Fri·Feb 28, 2025Friday·February 28, 2025

1. 01*

   Dynamical $\mathbf{O}(4)$-Symmetry in the Light Meson Spectrum within the Framework of the Regge Approach

   Sergey Afonin🇷🇺 · Alisa Tsymbal🇷🇺

   The light mesons tend to cluster near certain values of mass. As was noticed almost twenty years ago, the emergent degeneracy is of the same type as the dynamical $O(4)$-symmetry of the Coulomb potential in the hydrogen atom. The meson mass spectrum can be well approximated by the linear Regge trajectories of the kind $M^2=al+b{n}_r+c$, where $l$ and $n_r$ are angular momentum and radial quantum numbers and $a$, $b$, $c$ are parameters. Such a spectrum arises naturally within the hadron string models. Using 2024 data from the Particle Data Group, various fits for $M^2(l,n_r)$ were performed. Our analysis seems to confirm that $a\approx b$ in the light non-strange mesons, i.e., their masses depend on the sum $l+n_r$ as prescribed by the hydrogen-like $O(4)$-symmetry. Using the semiclassical approximation, we discuss on a simple qualitative level which kind of string-like semirelativistic approaches are more favored by the experimental data.

   hep-phPhys.Atom.Nucl.(2024)·5 citations
2. 02*

   Extension of SUSY SU(5) GUTs with Nelson-Barr models

   Junji Hisano🇯🇵 · Moe Kuroda🇯🇵

   In this paper we extend the supersymmetric SU(5) GUTs with the Nelson-Barr (NB) models. The NB models are a candidate for the solution of the strong CP problem. We show that the parameters in the CKM matrix are reproduced while the mass ratios of the down-type quarks and leptons in the second and third generations are explained in the minimal extension.

   hep-phJHEP(2025)·1 citation
3. 03*

   Effective range expansion with the left-hand cut and its application to the $T_{cc}(3875)$

   Meng-Lin Du🇨🇳 · Feng-Kun Guo🇨🇳 · Bing Wu🇨🇳

   The validity range of the widely used traditional effective range expansion can be severely limited by the presence of a left-hand cut near the two-particle threshold. Such a left-hand cut emerges in two-particle scattering processes involving either a light particle exchange in the $t$-channel or a particle exchange with a mass slightly heavier than the mass difference of the two particles in the $u$-channel, which occurs in a wide range of physical systems. We propose a new parameterization for the low-energy scattering amplitude that incorporates these left-hand cuts arising from particle exchange diagrams. This parameterization extends the convergence radius of the effective range expansion beyond the branch point of the left-hand cut and is applicable to a broad range of systems. The parameterization enables the extraction of coupling strengths between the exchange particle and the scattering particles, and reveals amplitude zeros resulting from the interplay between short- and long-range interactions. We demonstrate the effectiveness of this new parameterization through its application to $D{D}^{\ast }$ scattering with meson masses obtained in a lattice QCD calculation.

   hep-phPoS(2026)·7 citations
4. 04*

   Next-to-leading order QCD corrections to $B_c^{\ast }\to J/\psi$ form factors

   Qin Chang🇨🇳 · Wei Tao🇨🇳 · Zhen-Jun Xiao🇨🇳 · Ruilin Zhu🇨🇳

   Within the framework of Non-Relativistic Quantum Chromodynamics (NRQCD) factorization, we calculate the next-to-leading order (NLO) perturbative QCD corrections to the form factors for the semileptonic decays of $B_c^{\ast }$ into $J/\psi$ via (axial-)vector and (axial-)tensor currents. We obtain the complete analytical results for the form factors up to NLO, and provide their asymptotic expressions in the hierarchical heavy quark limit. The NLO corrections are found to be both significant and convergent in the relatively small squared transfer momentum ($q^2$) region, while also reducing the dependence on the renormalization scale $\mu$. Finally, the theoretical predictions for $B_c^{\ast }\to J/\psi$ form factors over the full $q^2$ range are provided.

   hep-phPRD(2025)·1 citation
5. 05*

   Radiative decays of $X(3872)$ in $D{\bar{D}}^{\ast }$ molecule scenario

   Fan Wang🇨🇳 · Gang Li🇨🇳 · Shi-Dong Liu🇨🇳 · Qi Wu🇨🇳

   We investigate the radiative decays of the $X(3872)$ to $\gamma V(V={\rho }^0,\omega )$ in the molecule scenario, where the $X(3872)$ is regarded as a pure hadronic molecule of the $D{\bar{D}}^{\ast }+c.c$ in an $S$-wave with the quantum numbers $J^{PC}=1^{++}$. The radiative processes were assumed to occur via the triangle hadronic loops, and the relevant calculations were conducted using an effective Lagrangian approach. It is found that the absolute decay widths are model-dependent, but the relative width ratio is rather independent of the model parameter. Moreover, the calculated results indicate that the radiative decays of the $X(3872)$ are strongly influenced by the molecular configuration characterized by the proportion of the charged and neutral constituents. We hope that the present calculations could be tested by the experimental measurements.

   hep-phPRD(2025)·6 citations
6. 06*

   The canonical differential equations of the one-loop-like integrals

   Jiaqi Chen🇨🇳 · Bo Feng🇨🇳 · Liang Zhang🇨🇳

   Recently, a new approach for high loop integrals has been proposed in \cite{Huang:2024nij}, where the whole parameter integration has been divided into two parts: a one-loop-like integration and the remaining parameter integration. In this paper, we systematically study the one-loop-like integrals. We establish the IBP relations for the integral family and show how to complete the reduction. We find the canonical master integrals and write down the corresponding canonical differential equations.

