Fri·Jun 13, 2025Friday·June 13, 2025

1. 01*

   RG evolution and effect of intermediate new physics on $\Delta B=2$ six-quark operators

   Mathew Thomas Arun🇮🇳 · Shyam M🇮🇳 · Ritik Pal🇮🇳

   The recent identification of possible 11 neutron-antineutron ($n$-$\bar{n}$) oscillation candidate events at Super-Kamiokande has renewed the interest in $\Delta B=2$ transitions. In this work, we analyze the Renormalization Group (RG) running of mass dimension-9 six-quark operators, in $\overline{MS}$ scheme, that generate processes like $nn\to {\pi }^0{\pi }^0$, deuteron decay, $n$-$\bar{n}$ oscillations etc, evolving them from the electroweak scale to baryon number violating scale ($\mathcal{O}(10^3\text{TeV})$). Our goal is to systematically account for the influence of potential new physics at intermediate energies ($\gtrsim \mathcal{O}(10\text{TeV})$), especially given the fact that {\it Large Hadron Collider} has not ruled out new physics beyond $\sim 10\text{TeV}$. To comprehensively investigate their influence, we consider two scenarios: (i) a minimal setup with only Standard Model degrees of freedom up to the high scale at $\mathcal{O}(10^3\text{TeV})$, and (ii) an extended framework involving scalar and vector bosons above $\sim 10\text{TeV}$ up till BNV scale. To facilitate further studies, we also provide a Python script that performs RG evolution of the BNV Wilson coefficients in the presence of generic bosonic new physics at any intermediate energy scale. It can be modified easily to meet the needs of the user to investigate the running of the BNV Wilson coefficients. We then compare the result with the experimental bound from the neutron-antineutron oscillation process and constrain the scale of baryon number violating new physics.

   hep-phJHEP(2025)·6 citations
2. 02*

   Matter symmetries in supersymmetric standard models from non-invertible selection rules

   Tatsuo Kobayashi🇯🇵 · Hironobu Mita🇯🇵 · Hajime Otsuka🇯🇵 · Riku Sakuma🇯🇵

   We discuss phenomenological implications of non-invertible selection rules in the framework of the supersymmetric standard model. We find that a remnant ${\mathbb{Z}}_2$ symmetry of fusion algebras which holds at all-loop order plays the role of $R$-parity, forbidding baryon and lepton violating operators. In addition, a combination of Standard Model gauge symmetry and the non-invertible selection rules lead to baryon triality and proton hexality that can protect the proton from decay. In general, our finding selection rules can not realize the same results as conventional ${\mathbb{Z}}_N$ symmetries in the supersymmetric standard model. We also clarify the assignments of matter fields under the fusion algebras that are consistent with $SU(4)\times SU(2)\times SU(2)$, $SU(5)$, and $SO(10)$ grand unified theories.

   hep-phhep-thPTEP(2026)·26 citations
3. 03*

   New evidence for the rapidity evolution in Mueller-Navelet dijet production: BFKL, Sudakov, and RG-invariance

   A.A. Chernyshev🇷🇺 · M.A. Nefedov🇮🇱 · V.A. Saleev🇷🇺

   We study the effects of matching of the high-energy resummation based on the BFKL equation with initial state radiation effects, taken into account within the framework of high-energy factorization, in the production of Mueller-Navelet dijets. We use RG-invariant solution of the NLO BFKL equation built out of eigenfunctions perturbatively constructed up to NLO to avoid the need for a special renormalization scale setting. We demonstrate that various data sets from the FNAL Tevatron and CERN LHC can be described in this way and both, the NLL BFKL resummation and initial state radiation effects of the high-energy factorization, are crucial for the uniform description of the data across all values of the rapidity difference between the jets. The behavior of angular distributions and ratios of angular coefficients with increasing rapidity separation between the jets provides clear evidence for the BFKL dynamics at the FNAL Tevatron and CERN LHC.

   hep-ph5 citations
4. 04*

   Systematic study of light and charm meson M1 radiative transitions

   Binesh Mohan🇮🇳 · Christas Mony A.🇮🇳 · Rohit Dhir🇮🇳

   Motivated by recent experimental advancements in the study of radiative decays of charmed mesons, we investigate the magnetic (transition) moments of vector mesons by applying the effective mass scheme, obtained from the one-gluon exchange interaction between quark-antiquark pairs. By incorporating high-precision experimental data from both heavy and light flavor sectors, we accurately account for the strong hyperfine interaction contributions to the quark and antiquark masses within mesons. We calculate the $V\to P$ effective transition magnetic moments to reliably predict M1 decay widths. Furthermore, to enhance the completeness of our analysis, we employ the non-relativistic potential model to calculate bound state isomultiplet masses and to predict the M1 decay widths of charmed mesons. Additionally, scale-dependent effects in both the effective mass scheme and the potential model are systematically analyzed and interpreted, emphasizing the decisive role of higher-order QCD corrections in determining M1 decay widths.

