Fri·Aug 2, 2024Friday·August 2, 2024

1. 01*

   Non-perturbative Origin of Electroweak Scale via Higgs-portal: Dyson-Schwinger in Conformally Invariant Scalar Sector

   Marco Frasca🇮🇹 · Anish Ghoshal🇵🇱 · Nobuchika Okada🇺🇸

   We investigate conformally extended Standard Model with a hidden scalar $\varphi$. It is shown that due to non-perturbative dynamics in the hidden sector, $\varphi$ develops a vacuum expectation value (vev) in the form of a mass gap which triggers the electroweak symmetry breaking (EWSB) and dynamically generates the SM Higgs boson mass. For estimating the non-perturbatively generated mass scale, we solve the hierarchy of Dyson-Schwinger Equations in form of partial differential equations using the exact solution known via a novel technique developed by Bender, Milton and Savage. We employ Jacobi Elliptic function as exact background solution and show that the mass gap that arises in the hidden sector can be transmuted to the EW sector, expressed in terms of Higgs-portal mixed quartic coupling $\beta$ and self interaction quartic coupling ${\lambda }_{\varphi }$ of $\varphi$. We identify the suitable parameter space where the observed SM Higgs boson can be successfully generated . Finally, we discuss how this idea of non-perturbative EW scale generation can serve as a new starting point for better realistic model building in the context of resolving the hierarchy problem in the Standard Model.

   hep-phhep-thFortsch.Phys.(2025)·3 citations
2. 02*

   AI for Nuclear Physics: the EXCLAIM project

   Simonetta Liuti · Douglas Adams · Marie Boër · Gia-Wei Chern · Marija Cuic · Michael Engelhardt · Gary R. Goldstein Brandon Kriesten · Yaohang Li · Huey-Wen Lin · Matt Sievert · Dennis Sivers

   In overview of the recent activity of the newly funded EXCLusives with AI and Machine learning (EXCLAIM) collaboration is presented. The main goal of the collaboration is to develop a framework to implement AI and machine learning techniques in problems emerging from the phenomenology of high energy exclusive scattering processes from nucleons and nuclei, maximizing the information that can be extracted from various sets of experimental data, while implementing theoretical constraints from lattice QCD. A specific perspective embraced by EXCLAIM is to use the methods of theoretical physics to understand the working of ML, beyond its standardized applications to physics analyses which most often rely on industrially provided tools, in an automated way.

   hep-phJINST(2025)·7 citations
3. 03*

   Exploring Optimal Sensitivity of Lepton Flavor Violating Effective Couplings at the $e^{+}{e}^{-}$ Colliders

   Sahabub Jahedi🇮🇳 · Abhik Sarkar🇮🇳

   We analyze lepton flavor violation (LFV) using the Standard Model Effective Field Theory (SMEFT) framework at the future lepton colliders. Our focus is on the associated production of tau lepton with electron/muon at the electron-positron ($e^{+}{e}^{-}$) colliders, related to four-Fermi SMEFT effective operators. In accordance with the upper limits on effective couplings from lepton flavor violating tau decays, we conduct a cut-based analysis to achieve sufficient signal significance. We utilize the optimal observable technique (OOT) to estimate the optimal sensitivity of the effective couplings. The impact of electron beam polarization and the interplay of signal and background in enhancing the optimal sensitivity of the effective couplings are discussed in detail. We find that the sensitivity of flavor-violating effective couplings is enhanced by order of one for 3 TeV center-of-mass (CM) energy and 1000 ${\mathrm{fb}}^{-1}$ integrated luminosity at the $e^{+}{e}^{-}$ colliders.

   hep-phPRD(2024)·13 citations
4. 04*

   Multiplicity distributions in the eikonal and the $U$-matrix unitarization schemes

   E. G. S. Luna🇧🇷 · M. G. Ryskin🇷🇺

   The multiplicity distribution of charged particles produced in the central rapidity ($|\eta |<2.5$) region is calculated for the eikonal and the $U$-matrix unitarization schemes using the AGK cutting rules and compared with the ATLAS 13 TeV data. The data favours the eikonal approach.

   hep-phhep-exhep-thPRD(2024)·4 citations
5. 05*

   Non-thermal baryogenesis from MSSM flat direction

   Naoyuki Haba🇯🇵 · Yasuhiro Shimizu🇯🇵 · Yoshihiro Tanabe🇯🇵 · Toshifumi Yamada🇯🇵

   We study an inflection point inflation scenario where a flat direction of the minimal supersymmetric standard model (MSSM) is identified with the inflaton. We focus on the case where the flat direction (inflaton) has non-zero baryon number, and consider a non-thermal baryogenesis scenario where the decay of the inflaton at the reheating directly generates baryon asymmetry of the Universe. Specifically, we consider a udd flat direction that is lifted by a superpotential operator of dimension 6, and show that inflection point inflation with the udd flat direction can be compatible with cosmological observations and can account for the baryon asymmetry of the Universe.

