the model to make predictions for the effective form factor $|G|$ (combination of $G_E$ and $G_M$) and the ratio $|G_E/G_M|$ for spin 1/2 hyperons at large $q^2$ (above 10 GeV${}^2$). Our calculations are in good agreement with the data from CLEO and BESIII for $\Lambda$, ${\Sigma }^{+}$ and ${\Xi }^{-}$ above $q^2=15$ GeV${}^2$. Upcoming data for ${\Sigma }^0$, ${\Sigma }^{-}$ and ${\Xi }^{-}$ at large $q^2$ may be used to further test our predictions. We also compare our model calculations with the scarce available data for $|G_E/G_M|$. We conclude that the present $q^2$ range is not large enough to test our calculations, but that a more definitive test can be made by experiments above $q^2=20$ GeV${}^2$.

    hep-phhep-exhep-latnucl-exPoS(2026)·2 citations
17. 17*

    Long-lived Axion-Like Particles from Tau Decays

    Yohei Ema🇨🇭 · Patrick J. Fox🇺🇸 · Matheus Hostert🇺🇸 · Tony Menzo🇺🇸 · Maxim Pospelov🇺🇸 · Anupam Ray🇺🇸 · Jure Zupan🇺🇸

    Axion-like particles (ALPs) are well-motivated examples of light, weakly coupled particles in theories beyond the Standard Model. In this work, we study long-lived ALPs coupled exclusively to leptons in the mass range between $2m_e$ and $m_{\tau }-m_e$. For anarchic flavor structure the leptophilic ALP production in tau decays or from ALP-tau bremsstrahlung is enhanced thanks to derivative couplings of the ALP and can surpass production from electron and muon channels, especially for ALPs heavier than $m_{\mu }$. Using past data from high-energy fixed-target experiments such as CHARM and BEBC we place new constraints on the ALP decay constant $f_a$, reaching scales as high as $\mathcal{O}(10^8)$~GeV in lepton-flavor-violating channels and $f_a\sim \mathcal{O}(10^2)$~GeV in lepton-flavor-conserving ones. We also present projections for the event-rate sensitivity of current and future detectors to ALPs produced at the Fermilab Main Injector, the CERN SPS, and in the forward direction of the LHC. We show that SHiP will be sensitive to $f_a$ values that are over an order of magnitude above the existing constraints.

    hep-phhep-exPRD(2025)·16 citations
18. 18*

    Spin correlations and Bell nonlocality in $\Lambda \bar{\Lambda }$ pair production from $e^{+}{e}^{-}$ collisions with a thrust cut

    Shi-Jia Lin🇨🇳 · Ming-Jun Liu🇨🇳 · Ding Yu Shao🇨🇳 · Shu-Yi Wei🇨🇳

    We present a comprehensive theoretical study of spin correlations in $\Lambda \bar{\Lambda }$ production from $e^{+}{e}^{-}$ annihilation, providing the theoretical predictions for the Belle II experiment. Using soft-collinear effective theory, we perform the first resummation of large logarithms for the longitudinal ($C_{LL}$) and transverse ($C_{TT}$) spin correlations for events with a cut on the thrust variable. Our calculation achieves next-to-next-to-leading logarithmic accuracy and incorporates the determination of polarized fragmenting jet functions. This framework provides robust predictions with significantly reduced theoretical uncertainties compared to fixed-order parton model approaches. Furthermore, we establish a direct mapping between the experimentally accessible spin correlation, $C_{TT}$, and a testable CHSH-Bell inequality. This result reframes $C_{TT}$ as a quantitative probe of quantum decoherence, providing a novel tool to measure the degree of parton-level entanglement that survives the fragmentation and hadronization process.

    hep-phhep-exnucl-exnucl-thJHEP(2025)·31 citations
19. 19*

    Measurement of the mass of Higgs boson through HZ production at FCC-ee

    I.Kahraman (Ankara Univ.)🇹🇷 · O.Çakır (Ankara Univ.)🇹🇷

    The associated production of a Higgs boson with a $Z$ boson in the collisions of electron and positron beams at Future Circular Collider (FCC-ee) have been studied. Here, the $Z$ boson decays into dileptons, while the Higgs boson decays to all possible channels, mostly to the $b\bar{b}$. The collisions provide a clean and powerful channel to probe the ($HZZ$) coupling at future lepton colliders. Following the event generation, the analysis is performed using the recoil mass method, which allows model-independent reconstruction of the Higgs boson depending on the kinematics of the final-state leptons. This method enables precise identification of the Higgs signal peak independent of its decay mode and significantly reduces systematic uncertainties. The recoil mass distributions from the signal process ($e^{+}{e}^{-}\to HZ$, $Z\to l^{+}{l}^{-}$) and the main backgrounds ($ZZ$, $WW$, $t\bar{t}$ and other standard model processes) have been analyzed using a dedicated analysis code. Monte Carlo simulations corresponding to an integrated luminosity of $5$ ab${}^{-1}$ have been used for the analysis, assuming the high performance of the IDEA detector concept. The results are presented for center-of-mass energies of $\sqrt{s}=240$ GeV and $\sqrt{s}=365$ GeV to compare the sensitivities and highlight the potential of future $e^{+}{e}^{-}$ colliders in probing the $HZZ$ interaction with high precision.