   hep-phJHEP(2025)·1 citation
7. 07*

   Short-distance contributions to Hadronic-light-by-light for the muon $g-2$

   Johan Bijnens (Lund)🇸🇪 · Nils Hermansson-Truedsson (Lund, Edinburgh)🇸🇪 · Antonio Rodríguez-Sánchez (Valencia)🇪🇸

   This talk discusses short-distance contributions to the hadronic light-by-light part of the muon g-2 as in the Standard Model. A short discussion about the theory prediction is followed by the status of our work. The main new results since the previous chiral dynamics workshop is how to calculate the higher order corrections to the Melnikov-Vainshtein region using the operator product expansion. We work out fully the next order in the OPE, $D=4$, including photon and gluon only operators. In addition we briefly discuss the ongoing work on gluonic corrections to the next-order and nonperturbative estimates.

   hep-phPoS(2026)·0 citations
8. 08*

   Probing light mediators with recent PandaX-4T low energy electron recoil data

   Mehmet Demirci🇹🇷 · M. Fauzi Mustamin🇹🇷

   Neutrinos elastically scattered off atomic electrons offer a unique opportunity to probe the Standard Model (SM) and beyond SM physics. In this work, we examine the new physics effects of light mediators through elastic neutrino-electron scattering using solar neutrinos at the low energy range of PandaX-4T. These mediators, with a mass less than $1$ GeV, are common properties of extensions to the SM. Accordingly, we consider universal light mediator models involving scalar, vector, and tensor interactions allowed by Lorentz invariance, and the anomaly-free $U(1{)}^{\prime }$ extensions of the SM with a new vector mediator such as the $L_e-L_{\mu }$, $L_e-L_{\tau }$ and $L_{\mu }-L_{\tau }$ gauge models in which the charges are exclusively leptonic. The new physics effects are analyzed by embedding each model into the SM process using solar neutrino flux. We obtain novel constraints on the coupling-mass plane of these models from the latest Run0 and Run1 datasets of the PandaX-4T experiment. We also compare our results with other limits derived from various terrestrial and astrophysical experiments. Our analysis results reveal more stringent limits in some regions of parameter space.

   hep-phPRD(2025)·10 citations
9. 09*

   Spin 1 Transverse Momentum Dependent Tensor Structure Functions in CLAS12

   Jiwan Poudel🇺🇸 · Alessandro Bacchetta🇮🇹 · Jian-Ping Chen🇺🇸 · Dustin Keller🇺🇸 · Ishara Fernando · Elena Long🇺🇸 · David Ruth🇺🇸 · Nathaly Santiesteban🇺🇸 · Karl Slifer🇺🇸

   We propose to analyze CLAS12 RG-C data to study the tensor transverse-momentum-dependent parton distribution functions (TMDs) on deuteron data. The deuteron is the lightest nucleus with spin-1, in essence a weakly bound system of two spin-1/2 nucleons. However, one of the most intriguing characteristics of the deuteron is that the tensor polarized structure provides direct access to the quark and gluon distribution of light nuclear system, which cannot be naively constructed from the proton and neutron. We will study the tensor polarized structure functions with the Semi-inclusive Deep Inelastic Scattering (SIDIS) $eD\text{arrow}e{P}_{h}X$ and Inclusive processes in the available data on deuterated ammonia (ND3) target. We will perform the first ever SIDIS analysis extraction of the tensor structure functions, which can be interpreted in term of completely unexplored tensor polarized TMDs. Our analysis will focus on the extraction of the tensor structure functions b1 from inclusive process, and $F_{U(LL),T}$ and $F_{U(LL)}^{cos2{\varphi }_h}$ from SIDIS. These last two structure functions carry information related to two tensor-polarized TMDs, $f_{1LL}$ and $h_{1LL}^{\perp }$. These initial exploratory measurements of tensor-polarized structure functions will enable the first extraction of spin-1 TMDs and motivate more precise future measurements.

   hep-phhep-ex7 citations
10. 10*

    Planar Property and Long-range Azimuthal Correlation in $e^{+}{e}^{-}$ Annihilation

    Xuan Chen🇨🇳 · Yuesheng Dai🇨🇳 · Shi-Yuan Li🇨🇳 · Zong-Guo Si🇨🇳 · Huiting Sun🇨🇳

    The $e^{+}{e}^{-}$ annihilation of unpolarized beams is free from initial hadron states or initial anisotropy around the azimuthal angle, hence ideal for studying the correlations of dynamical origin via final state jets. We investigate the planar properties of the multi-jet events employing the relevant event-shape observables at next-to-next-to-leading order ($\mathcal{O}$(${\alpha }_s^3$)) in perturbative QCD; particularly, the azimuthal angle correlations on the long pseudo-rapidity (polar angle) range (Ridge correlation) between the inclusive jet momenta are calculated. We illustrate the significant planar properties and the strong correlations which are natural results of the energy-momentum conservation of the perturbative QCD radiation dynamics. Our study provides benchmarks of hard strong interaction background for the investigations on the collective and/or thermal effects via the Ridge-like correlation observables for complex scattering processes.

    hep-phCPC(2026)·0 citations
11. 11*

    Constraints on lepton flavor universal and non-universal New Physics in $b\to s{\ell }^{+}{\ell }^{-}$ decays: a global SMEFT survey