   hep-phastro-ph.CO0 citations
6. 06*

   Mass Mixing between QCD Axions

   Hai-Jun Li🇨🇳 · Yu-Feng Zhou🇨🇳

   We introduce a novel level crossing phenomenon in the mass mixing between the QCD axions, one canonical QCD axion and one $Z_{\mathcal{N}}$ axion. The level crossing can take place at or slightly before the QCD phase transition critical temperature, depending on the ratio of the axion decay constants $\sim 1.69$. The cosmological evolution of the mass eigenvalues in these two scenarios is similar; however, the transition of axion energy density differs significantly. Finally, we estimate the relic density of the QCD axion dark matter in this context. Additionally, this level crossing may have some interesting cosmological implications.

   hep-phastro-ph.COCPC(2025)·8 citations
7. 07*

   Transition properties of Doubly Heavy Baryons

   Kinjal Patel🇮🇳 · Kaushal Thakkar🇮🇳

   In this study, we have investigated the radiative and semileptonic decay of doubly heavy baryons. Our focus is to determine the static and dynamic properties such as ground state masses, magnetic moment, transition magnetic moment, radiative decay and heavy-to-heavy semileptonic decay rates including their corresponding branching fractions. The ground state masses are calculated by solving the six-dimensional hyperradial Schrödinger equation. The magnetic moments and transition magnetic moments for $J^P={\frac{1}{2}}^{+}$ and $J^P={\frac{3}{2}}^{+}$ baryons are also calculated. In addition, radiative M1 decay widths are computed from the transition magnetic moment. We have employed the Isgur-Wise function(IWF) to analyse the semileptonic decay widths of the doubly heavy baryons. The obtained results are compared with other theoretical predictions.

   hep-phInt.J.Theor.Phys.(2025)·7 citations
8. 08*

   An alternative way to decipher the nature of the doubly charmed tetraquark $T_{cc}(3875{)}^{+}$: its antiparticle $T_{\bar{c}\bar{c}}(3875{)}^{-}$ photoproduction off nuclei near threshold

   E. Ya. Paryev🇷🇺

   We study the inclusive photoproduction of $T_{\bar{c}\bar{c}}(3875{)}^{-}$ mesons (which are the antiparticles of the doubly charmed tetraquarks $T_{cc}(3875{)}^{+}$ discovered recently by the LHCb Collaboration) from nuclei in the near-threshold energy region within the nuclear spectral function approach by considering incoherent direct ($\gamma p(n)\to D^{+}(D^0)T_{\bar{c}\bar{c}}(3875{)}^{-}{\Lambda }_c^{+}$) photon--nucleon $T_{\bar{c}\bar{c}}(3875{)}^{-}$ creation processes as well as five possible different scenarios for their internal structure with the main goal of clarifying the possibility to decipher this structure (and, hence, that of $T_{cc}(3875{)}^{+}$) in photoproduction via integral and differential observables. We calculate the absolute and relative excitation functions for $T_{\bar{c}\bar{c}}(3875{)}^{-}$ production off ${}^{12}$C and ${}^{184}$W target nuclei at near-threshold photon beam energies of 30--38 GeV, the absolute differential cross sections for their production off these target nuclei at laboratory polar angles of 0${}^{\circ }$--10${}^{\circ }$ as well as the A and momentum dependences of the relative (transparency ratios) cross sections for $T_{\bar{c}\bar{c}}(3875{)}^{-}$ production at photon energy of 35 GeV within the adopted scenarios for the $T_{\bar{c}\bar{c}}(3875{)}^{-}$ meson intrinsic structure. We demonstrate that the absolute and relative observables considered show a certain sensitivity to these scenarios. Therefore, the measurement of such observables in future experiments at the proposed high-luminosity electron-ion colliders EIC and EicC in the US and China in the near-threshold energy region might shed light on the $T_{cc}(3875{)}^{+}$ internal structure.