    hep-phActa Phys.Polon.B(2025)·2 citations
20. 20*

    A comprehensive approach to the physics of mesons

    Angel. S. Miramontes🇪🇸 · Jose M. Morgado Chavez🇪🇸 · Joannis Papavassiliou🇪🇸 · Jan M. Pawlowski🇩🇪

    We develop a novel approach for the self-consistent solution of coupled sets of Bethe-Salpeter and Schwinger-Dyson equations in QCD. This framework allows us to maintain the axial Ward-Takahashi identities of the theory within advanced approximation schemes, such as the skeleton or three-particle irreducible expansions. For this purpose we reformulate the Schwinger-Dyson equation of the axial-vector vertex such that the bulk of its quantum corrections is expressed in terms of a novel vertex. Crucially, this vertex satisfies a symmetry-induced relation of its own, which involves the full quark-gluon vertex. As a result, the Schwinger-Dyson equation reproduces the standard Ward-Takahashi identity satisfied by the axial-vector vertex. Consequently, the known relation between the quark mass function and the wave function of the pion in the chiral limit is duly fulfilled. The present approach offers valuable insights into the interplay between symmetry and dynamics, and provides a practical path towards computations of hadron physics within sophisticated approximations. In particular, the one-loop dressed truncation of the key dynamical equations, including that of the quark-gluon vertex, is shown to be completely compatible with the required symmetry relations. Further extensions and potential phenomenological applications of the developed framework are briefly discussed.

    hep-phhep-lathep-thEPJC(2025)·9 citations
21. 21*

    Toward an event-level analysis of hadron structure using differential programming

    Kevin Braga🇺🇸 · Markus Diefenthaler🇺🇸 · Steven Goldenberg🇺🇸 · Daniel Lersch🇺🇸 · Yaohang Li🇺🇸 · Jian-Wei Qiu🇺🇸 · Kishansingh Rajput🇺🇸 · Felix Ringer🇺🇸 · Nobuo Sato🇺🇸 · Malachi Schram🇺🇸

    Reconstructing the internal properties of hadrons in terms of fundamental quark and gluon degrees of freedom is a central goal in nuclear and particle physics. This effort lies at the core of major experimental programs, such as the Jefferson Lab 12 GeV program and the upcoming Electron-Ion Collider. A primary challenge is the inherent inverse problem: converting large-scale observational data from collision events into the fundamental quantum correlation functions (QCFs) that characterize the microscopic structure of hadronic systems within the theory of QCD. Recent advances in scientific computing and machine learning have opened new avenues for addressing this challenge using deep learning techniques. A particularly promising direction is the integration of theoretical calculations and experimental simulations into a unified framework capable of reconstructing QCFs directly from event-level information. In this work, we introduce a differential sampling method called the local orthogonal inverse transform sampling (LOITS) algorithm. We validate its performance through a closure test, demonstrating the accurate reconstruction of a test distribution from sampled events using Generative Adversarial Networks. The LOITS algorithm provides a central building block for addressing inverse problems involving QCFs and enables end-to-end inference pipelines within the framework of differential programming.

    hep-phhep-exPLB(2026)·1 citation
22. 22*

    Factorization and Resummation for the Nearside Energy-Energy Correlators

    Yuxun Guo🇺🇸 · Feng Yuan🇺🇸 · Wenbin Zhao🇺🇸

    By utilizing the di-hadron fragmentation formalism, we extend the previous factorization of nearside energy-energy correlators (EEC) in the collinear limit and derive an all order resummation in the Fourier transform $b_T$-space. A perfect matching is obtained when we compare to the fixed-order results. We further demonstrate the resummation effects for the EEC in $e^{+}{e}^{-}$ annihilation and show that they will significantly improve the theoretical predictions at small angles.

    hep-phPRL(2026)·21 citations
23. 23*

    Quantum Scaling in Energy Correlators Beyond the Confinement Transition

    Cyuan-Han Chang🇺🇸 · Hao Chen🇺🇸 · Xiaohui Liu🇨🇳 · David Simmons-Duffin🇺🇸 · Feng Yuan🇺🇸 · Hua Xing Zhu🇨🇳