    Md Isha Ali🇮🇳 · Utpal Chattopadhyay🇮🇳 · Dilip Kumar Ghosh🇮🇳 · N Rajeev🇮🇳

    The flavor-changing neutral current semileptonic decays of $B$ mesons provide an excellent platform for indirectly probing New Physics (NP) beyond the Standard Model (SM). Recent measurements of lepton flavor universality (LFU) ratios such as $R_K$, $R_{K^{\ast }}$, and $R_{\varphi }$ are consistent with SM predictions, thereby reducing earlier hints of LFU violation. Nevertheless, notable tensions persist in individual branching fractions -- for instance $\mathcal{B}(B^{+}\to K^{+}{\mu }^{+}{\mu }^{-})$ and $\mathcal{B}(B^{+}\to K^{+}{e}^{+}{e}^{-})$, which deviate at the $4\sigma$--$5\sigma$ level in the low-$q^2$ region ($[1.1,6]$ GeV${}^2$). Similarly, the angular observable $P_5^{\prime }$ in $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ shows a $3.3\sigma$ deviation, while $\mathcal{B}(B_s\to \varphi {\mu }^{+}{\mu }^{-})$ departs from the SM by $3.6\sigma$. Although such discrepancies could in principle originate from underestimated hadronic effects, they may also indicate possible NP contributions. In this work, we perform a global fit to the latest $b\to s{\ell }^{+}{\ell }^{-}$ data within the framework of dimension-6 SMEFT operators. Our analysis systematically incorporates hadronic uncertainties from form factors, non-factorizable corrections, and input parameters, thereby providing a balanced assessment of the NP interpretation. We allow for NP contributions not only in $b\to s{\mu }^{+}{\mu }^{-}$ transitions but also in $b\to s{e}^{+}{e}^{-}$ channels, thus testing both lepton flavor universal (LFU) and lepton flavor universality violating (LFUV) NP scenarios. The interplay between these possibilities yields distinctive signatures in branching fractions, angular observables, and $\Delta$-observables, offering a comprehensive view of the current flavor anomalies.

    hep-phhep-exNPB(2026)·8 citations
12. 12*

    Determination of the $K^{+}{\bar{K}}^0$ scattering length and effective range from the $D^{+}\to {\bar{K}}^0{\pi }^{+}\eta$ reaction

    Jing Song🇨🇳 · Wei-Hong Liang🇨🇳 · Eulogio Oset🇪🇸

    We study the scattering parameters of the \(K^+\bar{K}^0\) system through the analysis of the \(D^+\to\bar{K}^0\pi^+\eta\) reaction, aiming at determining the scattering length \(a\) and effective range \(r_0\) of the \(K^+\bar{K}^0\) interaction. These parameters are extracted by analyzing and fitting the mass distributions of the pairs in the final \(\bar{K}^0\pi^+\eta\) state. To ensure the reliability of the results, we apply resampling techniques to evaluate statistical uncertainties and improve the precision of the scattering parameters. The obtained results are compared with previous theoretical predictions and experimental data, providing new insights into the \(K^+\bar{K}^0\) interaction at low energies.

    hep-phEPJC(2025)·4 citations
13. 13*

    SU(3) analysis of nonfactorizable contributions to bottom mesons decays

    Maninder Kaur🇮🇳 · R. C. Verma🇮🇳

    This paper is the extension of our previous work [arXiv:2108.03296] entitled Searching a systematics for nonfactorizable contributions to B hadronic decays. In order to realize the full impact of isospin analysis, and to relate decays of strange bottom meson with those of nonstrange bottom mesons, we generalize it to the SU(3) flavor symmetry to investigate the nonfactorizable contributions to CKM-enhanced and CKM-suppressed decays. We start with expressing total weak decay amplitude as sum of the factorizable and nonfactorizable parts, then obtain the factorizable part of the decay amplitude numerically using the known meson decay constants and relevant form-factors, then express the nonfactorizable parts in terms of SU(3)-reduced matrix elements. Using measured branching fractions of a few CKM-favored modes, we fix the reduced matrix elements, and predict branching ratios of the remaining CKM-favored decays and all CKM-suppressed B to PP decays processes.We find that the measured branching fractions agree well with our results, and other predicted values may be tested in the future experiments.

    hep-phJ.Subatomic Part.Cosmol.(2025)·2 citations
14. 14*

    Numerical simulations of density perturbation and gravitational wave production from cosmological first-order phase transition

    Jintao Zou🇨🇳 · Zhiqing Zhu🇨🇳 · Zizhuo Zhao🇨🇳 · Ligong Bian🇨🇳

    We conducted three-dimensional lattice simulations to study the density perturbation and gravitational waves (GWs) during first-order phase transition (FOPT). We find that for phase transition strength $\alpha >1$, the forward motion of bubble walls becomes the primary source, whereas for $\alpha <1$, the dominant contribution to the density perturbation comes from the delay of vacuum decay. Additionally, the power spectrum of density perturbations generated by the phase transition exhibits a slope of $k^3$ at small wavenumbers and $k^{-1.5}$ at large wavenumbers. Furthermore, we calculated the GW power spectra, which exhibit the slope of $k^3$ at small wavenumbers and $k^{-2}$ at large wavenumbers. Our numerical simulations confirm that slow PTs can produce PBHs and provide predictions for the GW power spectrum, offering theoretical support for GW detection.

    hep-phastro-ph.COhep-thSCPMA(2026)·13 citations
15. 15*

    QCD Vacuum Energy and Its Implication for Quark Nugget Stability

    Yang Bai🇺🇸 · Ting-Kuo Chen🇺🇸

    In this work, we employ both theoretical and data-driven methods to derive the QCD vacuum energy, utilizing the GMOR relation, the low-energy theorem, and the equation of state from Lattice QCD. The QCD vacuum energy is determined to be between around $(163\text{mbox}MeV{)}^4$ and $(190\text{mbox}MeV{)}^4$. With the assumptions of complete deconfinement, vanishing gluon condensate, full chiral-symmetry restoration, and the validity of perturbative QCD at baryon chemical potentials of order of the proton mass, a very specific kind of quark nugget is found to be less stable than ordinary nuclei.