   hep-phhep-exnucl-exnucl-thInt.J.Mod.Phys.A(2024)·3 citations
9. 09*

   Hierarchy of CKM matrix elements and implications of unitarity

   Gurjit Kaur🇮🇳 · Gulsheen Ahuja🇮🇳 · Dheeraj Shukla🇮🇳 · Manmohan Gupta🇮🇳

   The hierarchy amongst the CKM matrix elements, highlighted recently by Luo and Xing, has been rigorously revisited using the PDG parameterization incorporating unitarity constraints. Further, we have explored the evaluation of the CP violating parameter \epsilon_k for the 9 possible unitarity ensured equivalent independent parametrizations of CKM matrix. Interestingly, we find that not all of these reproduce the value of parameter \epsilon_k, this being presumably due to the hierarchical nature of the CKM matrix elements. This situation is echoing similar conclusions regarding the evaluation of Jarlskog's rephasing invariant parameter J through unitarity ensured equivalent possibilities.

   hep-phMod.Phys.Lett.A(2025)·1 citation
10. 10*

    Holographic QCD Running Coupling Constant from the Ricci Flow

    Héctor Cancio🇪🇸 · Pere Masjuan🇪🇸

    Through a holographic model of QCD, we present a phenomenological approach to study the running of the strong coupling constant ${\alpha }_s$ in both non-perturbative and perturbative regimes. The renormalization of the metric tensor, driven by the Ricci Flow, and the breaking of conformal and chiral symmetries -- thanks to introducing a double dilaton model and large-$N_c$ corrections -- allow us to relate the existence of an infrared fixed point in the coupling constant with a smooth matching to pQCD well above 2 GeV. This is done through a model with two fit parameters and one matching point. The proposed dilaton model yields linear Regge trajectories and decay constants for scalar, vector, and tensor meson families similar to their experimental counterparts.

    hep-phPRD(2025)·4 citations
11. 11*

    Probing effective operators in single top quark production in association with a lepton-neutrino pair

    Reza Goldouzian🇺🇸 · Michael D. Hildreth🇺🇸

    We study single top quark production in association with a lepton-neutrino pair at the LHC within the framework of the Standard Model Effective Field Theory (SMEFT). We focus on relevant two-quark-two-lepton operators ($O_{lq}^3$, $O_{lequ}^1$, and $O_{lequ}^3$). It is known that these operators have tiny effects on the inclusive cross section of standard model tW production and are thus typically ignored in the SMEFT searches. However, we show that by employing smart observables, such as $m_{T2}$, the pp$\to$t$\ell \nu$ process is significantly sensitive to these operators. We set the most stringent limit on the coupling strength of the $O_{lq}^3$ operator by reinterpreting the results of a search for new phenomena with two opposite-charge leptons, jets and missing transverse momentum at $\sqrt{s}$ = 13 TeV performed by the ATLAS collaboration. The limits derived on the $O_{lequ}^1$ and $O_{lequ}^3$ operators are comparable to those obtained from probing EFT effects in pp$\to$t$\bar{\mathrm{t}}\ell \nu$ and pp$\to$t$\bar{\mathrm{t}}\ell \ell$ processes at the LHC. Consequently, we propose to include the effects of these three operators on the pp$\to$t$\ell \nu$ process in future global SMEFT analyses to increase the sensitivity and to reduce possible degeneracies.

    hep-phPRD(2024)·0 citations
12. 12*

    Fully strange tetraquark resonant states as the cousins of $X(6900)$

    Yao Ma🇨🇳 · Wei-Lin Wu🇨🇳 · Lu Meng🇩🇪 · Yan-Ke Chen🇨🇳 · Shi-Lin Zhu🇨🇳

    We conduct systematic calculations of the S-wave fully strange systems with ``normal" $\left(J^{PC}=0^{++},1^{+-},2^{++}\right)$ and ``exotic" $\left(J^{PC}=0^{+-},1^{++},2^{+-}\right)$ C-parities, which are the strange analogue of the fully charmed tetraquark state $X(6900)$. Within a constituent quark potential model, we employ the Gaussian expansion method to solve the four-body Schrödinger equation and the complex scaling method to identify resonant states. We obtain a series of resonant states and zero-width states in the mass range of 2.7 to 3.3 GeV, with their widths ranging from less than 1 MeV to about 50 MeV. Their rms radii strongly indicate that they are compact tetraquark states. Among these states, the $T_{4s,2^{++}}(2714)$ may be the most likely one to be observed experimentally. We urge the experimental exploration of the $2^{++}$ $ss\bar{s}\bar{s}$ state around 2.7 GeV in the $\varphi \varphi$ channel. Since the lowest S-wave $ss\bar{s}\bar{s}$ state is around 2.7 GeV, the compact P-wave $ss\bar{s}\bar{s}$ states are expected to be heavier. Hence, $\varphi (2170)$ and $X(2370)$ are unlikely to be compact tetraquark states.