    We study the QCD scaling behavior of the small-angle Energy-Energy Correlator (EEC), focusing on the transition between its perturbative pre-confinement and non-perturbative post-confinement regimes. Applying the light-ray Operator Product Expansion (OPE), we develop a formalism that describes the scaling of the EEC with the input energy $Q$ in the transition and the post-confinement region, where the latter quantum scaling is determined by the $J=5$ DGLAP anomalous dimension. A key result of our work is a novel connection between the light-ray OPE and the dihadron fragmentation function (DFF), where we show that the non-perturbative OPE coefficients correspond to moments of the DFF. This finding establishes a new paradigm for studying hadronization. Our theoretical predictions are validated against Monte Carlo simulations for both $e^{+}{e}^{-}$ and $pp$ collisions, showing excellent agreement. The potential role of the quantum scaling in the precision determination of ${\alpha }_s$ is also discussed.

    hep-phhep-exhep-thnucl-ex+1PRL(2026)·30 citations
24. 24*

    Weyl-invariant Einstein-Cartan gravity with a heavy ALP: Higgs Inflation and $\alpha$-attractors

    Georgios K. Karananas🇩🇪 · Mikhail Shaposhnikov🇨🇭 · Sebastian Zell🇩🇪

    We initiate the analysis of the inflationary dynamics in Weyl-invariant Einstein-Cartan gravity nonminimally coupled to the Standard Model of particle physics. We take the axion-like particle of gravitational origin to be heavy and show that inflation with the Higgs field can be accommodated in this framework.

    hep-phastro-ph.COgr-qchep-thPLB(2026)·7 citations
25. 25*

    Probing displaced (dark)photons from low reheating freeze-in at the LHC

    Paola Arias🇨🇱 · Bastián Díaz Sáez🇨🇱 · Lucía Duarte🇺🇾 · Joel Jones-Pérez🇵🇪 · Walter Rodriguez🇵🇪 · Danilo Zegarra Herrera🇵🇪

    We extend the Standard Model (SM) by introducing a $U(1{)}^{\prime }$ gauge boson and a real pseudo-scalar field, both odd under a ${\mathbb{Z}}_2$ symmetry. The resulting low-energy spectrum consists of a stable vector as the dark matter candidate, and a pseudo-scalar mediator, which interacts with the SM via a Higgs portal coupling and a dimension-five portal connecting it to both the dark and visible photons. We explore the freeze-in of both particles at low reheating temperature, finding a rich yield evolution dynamics in the early Universe. This setup brings a consistent dark matter scenario in which the dark photon relic abundance is generated through freeze-in at low reheating temperatures. In addition to its cosmological viability, the model can be tested at the LHC: Higgs bosons can decay into dark photons and displaced visible photons via the long-lived mediator. These signatures allow us to constrain the Higgs portal coupling using recent searches for non-pointing photons and limits on invisible or undetected Higgs decays. We derive meaningful constraints on the dark matter parameter space, in particular excluding a thermalized mediator in the region compatible with the observed relic abundance.

    hep-phastro-ph.COhep-exJHEP(2026)·12 citations
26. 26*

    Characterizing Dark Bosons at Chiral Belle

    Carlos Henrique de Lima🇨🇦 · David McKeen🇨🇦 · Afif Omar🇨🇦 · Douglas Tuckler🇨🇦

    We explore the advantages of a polarized electron beam at Belle II, as proposed for ``Chiral Belle'', in the search for invisibly decaying (dark) bosons that weakly couple to the Standard Model. By measuring the polarization dependence of the production cross section of dark bosons in association with a photon, the dark boson's spin and Lorentz structure of its couplings can potentially be determined. We analyze the mono-photon channel, $e^{+}{e}^{-}\to \gamma +\text{invisible}$, in detail, focusing on the production of an on-shell spin-1 boson. We explore this in the context of three separate scenarios for a new dark vector: a dark photon, a mass-mixed ``dark $Z$'', and a vector that couples to right-handed electrons, and estimate how well the couplings of such bosons to electrons can be constrained in the event of a positive signal.