    hep-phhep-latnucl-thPRD(2026)·8 citations
16. 16*

    Generative adversarial neural networks for simulating neutrino interactions

    Jose L. Bonilla🇵🇱 · Krzysztof M. Graczyk🇵🇱 · Artur M. Ankowski🇵🇱 · Rwik Dharmapal Banerjee🇵🇱 · Beata E. Kowal🇵🇱 · Hemant Prasad🇵🇱 · Jan T. Sobczyk🇵🇱

    We propose a new approach to simulate neutrino scattering events as an alternative to the standard Monte Carlo generator approach. Generative adversarial neural network (GAN) models are developed to simulate charged current neutrino-carbon collisions in the few-GeV energy range. We consider a simplified framework to generate muon kinematic variables, specifically its energy and scattering angle. GAN models are trained on simulation data from \nuwro{} Monte Carlo event generator. Two GAN models have been obtained: one simulating quasielastic neutrino-nucleus scatterings and another simulating all interactions at given neutrino energy. The models work for neutrino energy ranging from 300 MeV to 10 GeV. The performance of both models has been assessed using two statistical metrics. It is shown that both GAN models successfully reproduce the distribution of muon kinematics.

    hep-phcs.LGhep-exnucl-ex+1PRD(2025)·5 citations
17. 17*

    Constraints on Anomalous Quartic Gauge Couplings via Electroweak Production of $\gamma \gamma jj$ at Future Proton-Proton Colliders

    A. Senol🇹🇷 · M. Tekin🇹🇷 · B. S. Ozaltay🇹🇷 · H. Denizli🇹🇷

    The investigation of quartic gauge couplings provides a crucial test of the Standard Model and serves as a potential window into new physics at higher energy scales. Within the framework of Effective Field Theory, deviations from the SM can be parameterized through dimension-8 operators. In this study, we analyze the process $pp\to \gamma \gamma jj$ at the High-Luminosity Large Hadron Collider (HL-LHC) and the Future Circular Collider in hadron mode (FCC-hh) to probe the sensitivity to anomalous quartic gauge couplings (aQGCs), particularly $f_{T8}/{\Lambda }^4$ and $f_{T9}/{\Lambda }^4$. Monte Carlo simulations of signal and relevent backgrouds are performed using MadGraph for event generation, Pythia for parton showering and hadronization, and Delphes for detector simulation. A multivariate analysis based on Boosted Decision Trees is employed to optimize the signal-to-background discrimination, incorporating a comprehensive set of kinematic and reconstructed variables of the final state particles. Additionally, we evaluate unitarity-violating effects associated with dimension-8 operators by imposing energy cutoffs on the di-photon invariant mass. The expected exclusion and discovery significances are computed, accounting for systematic uncertainties to ensure a realistic assessment of collider reach. Our findings indicate that the FCC-hh offers significantly improved sensitivity compared to the HL-LHC and current experimental results by ATLAS, reinforcing its potential for probing aQGCs. Notably, even under a 10\% systematic uncertainty, our projected limits for FCC-hh at 95\% confidence level surpass the current best constraints reported by the ATLAS collaboration, highlighting the enhanced discovery prospects at future high-energy colliders.

    hep-phhep-exJ.Phys.G(2026)·1 citation
18. 18*

    Search for CP Violations in the Production and Decay of the Hyperon-Antihyperon Pairs

    Mengjiao Guo🇨🇳 · Zhe Zhang🇨🇳 · Ronggang Ping🇨🇳 · Jianbin Jiao🇨🇳

    This study introduces a complete joint angular distribution analysis for the process $e^{+}{e}^{-}\to J/\psi \to B(\to B_1\pi )\bar{B}(\to {\bar{B}}_1\pi )$ with polarized beams, where $B$ and $B_1$ are hyperons. We consider both transverse and longitudinal beam polarization and analyze $CP$ violation in the production and decay of hyperons. We present the complete Fisher information matrix for the sensitivities of the weak decay parameters ${\alpha }_{-},{\alpha }_{+},{\varphi }_{\Xi }$ and ${\bar{\varphi }}_{\Xi }$, the $P$-violating term $F_A$, and the EDM $d_B$ (derived from the $CP$-violating term $H_T$), under the BESIII and STCF statistics. We find that polarization enhances the sensitivity of the parameters. Specifically, longitudinal polarization provides a more significant improvement compared to transverse polarization, with the enhancement being more pronounced for single-step decays than for multistep decays. With the expected statistics from the BESIII experiment, the estimated EDM sensitivities for $\Lambda$ and ${\Sigma }^{+}$ are on the order of $10^{-19}e\mathrm{cm}$, while those for ${\Xi }^{-}$ and ${\Xi }^0$ are $10^{-18}e\mathrm{cm}$. The upcoming STCF experiment is expected to improve these estimates by $1-2$ orders of magnitude. Furthermore, $CP$ violation in hyperon decays originates from weak-phase differences among partial-wave amplitudes. Based on a refined isospin analysis, we emphasize the non-negligible contribution of $\Delta I=3/2$ amplitudes to $CP$ violation and advocate for increased theoretical attention to this aspect in future studies..

    hep-phPRD(2026)·6 citations
19. 19*

    Flavor puzzle in three Higgs-doublet models: Insights from BGL and lessons from flavor data