    hep-phhep-exhep-latnucl-thPRD(2024)·17 citations
13. 13*

    Hot and Dense QCD Shear Viscosity at (almost) NLO

    Isabella Danhoni🇩🇪 · Guy D. Moore🇩🇪

    The next-to-leading order weak-coupling shear viscosity of QCD was computed 6 years ago. However, these results have never been applied at finite baryon chemical potential $\mu$, even though intermediate-energy heavy ion collisions and merging neutron stars may explore the Quark-Gluon Plasma in a regime where baryon chemical potentials are large. Here, we extend the next-to-leading order shear viscosity calculations to finite $\mu$, and we show that, while the convergence of the weak-coupling expansion is questionable for achievable plasmas, it is somewhat better at $\mu >T$ than at $\mu =0$.

    hep-phhep-thnucl-thJHEP(2024)·9 citations
14. 14*

    Perturbative results of matrix elements of the axial current and their relation with the axial anomaly

    Ignacio Castelli🇺🇸 · Adam Freese🇺🇸 · Cédric Lorcé🇫🇷 · Andreas Metz🇺🇸 · Barbara Pasquini🇮🇹 · Simone Rodini🇩🇪

    In the Standard Model of particle physics, the axial current is not conserved, due both to fermion masses and to the axial anomaly. Using perturbative quantum chromodynamics, we calculate matrix elements of the local and non-local axial current for a gluon target, clarifying their connection with the axial anomaly. In so doing, we also reconsider classic results obtained in the context of the nucleon spin sum rule as well as recent results for off-forward kinematics. An important role is played by the infrared regulator, for which we put a special emphasis on the nonzero quark mass. We highlight cancellations that take place between contributions from the axial anomaly and the quark mass, and we elaborate on the relation of those cancellations with the conservation of angular momentum.

    hep-phPLB(2024)·12 citations
15. 15*

    Linear power corrections to single top production and decay at the LHC in the narrow width approximation

    Sergei Makarov🇩🇪 · Kirill Melnikov🇩🇪 · Paolo Nason🇮🇹 · Melih A. Ozcelik🇫🇷

    We consider top quark production and decay in the narrow width approximation and study if the polarisation effects, that manifest themselves in correlations of angular distributions of particles from top quark decays and final state jets in the production sub-process, are affected by linear power corrections. We find that, in general, the answer to this question is affirmative. We also discuss how these non-perturbative corrections affect polarisation observables used to study single top production at the LHC. Finally, we point out that generic kinematic distributions of leptons from top quark decays are affected by linear power corrections, which may have implications for proposals to extract the top quark mass from such leptonic observables. On the other hand, we demonstrate that the distribution of the ``out-of-collision-plane'' component of the positron momentum is free from linear power corrections, making it an interesting candidate for the top quark mass measurement.

    hep-phJHEP(2024)·4 citations
16. 16*

    The Inevitable Quark Three-Body Force and its Implications for Exotic States

    Sungsik Noh🇰🇷 · Aaron Park🇰🇷 · Hyeongock Yun🇰🇷 · Sungtae Cho🇰🇷 · Su Houng Lee🇰🇷

    Three-body nuclear forces are essential for explaining the properties of light nuclei with a nucleon number greater than three. Building on insights from nuclear physics, we extract the form of quark three-body interactions and demonstrate that these terms are crucial for extending the quark model fit of the meson spectrum to include baryons using the same parameter set. We then discuss the implications of our findings for exotic configurations involving more than three quarks, such as the $T_{cc}$ and ${\chi }_{c1}(3872)$. We find that the quark three-body interactions provide additional repulsion on the order of 10 MeV for the compact configurations of both the $T_{cc}$ and ${\chi }_{c1}(3872)$. This result, combined with previous calculations, strongly suggests that these tetraquark states are molecular rather than compact states.

    hep-phPLB(2025)·8 citations
17. 17*

    Calculating the Total Cherenkov Radiation Emitted by Low Energy Protons in Liquid Argon and Comparing with Argon Scintillation Light at 128 nm

    Hasan R. Rahman🇺🇸

    Neutrino experiments using liquid argon (LAr) detectors estimate the amount of light produced by different types of particles, but only consider scintillation light, at 128 nm, ignoring Cherenkov light contributions. This research aims to theoretically compare these two contributions to the total amount of light produced between ~ 128 - 500 nm for a proton travelling in LAr and explores how to leverage these under-utilized observables for future detector applications. A new theoretical fit of the refractive index of LAr was performed using recent experimental data, which incorporates the physics of anomalous dispersion in the UV resonance for the first time. Using this fit, we integrate the Frank-Tamm (FT) formula to calculate the instantaneous Cherenkov angular distribution and yield of a proton with a given kinetic energy, as well as the integrated distribution and yield over its trajectory. We compare our results with those obtained using two other non-absorptive refractive index fits available in the literature. Because those fits diverge at the resonance, they significantly overestimate the yield.