    hep-phhep-exPRD(2025)·3 citations
27. 27*

    Wino and Real Minimal Dark Matter Excluded by Fermi Gamma-Ray Observations

    Benjamin R. Safdi🇺🇸 · Weishuang Linda Xu🇺🇸

    We show that minimal, fermionic dark matter (DM) models in the $n$-dimensional representation of the weak force with zero hypercharge that make up 100% of the DM under the standard cosmological history are strongly excluded for $n<9$. This includes the thermal wino, which we show is ruled out even allowing for DM core sizes up to $\sim$6.7 kpc with the preferred local DM density or $\sim$3.7 kpc in addition to the local DM density being half the preferred value, at less than $0.2$ GeV/cm${}^3$. We reach these conclusions through dedicated searches with 14 years of Fermi gamma-ray data in the inner Galaxy between 30 GeV and 2 TeV for the continuum gamma-rays produced in the decays of unstable particles produced in DM annihilation and bound-state formation processes. We consider a variety of Milky Way DM profiles in our analyses, including those motivated by modern hydrodynamic cosmological simulations, and show that all the $n<9$ minimal DM models are disfavored even under the most conservative assumptions for these density profiles. While wino, quintuplet ($n=5$), and $n=7$ DM models are strongly disfavored by our analyses under the standard cosmology, we discuss how non-standard cosmological histories or DM sub-fractions could still allow for these particles to be realized in nature, with discovery opportunities at next-generation particle colliders and gamma-ray telescopes.

    hep-phastro-ph.COastro-ph.HE15 citations
28. 28*

    Strong CP from a Hidden Chiral Condensate

    Csaba Csáki🇺🇸 · Samuel Homiller🇺🇸 · Taewook Youn🇺🇸

    Models which solve the strong CP problem by employing discrete spacetime symmetries generically suffer fine-tuning and quality problems. We demonstrate that these issues are greatly ameliorated when the only source of spontaneous CP breaking is from the chiral condensate of a strongly coupled hidden sector. This is shown explicitly in a model with the SM extended by a vector-like quark family and a complex scalar portal to QCD-like dark sector with $N_f$ families of dark fermions that confines at a high scale. The dark pions of the hidden sector are natural dark matter candidates, with the correct relic abundance obtained via freeze-in. These "confining" Nelson-Barr solutions connect phenomenological questions regarding the strong CP problem to recent developments in the understanding of confining gauge theories, and present ample room for further model building.

    hep-phJHEP(2026)·6 citations
29. 29*

    Testing Real WIMPs with CTAO

    Matthew Baumgart🇺🇸 · Salvatore Bottaro🇮🇱 · Diego Redigolo🇮🇹 · Nicholas L. Rodd🇺🇸 · Tracy R. Slatyer🇺🇸

    We forecast the reach of the upcoming Cherenkov Telescope Array Observatory (CTAO) to the full set of real representations within the paradigm of minimal dark matter. We employ effective field theory techniques to compute the annihilation cross section and photon spectrum that results when fermionic dark matter is the neutral component of an arbitrary odd and real representation of SU(2), including the Sommerfeld enhancement, next-to-leading log resummation of the relevant electroweak effects, and the contribution from bound states. We also compute the corresponding signals for scalar dark matter, with the exception of the bound state contribution. Results are presented for all real representations from the $\sim$3 TeV triplet (or wino), a $3$ of SU(2), to the $\sim$300 TeV tredecuplet, a $13$ of SU(2) that is at the threshold of the unitarity bound. Using these results, we forecast that with 500 hrs of Galactic Center observations and assuming background systematics are controlled at the level of $\mathcal{O}(1\%)$, then should no signal emerge, CTAO could exclude all representations up to the $11$ of SU(2) in even the most conservative models for the dark-matter density in the inner galaxy, in both the fermionic and scalar dark matter cases. Assuming the default CTAO configuration, the tredecuplet will marginally escape exclusion, although we outline steps that CTAO could take to test even this scenario. In summary, CTAO appears poised to make a definitive statement on whether real WIMPs constitute the dark matter of our universe.

    hep-phastro-ph.COastro-ph.HEhep-exJHEP(2026)·13 citations
30. 30*

    Extracting Essential Non-perturbative Information in Jet Invariant Mass via the Bayesian Analysis

    Zhan Gao🇨🇳 · Yu Shi🇨🇳 · Bo-Wen Xiao🇨🇳 · Han-Zhong Zhang🇨🇳

    In this paper, we present a new three-dimensional non-perturbative (NP) function to account for and parameterize the NP contributions in the jet invariant mass spectrum, in addition to the conventional NP mass shift parametrization. By implementing Bayesian analysis on experimental data of the jet invariant mass from exclusive $W/Z+$jet events and inclusive jet events in $pp$ collisions at RHIC and LHC, where collisional energy increases by a factor of up to $65$ from RHIC to LHC, we ensure the analysis covers a wide range of data. For the first time, we simultaneously extract NP contributions from hadronization, initial soft-gluon radiation, and underlying events, based on two different NP prescriptions. We find that the contribution from initial soft-gluon radiation is negligible, and the hadronization effect dominates in the small-$R$ region, while underlying events provide the dominant contribution in the large-$R$ region. Moreover, when only hadronization effects are considered, our results successfully describe the jet mass data measured in $e^{+}{e}^{-}$ collisions, where only hadronization effects are expected to be present. Our work offers quantitative insights into understanding the soft hadronic contribution to jet substructure.