    Dipankar Das🇮🇳 · Miguel Levy🇨🇭 · Anugrah M. Prasad🇮🇳

    We study a variant of the 3HDM, referred to as the BGL-3HDM, incorporating a $U(1{)}_1\times U(1{)}_2$ symmetry, which can distinguish the primary sources of mass for different fermion generations. In the version considered here, the Yukawa matrices in the down-quark and charged lepton sectors are diagonal, thereby eliminating tree-level FCNCs in these sectors. FCNC interactions mediated by neutral nonstandard Higgses are confined to the up-quark sector only. No new BSM parameters are introduced by the Yukawa sector of the model, making it as economical as the NFC versions of 3HDM with a $U(1{)}_1\times U(1{)}_2$ symmetry in terms of the number of free parameters. However, even in the down-quark and in the charged lepton sectors, flavor diagonal but nonuniversal Higgs couplings set this model apart from the NFC versions of the 3HDM.

    hep-phPRD(2025)·5 citations
20. 20*

    Long-range interactions in double heavy tetraquarks $\bar{Q}\bar{Q}qq$

    Muhammad Naeem Anwar🇬🇧

    At the large distances compared to the chiral symmetry breaking scale, a four-quark system $\bar{Q}\bar{Q}qq$ (with $Q$ as heavy and $q$ as light quarks) can be treated as two asymptotic mesons interacting via strong residual forces. The static heavy quark assumption enables using the Born-Oppenheimer approximation, where one can compute the potential between two heavy antiquarks in the presence of two light quarks of finite mass -- a prescription utilized in several lattice QCD studies. To analyse the long-range strong force in a $\bar{Q}\bar{Q}qq$ system, we study the interaction between two bottom mesons in the heavy quark limit using chiral effective field theory and dispersion theory with unphysical pion mass. We present methods to obtain two-pion-exchange potential between two static heavy mesons at non-physical pion mass and compare our preliminary results with the corresponding lattice QCD potentials.

    hep-phhep-latnucl-thPoS(2025)·0 citations
21. 21*

    Next to Soft Threshold Resummation for $VH$ Production

    Arunima Bhattacharya🇪🇸 · Chinmoy Dey🇮🇳 · M. C. Kumar🇮🇳 · Vaibhav Pandey🇮🇳

    We study the threshold effects for the associated production of a Higgs boson with a massive vector boson $(V=Z,W)$ in the $q\bar{q}\to V^{\star }\to VH$ process at the LHC. By leveraging the universality of threshold logarithms and employing soft-virtual (SV) and next-to-soft virtual (NSV) resummation techniques, we compute threshold corrections to next-to-next-to-leading logarithmic accuracy. After matching the resummed predictions to the Next-to-Next-to-Leading order (NNLO) fixed order results, we present the invariant mass distribution to NNLO$+\overline{\text{NNLL}}$ accuracy in QCD for the current LHC energies and the total production cross sections. The $VH$ production channel is crucial for studying the couplings of the Higgs boson to the vector bosons $(W,Z)$ and understanding the mechanism of electroweak symmetry breaking. Precision measurements of this process help test the validity of the standard model (SM) and can reveal potential deviations indicating new physics.

    hep-phhep-exEur.Phys.J.ST(2025)·8 citations
22. 22*

    Rotational Brownian motion and heavy quark polarization in QCD medium

    Sourav Dey🇮🇳 · Amaresh Jaiswal🇮🇳

    We consider the rotational Brownian motion of heavy quark in QCD medium and provide analytical results for polarization of open heavy-flavor hadrons. We calculate expressions for vector and tensor polarization, corresponding to baryon spin polarization and vector meson spin alignment, respectively. Assuming that heavy quarks are initially fully spin polarized along the direction of magnetic field, we compare our results with recent experimental data from ALICE collaboration for $D^{\ast +}$ meson and provide predictions for spin polarization of open charm baryons. We propose that the transverse momentum dependence of heavy quark polarization may serve as a distinctive signature of the intense initial magnetic field generated in off-central relativistic heavy-ion collisions.

    hep-phnucl-thPLB(2026)·10 citations
23. 23*

    Phenomenology of the Higgs sector from Reduction of Couplings in the Type-II 2HDM

    Wojciech Kotlarski🇵🇱 · Gregory Patellis🇵🇹

    The idea of reduction of couplings provides a systematic procedure to search for relations among seemingly unrelated parameters of a renormalizable theory. As a consequence, such reduced theories exhibit more constrained parameter spaces. Motivated by this, in this work we perform a precise phenomenological analysis of the Higgs sector of a version of the Type-II 2HDM on which the idea of reduction of couplings has been applied. We compute Higgs boson masses and decay widths and confront them with current experimental measurements. Compared to the previous study, apart from the inclusion of actual experimental constraints on production and decay rates of Higgs bosons, we also include all model parameters in the RGE running as well as one- and two-loop threshold corrections and two-loop RGE running from the high scale. Furthermore, Higgs boson masses are now computed at the one-loop level. Top quark mass, which is an important prediction of the reduction framework, is now evaluated including previously missing sub-leading one-loop contributions, with an addition of up to four-loop pure-QCD corrections.

    hep-phEPJC(2026)·1 citation
24. 24*

    Colorful Particle Production at High-Energy Muon Colliders

    Tao Han🇺🇸 · Matthew Low🇺🇸 · Tong Arthur Wu🇺🇸 · Keping Xie🇺🇸

    A high-energy ${\mu }^{+}{\mu }^{-}$ collider provides a wide variety of mechanisms for the production of new heavy particles. While the reach for such particles via the direct annihilation of ${\mu }^{+}{\mu }^{-}$ will approach the center-of-mass energy of the collider, the partonic fusions from gauge bosons, quarks, and gluons, originating from the incoming muon beams will open new channels for single production and pair production of particles with different quantum numbers. We present the production rates for a wide variety of colored states including color-triplets, color-sextets, color-octets, leptoquarks, and leptogluons. We find that pair production from the direct annihilation of ${\mu }^{+}{\mu }^{-}$ generally has a cross section of $0.1-1$ fb once above the production threshold. On the other hand, pair production through the quark and gluon content of the muon leads to a cross section of roughly $10^{-4}$ fb at the same particle mass. We perform simple estimations of the mass reach for each particle and find that a 10 TeV muon collider can extend the reach for color-triplets beyond what is possible at the high luminosity run of the Large Hadron Collider. Leptoquarks and leptogluons, with sensitivity driven by single production, can also be probed to higher masses at a muon collider than what the Large Hadron Collider can reach. A final example where a muon collider has superior reach is for color-octet scalars and vectors. Together, these cases illustrate the point that a muon collider is a competitive machine for searching for colored heavy particles, thus strengthening the motivation for such lepton colliders in the energy frontier. Although our study is focused on a muon collider, our results are largely applicable to high-energy $e^{+}{e}^{-}$ collisions as well.