    hep-phhep-ex2 citations
18. 18*

    Dark Dwarfs: Dark Matter-Powered Sub-Stellar Objects Awaiting Discovery at the Galactic Center

    Djuna Croon🇬🇧 · Jeremy Sakstein🇺🇸 · Juri Smirnov🇬🇧 · Jack Streeter🇬🇧

    We investigate the effects of dark matter annihilation on objects with masses close to the sub-stellar limit, finding that the minimum mass for stable hydrogen burning is larger than the $\sim 0.075M_{\odot }$ value predicted in the Standard Model. Below this limit, cooling brown dwarfs evolve into stable dark matter-powered objects that we name dark dwarfs. The timescale of this transition depends on the ambient dark matter density ${\rho }_{\mathrm{DM}}$ and circular velocity $v_{\mathrm{DM}}$ but is independent of the dark matter mass. We predict a population of dark dwarfs close to the galactic center, where the dark matter density is expected to be ${\rho }_{\mathrm{DM}}\gtrsim 10^3$ GeV/cm${}^3$. At larger galactic radii the dark matter density is too low for these objects to have yet formed within the age of the universe. Dark dwarfs retain their initial lithium-7 in mass ranges where brown/red dwarfs would destroy it, providing a method for detecting them.

    hep-phastro-ph.COastro-ph.GAastro-ph.HE+1JCAP(2025)·6 citations
19. 19*

    Hadron Collider Signatures of Lepton Number Violation in the Type II Seesaw Model

    Patrick D. Bolton🇸🇮 · Jonathan Kriewald🇸🇮 · Miha Nemevšek🇸🇮 · Fabrizio Nesti🇮🇹 · Juan Carlos Vasquez🇺🇸

    We examine the prospect of observing genuine lepton number violating (LNV) signals at hadron colliders in the context of the Type II seesaw mechanism. The model features smoking gun signals involving same-sign di-leptons and jets that may be the primary observable channel in certain regions of the parameter space. The flavour composition of final-state charged leptons in the minimal model is related to the origin of neutrino masses and is correlated with other rare processes, such as neutrinoless double beta decay. We review existing collider limits and provide sensitivity estimates from LNV signals at upcoming runs of the LHC, for zero and non-zero mass splittings between the scalar triplet components.

    hep-phhep-exPRD(2025)·13 citations
20. 20*

    Comments on graviton detection

    Daniel Carney🇺🇸

    It is possible to make a detector which clicks after absorbing a single graviton. Similarly, it is possible to make a gravitational wave detector which can see the quantum noise induced by certain highly squeezed states of the graviton. However, contrary to some recent arguments in the literature, observation of either or both of these signals would not constitute proof or even evidence that the gravitational field is quantized. This is a simple technical statement: a classical gravitational wave can produce the same output data in a detector. Here we explain this result, presented earlier in arXiv:2308.12988, which is a straightforward extension of an ancient argument in quantum optics.

    ↳ gr-qchep-phhep-thquant-ph22 citations
21. 21*

    Prospects for cosmological research with the FAST array: 21-cm intensity mapping survey observation strategies

    Jun-Da Pan🇺🇸 · Peng-Ju Wu🇨🇳 · Guo-Hong Du🇺🇸 · Yichao Li🇺🇸 · Xin Zhang🇺🇸

    Precise cosmological measurements are essential for understanding the evolution of the universe and the nature of dark energy. The Five-hundred-meter Aperture Spherical Telescope (FAST), the most sensitive single-dish radio telescope, has the potential to provide the precise cosmological measurements through neutral hydrogen 21-cm intensity mapping sky survey. This paper primarily explores the potential of technological upgrades for FAST in cosmology. The most crucial upgrade begins with equipping FAST with a wide-band receiver ($0<z<2.5$). This upgrade can enable FAST to achieve higher precision in cosmological parameter estimation than the Square Kilometre Array Phase-1 Mid frequency. On this basis, expanding to a FAST array (FASTA) consisting of six identical FASTs would offer significant improvements in precision compared to FAST. Additionally, compared with the current results from the data combination of cosmic microwave background, baryon acoustic oscillations (optical galaxy surveys), and type Ia supernovae, FASTA can provide comparable constraints. Specifically, for the dark-energy equation-of-state parameters, FASTA can achieve $\sigma (w_0)=0.09$ and $\sigma (w_a)=0.33$.