    hep-phhep-exhep-thnucl-th1 citation
31. 31*

    Three-loop corrections to the Fermi decay constant in the $\overline{\mathrm{MS}}$ scheme

    Stephen P. Martin🇺🇸

    I present the leading 3-loop contributions to the Fermi decay constant in the Standard Model, using the tadpole-free pure $\overline{\mathrm{MS}}$ scheme. The calculation is exact in the limit in which the QCD coupling, the top-quark Yukawa coupling, and the square root of the Higgs self-coupling are all treated as large compared to the electroweak gauge couplings. The effect of the 3-loop contribution is to decrease the estimate of the Higgs VEV, for fixed on-shell inputs, by about 3.5 MeV. The renormalization scale dependence of the computed Fermi constant is greatly reduced compared to the previously known complete 2-loop order result, and as a fraction is now less than $\pm 2\times 10^{-6}$ for renormalization scales between 90 and 250 GeV. This corresponds to a theoretical uncertainty in the VEV that is well under 1 MeV, and much smaller than the current parametric uncertainties coming mostly from the top-quark mass. I also comment on the impact on the precise prediction of the $W$-boson mass.

    hep-phPRD(2025)·3 citations
32. 32*

    A critical appraisal of tests of locality and of entanglement versus non-entanglement at colliders

    Philip Bechtle🇩🇪 · Cedric Breuning🇩🇪 · Herbi K. Dreiner🇩🇪 · Claude Duhr🇩🇪

    It has been argued more than 30 years ago that it is not possible to test locality at colliders, due to the inability to directly measure non-commutating observables such as spin components in current collider experiments. Recently, there has been a lot of phenomenological and experimental activity around testing locality via Bell-type experiments or entanglement versus non-entanglement in a collider environment. These results seem to evade the earlier no-go theorem by indirectly measuring spin correlations via their relation to angular correlations between momenta. We perform a careful study of the feasibility of such an approach. We scrutinize the relationship between spin and angular correlations in both quantum mechanics and local hidden variable theories. Our conclusion is that it is currently not possible to perform a logically coherent set of experimental measurements at colliders that would allow one to test locality or entanglement versus non-entanglement. This reaffirms the earlier no-go theorem. We stress that the no-go theorem does not apply to measurements of observables inspired from entanglement and Quantum Information Theory to test the Standard Model of particle physics.

    hep-phhep-exquant-ph36 citations
33. 33*

    Colliders are not Testing Locality via Bell's Inequality nor Providing an Unconditional Proof of Entanglement

    Steven A. Abel🇬🇧 · Herbi K. Dreiner🇩🇪 · Rhitaja Sengupta🇩🇪 · Lorenzo Ubaldi🇸🇮

    Recently there has been an increased interest in possible tests of locality via Bell's inequalities, as well as separately tests of entanglement at colliders, in particular at the LHC. These have involved various physical processes, such as $t\bar{t}$, or ${\tau }^{+}{\tau }^{-}$ production, or the decay of a Higgs boson to two vector bosons $H\to V{V}^{\ast }$. We argue that $\text{none}$ of these proposals constitute a test of locality via Bell's inequality or promise unconditional observational evidence of entanglement. In all cases what is measured are the momenta of the final state particles. Using the construction proposed by Kasday (1971) in a different context, and adapted to collider scenarios by Abel, Dittmar, and Dreiner (1992), it is straightforward to construct a local hidden variable theory (LHVT) which exactly reproduces the data. This construction is only possible as the final state momenta all commute. We show that this LHVT satisfies Bell's inequality or the related CHSH inequality as appropriate for all the proposed LHC collider tests in the literature. Thus a test of locality via Bell's inequality is not possible at colliders. The LHVT is also by construction local, $\text{i.e.}$ all correlations are separable. Thus an unconditional proof of entanglement is also inherently $\text{not}$ possible at colliders. It can only be shown that the entanglement within the Standard Model consistently describes the data.

    hep-phhep-exquant-phJHEP(2026)·39 citations
34. 34*

    Distinguishing Neutron Star vs. Low-Mass Black Hole Binaries with Late Inspiral & Postmerger Gravitational Waves $-$ Sensitivity to Transmuted Black Holes and Non-Annihilating Dark Matter