    hep-phhep-exJHEP(2025)·12 citations
25. 25*

    Cosmological Stasis from Field-Dependent Decay

    Fei Huang🇮🇱 · V. Knapp-Perez🇺🇸

    Cosmological stasis is a new type of epoch in the cosmological timeline during which the cosmological abundances of different energy components -- such as vacuum energy, matter, and radiation -- remain constant despite the expansion of the universe. Previous studies have shown that stasis naturally arises in various scenarios beyond the Standard Model, either through sequential decays of states in large towers or via the annihilation of a single particle species in thermal equilibrium with itself. In this work, we demonstrate that stasis can also emerge from the decay of a single particle species whose decay width is dynamically regulated by a scalar field rolling down a Hubble-mass potential. By analyzing the fixed points of the dynamical system, we identify regions of the parameter space where stasis occurs as a global attractor of cosmic evolution. We also find that, depending on the specific abundance configuration, stasis solutions can manifest as either a stable node with asymptotic behavior or a stable spiral exhibiting intrinsic oscillations. Furthermore, we present an explicit model for this realization of stasis and explore its phenomenological constraints and implications.

    hep-phastro-ph.COJHEP(2025)·7 citations
26. 26*

    Connecting Scales: RGE Effects in the SMEFT at the LHC and Future Colliders

    Jaco ter Hoeve🇬🇧 · Luca Mantani🇪🇸 · Alejo N. Rossia🇮🇹 · Juan Rojo🇳🇱 · Eleni Vryonidou🇬🇧

    Global interpretations of particle physics data within the framework of the Standard Model Effective Field Theory (SMEFT), including their matching to UV-complete models, involve energy scales potentially spanning several orders of magnitude. Relating these measurements among them in terms of a common energy scale is enabled by the Renormalisation Group Equations (RGEs). Here we present a systematic assessment of the impact of RGEs, accounting for QCD, electroweak, and Yukawa corrections, in a global SMEFT fit of LEP and LHC data where individual cross-sections are assigned a characteristic energy scale. We also quantify the impact of the RGE effects in projected global fits at the HL-LHC and the FCC-ee. Finally, we assess the role that RGEs play on the sensitivity at HL-LHC and FCC-ee to representative one-particle UV models matched onto SMEFT either at tree and one-loop level. Our study emphasizes the importance of a consistent treatment of energy scales to achieve the best precision and accuracy in indirect searches for heavy new physics through precision measurements.

    hep-phJHEP(2025)·46 citations
27. 27*

    Neutrino Emission and Plasma Heating from Primordial Black Holes: An Improved Approach to $N_{\mathrm{eff}}$ Constraints

    Héctor Sanchis🇪🇸 · Gabriela Barenboim🇪🇸 · Yuber F. Perez-Gonzalez🇪🇸

    We investigate the impact of neutrino emission via Hawking radiation from primordial black holes (PBHs) on the cosmological effective number of neutrino species, $N_{\mathrm{eff}}$, after neutrino decoupling. By comparing this effect with observational limits, we derive bounds on the abundance of light PBHs. Our analysis incorporates two previously unaccounted-for effects: the emission of secondary neutrinos from unstable particles, which increases $N_{\mathrm{eff}}$, and the modification of the neutrino-photon temperature ratio due to particle emission heating the photon plasma, which lowers $N_{\mathrm{eff}}$. Overall, including these effects allows us to impose constraints on PBHs with initial masses in the range $10^9\mathrm{g}\lesssim M_{\mathrm{ini}}\lesssim 10^{13}\mathrm{g}$. However, our limits remain less stringent than those derived from Big Bang Nucleosynthesis.

    ↳ astro-ph.COhep-phJCAP(2025)·6 citations
28. 28*

    Structure of center-vortex matter in SU(4) Yang-Mills theory

    Jackson A. Mickley🇦🇺 · Derek B. Leinweber🇦🇺 · Luis E. Oxman🇧🇷

    The structure of center vortices is studied in SU(4) Yang-Mills theory for the first time to illuminate the interplay between elementary (center charge $\pm 1$) and doubly charged vortices. Unlike in SU(3), where charge $+2$ vortices are simply elementary vortices with reversed orientations in spacetime, these possibilities are physically distinct in SU(4). Visualizations of the vortex structure in three-dimensional slices reveal the various ways in which doubly charged objects manifest, as the convergence and matching of elementary vortices or as isolated doubly charged loops. An algorithm is described to classify every doubly charged chain as one of these three types. A collection of vortex statistics is considered to quantify the vortex structure. Many of these pertain to the novel doubly charged objects, including their relative proportions and chain lengths, which are analyzed to highlight the differences between each chain type. Three different lattice spacings are employed to investigate the approach to the continuum limit. Vortex matching chains are found to be shorter on average but also more prevalent than vortex convergences, ascribed to their interpretation as extended center monopoles. In addition, the lengths of both vortex convergences and vortex matchings are observed to follow an exponential distribution, allowing the introduction of a constant probability for a doubly charged chain to split into two elementary vortices as it propagates. Combined, these findings provide a characterization of the vortices that comprise center-vortex structures in SU(4) Yang-Mills theory.