    ↳ astro-ph.COgr-qchep-phJCAP(2025)·8 citations
22. 22*

    Quasilocal Newtonian limit of general relativity and galactic dynamics

    Marco Galoppo🇳🇿 · Federico Re🇮🇹 · David L. Wiltshire🇳🇿

    We present a new self-consistent perturbative expansion for realistic isolated differentially rotating systems -- disc galaxies. At leading order it is formally equivalent to Ehlers' Newton-Cartan limit, which we reinterpret in terms of quasilocal energy and angular momentum. The self-consistent coupling of these quasilocal terms leads to first-order differences from the conventional Newtonian limit. A modified Poisson equation is obtained, along with modifications to the equations of motion for the effective fluid elements. By fitting to astrophysical data, we show that the phenomenology of collisionless dark matter for disc galaxies can be reproduced. Potential important consequences for gravitational physics on galactic and cosmological scales are briefly discussed.

    ↳ gr-qcastro-ph.COastro-ph.GAhep-phClass.Quant.Grav.(2025)·14 citations
23. 23*

    Effective Potential in Finite Formulation of QFT

    Sander Mooij🇨🇭 · Mikhail Shaposhnikov🇨🇭

    In recent works, we have shown how $n$-point correlation functions in perturbative QFT can be computed without running into intermediate divergences. Here we want to illustrate explicitly that one can calculate the quantum effective potential by the same method. As a main example, we consider a theory with two fields having large and small vacuum expectation values (vev). We show that no fine-tuning between the {\it physical quantities} is needed to keep the hierarchy between the vevs of different fields.

    ↳ hep-thhep-phNPB(2024)·7 citations
24. 24*

    Impact of the phase transition on Quark-Gluon Plasma with an extremely strong magnetic field in holographic QCD

    Xuanmin Cao🇨🇳 · Hui Liu🇨🇳

    We investigate the phase transition within an extremely strong magnetic background field, employing a holographic Quantum Chromodynamics (QCD) model with a focus on entropy and pressure properties. At relatively modest magnetic field strengths, our study discerns a crossover transition between the normal phase and the Quark-Gluon Plasma (QGP) phase as the temperature rises. In contrast, under the influence of an extremely strong magnetic field, a first-order phase transition is observed. A critical point is identified at $(e{B}_c,T_c)\approx (2.8623{\text{GeV}}^2,0.1191\text{GeV})$, which corresponds to a second-order phase transition. This phase structure is found to be in qualitative agreement with lattice simulation predictions reported in [Phys. Rev. D \textbf{105}, 034511 (2022)]. Furthermore, we explore the impact of the magnetic field on the jet quenching parameter across various phases. At zero magnetic field ($eB=0$ ), the normalized jet quenching parameter $\hat{q}/T^3$ exhibits a monotonic increase with temperature. However, in the presence of a magnetic background field, the normalized jet quenching parameters not only display directional anisotropy but also experience a universal enhancement, particularly in the vicinity of the critical temperature region. This observation suggests that the jet quenching parameter could potentially act as an indicator of phase transitions.

    ↳ hep-thhep-phPRD(2025)·11 citations
25. 25*

    Bayesian analysis of (3+1)D relativistic nuclear dynamics with the RHIC beam energy scan data

    Syed Afrid Jahan🇺🇸 · Hendrik Roch🇺🇸 · Chun Shen🇺🇸

    This work presents a Bayesian inference study for relativistic heavy-ion collisions in the Beam Energy Scan program at the Relativistic Heavy-Ion Collider. The theoretical model simulates event-by-event (3+1)D collision dynamics using hydrodynamics and hadronic transport theory. We analyze the model's 20-dimensional posterior distributions obtained using three model emulators with different accuracy and demonstrate the essential role of training an accurate model emulator in the Bayesian analysis. Our analysis provides robust constraints on the Quark-Gluon Plasma's transport properties and various aspects of (3+1)D relativistic nuclear dynamics. By running full model simulations with 100 parameter sets sampled from the posterior distribution, we make predictions for $p_{\mathrm{T}}$-differential observables and estimate their systematic theory uncertainty. A sensitivity analysis is performed to elucidate how individual experimental observables respond to different model parameters, providing useful physics insights into the phenomenological model for heavy-ion collisions.