    Sulagna Bhattacharya🇮🇳 · Shasvath Kapadia🇮🇳 · Basudeb Dasgupta🇮🇳

    Gravitational wave signals from binary neutron star (BNS) mergers and binary low-mass black hole (BLMBH) mergers are highly similar in the early inspiral phase. Consequently, the astrophysical origin of recently detected low-mass compact binary coalescences has remained ambiguous, particularly in the absence of electromagnetic counterparts. In this work, we demonstrate that proposed detectors with increased high-frequency sensitivity $-$ including NEMO, Cosmic Explorer, and the Einstein Telescope $-$ will reliably distinguish these two source classes in the late inspiral and postmerger regimes. We further show how these detections can be used to disentangle the individual contributions of BNS and BLMBH systems to the compact binary merger rate, while accounting for misclassification probabilities. Finally, we show this can lead to constraints on the interaction of heavy, non-annihilating dark matter with nucleons. This is achieved by noting that capture of such dark matter particles into neutron stars would lead to transmuted black holes (TBHs), formed via neutron star collapse, which would contribute to the BLMBH rate.

    hep-phastro-ph.COastro-ph.HEJCAP(2026)·7 citations
35. 35*

    Quantifying EFT Uncertainties in LHC Searches

    Spencer Chang🇺🇸 · Markus A. Luty🇺🇸 · Teng Ma🇨🇳 · Francesco Montagno🇪🇸 · Andrea Wulzer🇪🇸

    Effective Field Theory (EFT) is a general framework to parametrize the low-energy approximation to a UV model that is widely used in model-independent searches for new physics. The use of EFTs at the LHC can suffer from a 'validity' issue, since new physics amplitudes often grow with energy and the kinematic regions with the most sensitivity to new physics have the largest theoretical uncertainties. We propose a method to account for these uncertainties with the aim of producing robust model-independent results with a well-defined statistical interpretation. In this approach, one must specify the new operators being studied as well as the new physics cutoff $M$, the energy scale where the EFT approximation breaks down. At energies below $M$, the EFT uncertainties are accounted for by adding additional higher dimensional operators with coefficients that are treated as nuisance parameters. The size of the nuisances are governed by a prior likelihood function that incorporates information about dimensional analysis, naturalness, and the scale $M$. At energies above $M$, our method incorporates the lack of predictivity of the EFT, and we show that this is crucial to obtain consistent results. We perform a number of tests of this method in a simple toy model, illustrating its performance in analyses aimed at new physics exclusion as well as for discovery. The method is conveniently implemented by the technique of event reweighting and is easily ported to realistic LHC analyses. We find that the procedure converges quickly with the number of nuisance parameters and is conservative when compared to UV models. The paper gives a precise meaning and offers a principled and practical solution to the widely debated 'EFT validity issue'.

    hep-phhep-exJHEP(2026)·5 citations
36. 36*

    Sub-GeV Dark Matter Under Pressure from Direct Detection

    Andrew Cheek🇨🇳 · Pablo Figueroa🇪🇸 · Gonzalo Herrera🇺🇸 · Ian M. Shoemaker🇺🇸

    The DAMIC-M collaboration recently reported impressive bounds on sub-GeV dark matter, robustly testing both thermal and non-thermal models for the very first time. In this work we derive novel bounds from the recent PandaX-4T ionization S2-only search for Coherent Elastic Neutrino-Nucleus Scattering (CE$\nu$NS). We find that the PandaX-4T S2-only data is able to compete with the DAMIC-M results, providing the best constraints for scalar and asymmetric thermal dark matter models for masses between 20 to 200 MeV. We further discuss the implications of recent direct detection results for several other sub-GeV dark matter models, highlighting their complementarity with astrophysical, cosmological and laboratory probes.

    hep-phastro-ph.COhep-ex20 citations
37. 37*

    Sources of Radial Flow Fluctuations in the Quark-Gluon Plasma

    Jiangyong Jia🇺🇸

    The differential radial flow fluctuation $v_0(p_{\mathrm{T}})$ has emerged as a new probe of the quark-gluon plasma. However, its characteristic rise-and-fall pattern with $p_{\mathrm{T}}$, resembling anisotropic flow, remains unexplained. I introduce a momentum rescaling framework that factorizes $v_0(p_{\mathrm{T}})$ into kinematic and dynamical components: $v_0(p_{\mathrm{T}})/v_0=-[d\ln ⟨n(p_{\mathrm{T}})⟩/d\ln p_{\mathrm{T}}+1]\times g(p_{\mathrm{T}})$. The first factor, determined by spectral shape, generates the rise-and-fall pattern as the spectra transition from exponential to power-law behavior. The dynamical component $g(p_{\mathrm{T}})$ isolates $p_{\mathrm{T}}$-dependent dynamics: $<1$ signals suppressed fluctuations, $>1$ indicates enhancement. Analysis of LHC data reveals $g(p_{\mathrm{T}})$ deviates from unity by 20-40% in central collisions. Predictions for RHIC show that spectral shape alone generates the rise-and-fall baseline pattern with substantial energy dependence. This framework enables tighter medium property constraints by separating kinematic from dynamical effects, with broad applications to anisotropic flow and higher-order radial flow fluctuations.