    ↳ hep-lathep-phhep-thnucl-thPRD(2025)·3 citations
29. 29*

    Gross-Llewellyn Smith sum rule from lattice QCD

    K. Utku Can🇦🇺 · Joshua A. Crawford🇦🇺 · Roger Horsley🇬🇧 · Paul E. L. Rakow🇬🇧 · Thomas G. Schar🇦🇺 · Gerrit Schierholz🇩🇪 · Hinnerk Stüben🇩🇪 · Ross D. Young🇦🇺 · James M. Zanotti🇦🇺

    We compute the Gross-Llewellyn Smith sum rule, i.e. the lowest odd moment of the parity-violating structure function, $F_3$, of the nucleon from a lattice QCD calculation of the Compton amplitude. Our calculations are performed on $48^3\times 96$ lattices at the $SU(3)$ symmetric point for two lattice spacings. We extract the moments for several values of the current momenta in the range $0.5\lesssim Q^2\lesssim 10{\mathrm{GeV}}^2$, covering both the nonperturbative and perturbative regimes. We compare our moments to the Gross-Llewellyn Smith sum rule and discuss the implications for higher-twist effects, a determination of ${\alpha }_s(Q^2)$ from a hadronic quantity complementing the phenomenological and other lattice approaches, and electroweak box contributions crucial for Cabibbo-Kobayashi-Maskawa matrix unitarity studies.

    ↳ hep-lathep-phnucl-exnucl-thPRD(2025)·3 citations
30. 30*

    Progress on lattice study of the chimera baryon spectrum in Sp(4) gauge theory

    C.-J. David Lin🇹🇼 · Ed Bennett🇬🇧 · Niccolò Forzano🇬🇧 · Deog Ki Hong🇰🇷 · Ho Hsiao🇹🇼 · Jong-Wan Lee🇰🇷 · Biagio Lucini🇬🇧 · Maurizio Piai🇬🇧 · Davide Vadacchino🇬🇧 · Fabian Zierler🇬🇧

    Investigation of composite Higgs models (CHMs) is of importance in contemporary particle physics. In this article, we present lattice computations of the chimera baryon masses in $Sp(4)$ gauge theory with two and three Dirac flavours of hyperquarks (beyond the Standard Model fermions coupled to the $Sp(4)$ gauge fields) in the fundamental and antisymmetric representations, respectively. The chimera baryons are crucial for generating the Standard Model fermion masses through the partial compositeness mechanism in this gauge theory that can serve as the ultraviolet completion of the CHM with pseudo-Nambu-Goldstone bosons in the coset $SU(4)/Sp(4)$. Results shown here are primarily from a completed quenched computation, while those from our ongoing work with dynamical simulations are also discussed.

    ↳ hep-lathep-phPoS(2025)·1 citation
31. 31*

    Color-magnetic correlations in SU(N) lattice QCD

    Hideo Suganuma (Kyoto U.)🇯🇵 · Atsuya Tokutake (Kyoto U.)🇯🇵 · Kei Tohme (Kyoto U.)🇯🇵

    Motivated by color-magnetic instabilities in QCD, we investigate field-strength correlations in both SU(2) and SU(3) lattice QCD. In the Euclidean Landau gauge, we numerically calculate the perpendicular-type color-magnetic correlation, $C_{\perp }(r)\equiv g^2⟨H_z^a(s)H_z^a(s+r\hat{\perp }))⟩$ with $\perp \equiv x,y$, and the parallel-type one, $C_{\parallel }(r)\equiv g^2⟨H_z^a(s)H_z^a(s+r\hat{\parallel })⟩$ with $\parallel \equiv z,t$. In the Landau gauge, all two-point field-strength correlations $g^2⟨G_{\mu \nu }^a(s)G_{\alpha \beta }^b(s^{\prime })⟩$ are described by these two quantities, due to the Lorentz and global SU($N_c$) color symmetries. Curiously, the perpendicular-type color-magnetic correlation $C_{\perp }(r)$ is found to be always negative for arbitrary $r$, except for the same point of $r=0$. The parallel-type color-magnetic correlation $C_{\parallel }(r)$ is always positive. In the infrared region, $C_{\perp }(r)$ and $C_{\parallel }(r)$ strongly cancel each other, which leads to an approximate cancellation for the sum of the field-strength correlations as ${\sum }_{\mu ,\nu }⟨G_{\mu \nu }^a(s)G_{\mu \nu }^a(s^{\prime })⟩\propto C_{\perp }(|s-s^{\prime }|)+C_{\parallel }(|s-s^{\prime }|)\simeq 0$. Next, we decompose the perpendicular-type color-magnetic correlation $C_{\perp }(r)$ into quadratic, cubic and quartic terms of the gluon field $A_{\mu }$. The quadratic term is always negative, which is explained by the Yukawa-type gluon propagator $⟨A_{\mu }^a(s)A_{\mu }^a(s^{\prime })⟩\propto e^{-mr}/r$ with $r\equiv |s-s^{\prime }|$ in the Landau gauge. The quartic term gives a relatively small contribution. In the infrared region, the cubic term is positive and tends to cancel with the quadratic term, resulting in a small value of $C_{\perp }(r)$.