    ↳ nucl-thhep-phPRC(2024)·35 citations
26. 26*

    Neutron Star Collapse From Accretion: a Probe of Massive Dark Matter Particles

    Ning Liu🇨🇳 · Arvind Kumar Mishra🇨🇳

    We explore the multi-scatter capturing of the massive dark matter (DM) particle inside the neutron star via a momentum-dependent dark matter-nucleon scattering cross-section. We find that the capturing enhanced for the positive velocity and momentum transfer dependent DM-nucleon scattering in comparison with the constant cross-section case. Further, a large capture of the DM particles can be thermalized and lead to black hole formation and, therefore, destroy the neutron star. Using the observation of the old neutron star in the DM-dominated region, we obtain strong constraints on massive DM parameters.

    ↳ astro-ph.COastro-ph.HEgr-qchep-phPhys.Dark Univ.(2025)·11 citations
27. 27*

    Nanohertz gravitational waves from a quasar-based supermassive black hole binary population model as dark sirens

    Si-Ren Xiao🇺🇸 · Yue Shao🇺🇸 · Ling-Feng Wang🇨🇳 · Ji-Yu Song🇺🇸 · Lu Feng🇨🇳 · Jing-Fei Zhang🇺🇸 · Xin Zhang🇨🇳

    Recently, several pulsar timing array (PTA) projects have detected evidence of the existence of a stochastic gravitational wave background (SGWB) in the nanohertz frequency band, providing confidence in detecting individual supermassive black hole binaries (SMBHBs) in the future. Nanohertz GWs emitted by inspiraling SMBHBs encode the luminosity distances of SMBHBs. They can serve as dark sirens to explore the cosmic expansion history via a statistical method to obtain the redshift information of GW sources' host galaxies using galaxy catalogs. The theoretical analysis of the dark siren method relies on the modeling of the population of SMBHBs. Using a population model consistent with the latest SGWB observations is essential, as the SGWB provides significant information about the distribution of SMBHBs. In this work, we employ a quasar-based model, which can self-consistently account for the SGWB amplitude, to estimate the population of SMBHBs. We constrain the Hubble constant using the mock GW data from different detection cases of PTAs in the future. Our results show that a PTA consisting of 100 pulsars with a white noise level of 20 ns could measure the Hubble constant with a precision close to $1\%$ over a 10-year observation period, and a PTA with 200 pulsars may achieve this goal over a 5-year observation period. The results indicate that modeling the SMBHB population significantly influences the analysis of dark sirens, and SMBHB dark sirens have the potential to be developed as a valuable cosmological probe.

    ↳ astro-ph.COgr-qchep-phJCAP(2025)·26 citations
28. 28*

    Subspace-projected multireference covariant density functional theory

    X. Zhang🇨🇳 · C. C. Wang🇨🇳 · C. R. Ding🇨🇳 · J. M. Yao🇨🇳

    Multireference density functional theory (MR-DFT) has been a pivotal method for studying nuclear low-lying states and neutrinoless double-beta ($0\nu \beta \beta$) decay. However, quantifying their theoretical uncertainties has been a significant challenge due to the computational demands. This study introduces a subspace-projected covariant density functional theory (SP-CDFT), which efficiently emulates MR-CDFT calculations for nuclear low-lying states. This approach leverages the eigenvector continuation method combined with the quantum-number projected generator coordinate method, based on a relativistic energy density functional (EDF). We apply SP-CDFT to investigate the correlations among the physical quantities of nuclear matter, nuclear low-lying spectroscopy, and the nuclear matrix elements (NMEs) of $0\nu \beta \beta$ decay in the two heaviest candidate nuclei. Our findings reveal generally strong correlations between the NMEs of $0\nu \beta \beta$ decay and the excitation energy of the $2_1^{+}$ state, as well as the $E2$ transition strength, although these correlations vary significantly among nuclei. This work also paves the way for refining nuclear EDF parameters using spectroscopic data.

    ↳ nucl-thcond-mat.str-elhep-phnucl-exPRC(2025)·10 citations
29. 29*

    The Smile of Cheshire Cat At High Density

    Mannque Rho🇫🇷

    Baryons in finite nuclei, nuclear matter and dense compact-star matter are described in terms of Cheshire Cat for QCD. A potential conceptual link, admittedly short in mathematical rigor, between their manifestations is made by what's called Cheshire Cat Principle. Put in terms taken ``dual" to QCD variables, going to very high density exposes quantum Hall droplets -- or pancakes -- at which the dilaton-limit fixed point with $g_A\to 1$, $f_{\pi }\to f_{\chi }$ -- where $f_{\pi }$ and $f_{\chi }$ are respectively the pion and dilaton decay constants -- and the baryon parity-doubling are reached. This scenario suggests a thus-far totally unexplored structure of dual baryonic matter at high density which does neither require nor rule out (rapid) first-order phase transitions from hadrons to quarks in the core of compact stars on the verge of gravitational collapse.