    ↳ nucl-thhep-phnucl-exPRL(2026)·11 citations
38. 38*

    Smooth binary evolution from wide resonances in boson clouds

    Giovanni Maria Tomaselli🇺🇸

    Ultralight scalars can form superradiant clouds around rotating black holes. These may alter the dynamics of compact binaries and the ensuing waveform through orbital resonances and cloud ionization. We re-examine resonances involving states with nonzero decay width, deriving an effective treatment for resonances that are wider than the binary's frequency chirp. We demonstrate the utility of this approach by calculating an upper bound for the cloud's mass surviving up to the latest stages of the inspiral. Next, we study the accumulation of resonances with high-energy bound states. When these infinitely many, increasingly weak resonances are properly taken into account, they smooth out the "sharp features" in the binary's evolution that had been attributed to the ionization of the cloud. We compare our Newtonian results with recent relativistic calculations, highlighting common features as well as discrepancies. Our conclusions emphasize the need to carefully incorporate resonances in boson cloud waveform modeling.

    ↳ gr-qcastro-ph.COastro-ph.HEhep-ph+1PRD(2025)·18 citations
39. 39*

    Radiation Spectrum of the Photospheric Emission for a Turbulent Relativistic Jet

    Guo-Yu Li🇨🇳 · Da-Bin Lin🇨🇳 · Zhi-Lin Chen🇨🇳 · En-Wei Liang🇨🇳

    The prompt $\gamma$-rays of gamma-ray bursts (GRBs) may originate from the photosphere of a relativistic jet. However, only a few GRBs have been observed with evident blackbody-like emission, for example, GRB~090902B. It has been demonstrated that internal dissipation processes, such as magnetic reconnection, can occur within the relativistic jet and thereby drive violent turbulence in the dissipation region. In this paper, we study the photospheric emission of a jet with turbulence below its photosphere. Here, the turbulence is modeled phenomenological under the assumption that the four-velocity of its eddies follows a Gaussian distribution in the jet's co-moving frame. It is found that the turbulence scatters photons to high energies and thus intensifies the emission in the high-energy regime. The corresponding distortion of the radiation field can be preserved if and only if the turbulence occurs in a region with incomplete photon-electron coupling. Consequently, the observed radiation spectrum can be reshaped into a Band-like spectrum.

    ↳ astro-ph.HEhep-phApJ(2025)·0 citations
40. 40*

    Opportunities and challenges to study solar neutrinos with a Q-Pix pixel readout

    M. Á. García-Peris🇬🇧 · G. Ruiz🇬🇧 · S. Kubota🇬🇧 · A. Navrer-Agasson🇬🇧 · G. V. Stenico🇬🇧 · E. Gramellini🇬🇧 · R. Guenette🇬🇧 · J. Asaadi🇺🇸 · J.B.R. Battat🇺🇸 · V. A. Chirayath🇺🇸 · E. Church🇺🇸 · Z. Djurcic🇺🇸 and 15 other authors

    The study of solar neutrinos presents significant opportunities in astrophysics, nuclear physics, and particle physics. However, the low-energy nature of these neutrinos introduces considerable challenges to isolate them from background events, requiring detectors with low-energy threshold, high spatial and energy resolutions, and low data rate. We present the study of solar neutrinos with a kiloton-scale liquid argon detector located underground, instrumented with a pixel readout using the Q-Pix technology. We explore the potential of using volume fiducialization, directional topological information, light signal coincidence and pulse-shape discrimination to enhance solar neutrino sensitivity. We find that discriminating neutrino signals below 5 MeV is very difficult. However, we show that these methods are useful for the detection of solar neutrinos when external backgrounds are sufficiently understood and when the detector is built using low-background techniques. When building a workable background model for this study, we identify {\gamma} background from the cavern walls and from capture of {\alpha} particles in radon decay chains as both critical to solar neutrino sensitivity and significantly underconstrained by existing measurements. Finally, we highlight that the main advantage of the use of Q-Pix for solar neutrino studies lies in its ability to enable the continuous readout of all low-energy events with minimal data rates and manageable storage for further offline analyses.