    ↳ hep-lathep-phhep-thPoS(2025)·1 citation
32. 32*

    Constraints on New Physics with Light Mediators and Generalized Neutrino Interactions via Coherent Elastic Neutrino Nucleus Scattering

    S. Karadağ · M. Deniz · S. Karmakar · M. K. Singh · M. Demirci · Greeshma C. · H. B. Li · S. T. Lin · M. F. Mustamin · V. Sharma · L. Singh · M. K. Singh · V. Singh · H. T. Wong

    We investigate new physics effects on coherent elastic neutrino nucleus scattering within the framework of nonstandard interactions and generalized neutrino interactions. Additionally, we examine the possibility of light mediators from a simplified model that includes all possible Lorentz-invariant interactions of vector, axialvector, scalar, pseudoscalar, and tensor types. Constraints and allowed regions at the $90\%$ CL for masses and couplings in each new physics scenario have been obtained through the analysis of TEXONO data, which includes two datasets from a high-purity $n$-type point contact germanium detector in 2016 and an advanced $p$-type point contact Ge detector in 2025. The results are presented in comparison with other reactor and accelerator-based neutrino experiments for complementarity.

    ↳ hep-exhep-phPRD(2025)·13 citations
33. 33*

    The ${\eta }^{\prime }N$ interaction from the ${\eta }^{\prime }p$ correlation function

    Natsumi Ikeno🇯🇵

    We evaluate for the first time the ${\eta }^{\prime }p$ femtoscopic correlation function to study the ${\eta }^{\prime }N$ interaction. We find it extremely sensitive to the value of the ${\eta }^{\prime }p$ scattering length, for which at present there exists only very limited information, not even knowing its sign. The measurement of this correlation function would provide much valuable information on the ${\eta }^{\prime }N$ interaction, which could then also be used to settle the issue of possible ${\eta }^{\prime }$ nucleus bound states, an issue attracting much attention in the nuclear physics community.

    ↳ nucl-thhep-exhep-phnucl-exEPJA(2025)·7 citations
34. 34*

    Inferring the Equation of State from Neutron Star Observables via Machine Learning

    N. K. Patra🇨🇳 · Tuhin Malik🇵🇹 · Helena Pais🇵🇹 · Kai Zhou🇨🇳 · B. K. Agrawal🇮🇳 · Constança Providência🇵🇹

    We have conducted an extensive study using a diverse set of equations of state (EoSs) to uncover strong relationships between neutron star (NS) observables and the underlying EoS parameters using symbolic regression method. These EoS models, derived from a mix of agnostic and physics-based approaches, considered neutron stars composed of nucleons, hyperons, and other exotic degrees of freedom in beta equilibrium. The maximum mass of a NS is found to be strongly correlated with the pressure and baryon density at an energy density of approximately 800 MeV.fm${}^{-3}$. We have also demonstrated that the EoS can be expressed as a function of radius and tidal deformability within the NS mass range 1-2$M_{\odot }$. These insights offer a promising and efficient framework to decode the dense matter EoS directly from the accurate knowledge of NS observables.

    ↳ nucl-thastro-ph.HEastro-ph.SRgr-qc+1PLB(2025)·19 citations
35. 35*

    General Constraints on Isocurvature from the CMB and Ly-$\alpha$ Forest

    Matthew R. Buckley🇺🇸 · Peizhi Du🇨🇳 · Nicolas Fernandez🇺🇸 · Mitchell J. Weikert🇺🇸

    Current cosmological data are well-described by the Lambda-Cold Dark Matter ($\Lambda$CDM) model, which assumes adiabatic initial conditions for the primordial density perturbations. This agreement between data and theory enables strong constraints on new physics that generates isocurvature perturbations. Existing constraints typically assume a simple power law form for the isocurvature power spectrum. However, many new physics scenarios -- such as cosmological phase transitions and gravitational particle production -- can deviate from this assumption. To derive general constraints which apply to a wide variety of new physics scenarios, we consider four types of isocurvature modes (dark matter, baryon, dark radiation and neutrino density isocurvature) and parametrize the isocurvature power spectrum using two general forms: a delta function and a broken power law. Using data from the cosmic microwave background (CMB), baryon acoustic oscillations, the Lyman-$\alpha$ forest, and CMB spectral distortions, we place constraints on the isocurvature power spectrum across a wide range of scales, from $10^{-4}{\text{Mpc}}^{-1}$ to $10^4{\text{Mpc}}^{-1}$.

    ↳ astro-ph.COhep-phJCAP(2025)·33 citations
36. 36*

    Dynamical dark energy in 0'B braneworlds

    Ivano Basile🇩🇪 · Alessandro Borys🇩🇪 · Joaquin Masias🇩🇪

    We build a novel realization of dark bubble cosmology in non-supersymmetric string theory. Among the simplest models in ten dimensions, the type 0'B orientifold is the unique option which yields a scale-separated construction. The resulting setting produces a logarithmically varying dynamical dark energy, reflecting its holographic counterpart in terms of running gauge couplings. We analyze in detail the phenomenological consequences of the model for particle physics, inflation and late-time cosmology. We find that, although particle physics may be consistently realized, neither early-time nor late-time are observationally viable.

    ↳ hep-thgr-qchep-phEPJC(2025)·9 citations
37. 37*

    Thermal Field Theory in the Presence of a Background Magnetic Field and its Application to QCD

    Munshi G. Mustafa🇮🇳 · Aritra Bandyopadhyay🇷🇴 · Chowdhury Aminul Islam🇩🇪

    This review has explored the fundamental principles of thermal field theory in the context of a background magnetic field, highlighting its theoretical framework and some of its applications to the thermo-magnetic QCD plasma generated in heavy-ion collisions. Our discussion has been limited to equilibrium systems for clarity and conciseness. We analysed bulk thermodynamic characteristics, including the phase diagram as well as real-time observables, shedding light on the behaviour and dynamics of the thermo-magnetic QCD medium relevant to heavy-ion physics.

    ↳ nucl-thhep-lathep-phPPNP(2026)·5 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.