    ↳ nucl-thhep-phJ.Subatomic Part.Cosmol.(2024)·6 citations
30. 30*

    Free energy from forward scattering in 1+1d

    Daniel Schubring🇺🇸

    The free energy, or equivalently the ground state energy in finite volume, may be calculated from forward scattering amplitudes using a formula due to Dashen, Ma, and Bernstein. However a naive treatment leads to singularities when considering the scattering of three or more particles. It is shown in detail how the approach can be applied to multi-particle scattering in various massive scalar theories in 1+1d, with or without integrability. The results for the sinh-Gordon, Lieb-Liniger, and $O(N)$ non-linear sigma models are compared to exact results. It is shown how bound states can be considered in this approach by considering the attractive Lieb-Liniger model.

    ↳ hep-thhep-phJHEP(2026)·4 citations
31. 31*

    Leveraging Time-Dependent Instrumental Noise for LISA SGWB Analysis

    James Alvey🇳🇱 · Uddipta Bhardwaj🇳🇱 · Valerie Domcke · Mauro Pieroni🇨🇭 · Christoph Weniger🇳🇱

    Variations in the instrumental noise of the Laser Interferometer Space Antenna (LISA) over time are expected as a result of e.g. scheduled satellite operations or unscheduled glitches. We demonstrate that these fluctuations can be leveraged to improve the sensitivity to stochastic gravitational wave backgrounds (SGWBs) compared to the stationary noise scenario. This requires optimal use of data segments with downward noise fluctuations, and thus a data analysis pipeline capable of analysing and combining shorter time segments of mission data. We propose that simulation based inference is well suited for this challenge. In an approximate, but state-of-the-art, modeling setup, we show by comparison with Fisher Information Matrix estimates that the optimal information gain can be achieved in practice.

    ↳ gr-qcastro-ph.COastro-ph.IMhep-phPRD(2025)·17 citations
32. 32*

    On the Generality and Persistence of Cosmological Stasis

    James Halverson🇺🇸 · Sneh Pandya🇺🇸

    Hierarchical decays of $N$ matter species to radiation may balance against Hubble expansion to yield stasis, a new phase of cosmological evolution with constant matter and radiation abundances. We analyze stasis with various machine learning techniques on the full $2N$-dimensional space of decay rates and abundances, which serve as inputs to the system of Boltzmann equations that governs the dynamics. We construct a differentiable Boltzmann solver to maximize the number of stasis $e$-folds $\mathcal{N}$. High-stasis configurations obtained by gradient ascent motivate log-uniform distributions on rates and abundances to accompany power-law distributions of previous works. We demonstrate that random configurations drawn from these families of distributions regularly exhibit many $e$-folds of stasis. We additionally use them as priors in a Bayesian analysis conditioned on stasis, using stochastic variational inference with normalizing flows to model the posterior. All three numerical analyses demonstrate the generality of stasis and point to a new model in which the rates and abundances are exponential in the species index. We show that the exponential model solves the exact stasis equations, is an attractor, and satisfies $\mathcal{N}\propto N$, exhibiting inflation-level $e$-folding with a relatively low number of species. This is contrasted with the $\mathcal{N}\propto \log (N)$ scaling of power-law models. Finally, we discuss implications for the emergent string conjecture and string axiverse.

    ↳ astro-ph.COhep-phhep-thPRD(2024)·13 citations
33. 33*

    Calibrating Bayesian Generative Machine Learning for Bayesiamplification

    Sebastian Bieringer🇩🇪 · Sascha Diefenbacher🇺🇸 · Gregor Kasieczka🇩🇪 · Mathias Trabs🇩🇪

    Recently, combinations of generative and Bayesian machine learning have been introduced in particle physics for both fast detector simulation and inference tasks. These neural networks aim to quantify the uncertainty on the generated distribution originating from limited training statistics. The interpretation of a distribution-wide uncertainty however remains ill-defined. We show a clear scheme for quantifying the calibration of Bayesian generative machine learning models. For a Continuous Normalizing Flow applied to a low-dimensional toy example, we evaluate the calibration of Bayesian uncertainties from either a mean-field Gaussian weight posterior, or Monte Carlo sampling network weights, to gauge their behaviour on unsteady distribution edges. Well calibrated uncertainties can then be used to roughly estimate the number of uncorrelated truth samples that are equivalent to the generated sample and clearly indicate data amplification for smooth features of the distribution.

    ↳ cs.LGcs.AIhep-phMach.Learn.Sci.Tech.·19 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.