    ↳ hep-exastro-ph.IMastro-ph.SRhep-ph+1PRD(2025)·3 citations
41. 41*

    TASI/CERN/KITP Lecture Notes on "Toward Quantum Computing Gauge Theories of Nature"

    Zohreh Davoudi🇺🇸

    A hallmark of the computational campaign in nuclear and particle physics is the lattice-gauge-theory program. It continues to enable theoretical predictions for a range of phenomena in nature from the underlying Standard Model. The emergence of a new computational paradigm based on quantum computing, therefore, can introduce further advances in this program. In particular, it is believed that quantum computing will make possible first-principles studies of matter at extreme densities, and in and out of equilibrium, hence improving our theoretical description of early universe, astrophysical environments, and high-energy particle collisions. Developing and advancing a quantum-computing based lattice-gauge-theory program, therefore, is a vibrant and fast-moving area of research in theoretical nuclear and particle physics. These lecture notes introduce the topic of quantum computing lattice gauge theories in a pedagogical manner, with an emphasis on theoretical and algorithmic aspects of the program, and on the most common approaches and practices, to keep the presentation focused and useful. Hamiltonian formulation of lattice gauge theories is introduced within the Kogut-Susskind framework, the notion of Hilbert space and physical states is discussed, and some elementary numerical methods for performing Hamiltonian simulations are discussed. Quantum-simulation preliminaries and digital quantum-computing basics are presented, which set the stage for concrete examples of gauge-theory quantum-circuit design and resource analysis. A step-by-step analysis is provided for a simpler Abelian gauge theory, and an overview of our current understanding of the quantum-computing cost of quantum chromodynamics is presented in the end. Examples and exercises augment the material, and reinforce the concepts and methods introduced throughout.

    ↳ hep-lathep-phnucl-thquant-ph19 citations
42. 42*

    Systematic Improvement of Hamiltonian Truncation Effective Theory

    Ekrem Demiray🇺🇸 · Kara Farnsworth🇨🇭 · Rachel Houtz🇺🇸

    Hamiltonian Truncation Effective Theory is a framework that aims to improve the results of Hamiltonian truncation in a systematic, order-by-order fashion using Effective Field Theory methodology. The result is a truncated effective Hamiltonian with corrections that result from a matching procedure. We establish the rigor of this method by calculating nontrival next-to-leading order corrections in a $1/E_{\max }$ expansion, where $E_{\max }$ is our effective theory cutoff. We illustrate this explicitly using 1+1D $\lambda {\varphi }^4$ theory, calculating corrections up to order $1/E_{\max }^3$. At this order, novel nonlocal contributions to the matching conditions must be incorporated. We show that by including these nonlocal terms, the error scales as $1/E_{\max }^4$, as expected from the Effective Field Theory power counting, providing a nontrivial check that this method is consistent and robust. We also estimate the critical coupling at which this theory flows to the 2D Ising conformal field theory and confirm that separation of scales, an essential feature of Effective Field Theory, persists at this order. These results establish Hamiltonian Truncation Effective Theory as a generic, systematic framework for improving convergence in Hamiltonian truncation and lay the groundwork to apply this method to more complex systems in higher dimensions.

    ↳ hep-thcond-mat.str-elhep-lathep-ph5 citations
43. 43*

    Pair production of massive charged vector bosons from the worldline

    Fiorenzo Bastianelli🇮🇹 · Filippo Fecit🇮🇹 · Alessandro Miccichè🇮🇹

    We investigate a worldline formulation for a massive spin-1 particle interacting with an electromagnetic background. Two first-quantized descriptions of the spin degrees of freedom are considered: one based on bosonic oscillators and the other on fermionic oscillators. Focusing initially on the bosonic model -- which can accommodate particles of arbitrary integer spin -- we review how quantization in the spin-1 sector, performed both via Dirac's method and BRST quantization, reproduces the free Proca field theory. We then introduce coupling to an external electromagnetic field and demonstrate that Maxwell's equations for the background emerge as a consistency condition for the nilpotency of the BRST charge on the spin-1 sector. Encouraged by this result, which proves the viability of the particle model, we proceed to construct a path integral quantization of the worldline action for the charged spin-1 particle on the circle. This yields the one-loop effective Lagrangian for a constant electromagnetic field induced by a massive charged vector boson. As expected, the result reveals a vacuum instability, which we quantify by deriving the pair production rate for the vector bosons, recovering previous results obtained in quantum field theory. For comparison, we repeat the analysis using the standard $\mathcal{N}=2$ spinning particle model, which contains fermionic worldline degrees of freedom, finding identical results. Finally, we comment on possible extensions of the worldline models to include effective interactions and briefly explore their implications for pair production.

    ↳ hep-thhep-phJHEP(2025)·7 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.