   hep-phhep-exEur.Phys.J.Plus(2026)·4 citations
5. 05*

   Evading Dark Matter Bounds through NLSP-Assisted Freeze-Out with Long-Lived Signatures

   Sarif Khan🇰🇷

   In this work, we explore a conversion-driven freeze-out scenario, where the next-to-lightest stable particle (NLSP) sets the dark matter (DM) abundance through the process ``NLSP SM $\leftrightarrow$ DM SM". Although DM is produced via a freeze-out mechanism, its interaction strength with the visible sector can range from weak to feeble couplings. This results in a vast, largely unexplored parameter space that evades current direct, indirect, and collider bounds, while remaining testable in the near future. We study this mechanism in the context of an alternative $U(1{)}_{B-L}$ model, where four chiral fermions are required to cancel gauge anomalies, unlike the usual case with three right-handed neutrinos. The observed relic abundance is successfully reproduced within this framework. The viable parameter space can be probed by future direct detection experiments, while remaining inaccessible to indirect searches. Our results show that the DM relic density is highly sensitive to the NLSP-SM interaction strength and the mass difference between the NLSP and DM, but not to the DM-SM direct interaction. For certain parameter choices, the NLSP decays to DM via two or three body processes involving an extra gauge boson and SM particles, leading to long-lived decays outside the CMS or ATLAS detectors at the LHC. In contrast, if the decay proceeds via a CP-odd Higgs, it occurs promptly within the detector. We investigate prospects for detecting such long-lived NLSPs at the proposed MATHUSLA detector, with similar expectations for the ongoing FASER experiment. Finally, we find that choosing arbitrarily small values of the gauge coupling or BSM fermionic mixing angle can violate successful BBN predictions.

   hep-phJHEP(2026)·2 citations
6. 06*

   Revisiting Roy-Steiner-equation analysis of pion-kaon scattering from lattice QCD data

   Xiong-Hui Cao🇨🇳 · Feng-Kun Guo🇨🇳 · Zhi-Hui Guo🇨🇳 · Qu-Zhi Li🇨🇳

   A comprehensive analysis of $\pi K\to \pi K$ and $\pi \pi \to K\bar{K}$ amplitudes at large unphysical pion mass for all important partial waves is presented. A set of crossing-symmetric partial-wave hyperbolic dispersion relations is used to describe lattice QCD data at $m_{\pi }=391$ MeV. In the present analysis, the amplitudes for the $S$- and $P$-waves are formulated by combining the constraints of analyticity, unitarity, and crossing symmetry, fulfilling Roy-Steiner-type equations. We use these results to investigate the low-lying strange-meson resonances and resolve the instability problem tied to analytic continuation in prior lattice QCD studies based on the $K$-matrix formalism. At $m_{\pi }=391$ MeV, the rigorous Roy-Steiner-type equation approach allows us to determine the $S$-wave scattering lengths, $m_{\pi }{a}_0^{1/2}=\left(0.92_{-0.28}^{+0.06}\right)$, $m_{\pi }{a}_0^{3/2}=-\left(0.32_{-0.02}^{+0.05}\right)$, and the $\kappa$ (also known as $K_0^{\ast }(700)$) pole position, $\sqrt{s_{\kappa }}=\left(966_{-24}^{+41}-i198_{-17}^{+38}\right)$ MeV. We also provide a detailed analysis of the complex validity domain of the Roy-Steiner-type equations.

   hep-phPRD(2025)·9 citations
7. 07*

   Personal Memories of 50 Years of Quarkonia

   John Ellis🇬🇧

   The world of particle physics was revolutionised in November 1974 by the discovery of the J/psi particle, the first particle to be identified as a quarkonium state composed of charm quarks and antiquarks. The charmonium interpretation of the J/psi was cemented by the subsequent observations of a spectrum of related c \bar c states, and finally by the discovery of charmed particles in 1976. The discovery of charmonium was followed in 1977 by the discovery of bottomonium mesons and particles containing bottom quarks. Toponium bound states of top quark and antiquarks were predicted to exist in principle but, following the discovery of the top quark in 1995, most physicists thought that its observation would have to wait for next-generation e^+ e^- collider. However, in the second half of 2024 the CMS Collaboration reported an excess of events near the threshold for \bar t t production at the LHC that is most plausibly interpreted as the lowest-lying toponium state. These are the personal recollections of an eyewitness who followed closely these 50 years of quarkonium discoveries.

   hep-phhep-exphysics.hist-phNPB(2025)·8 citations
8. 08*

   Regge factorization of tree-level QCD amplitudes using a minimal set of lightcone variables

   Emmet P. Byrne🇬🇧 · Vittorio Del Duca🇮🇹 · Einan Gardi🇬🇧 · Yuyu Mo🇬🇧 · Jennifer M. Smillie🇬🇧

   We represent the multi-leg tree-level amplitudes of quarks and gluons using a minimal set of lightcone variables, which incorporate all on-shell and momentum conservation conditions and naturally captures the separate longitudinal and transverse momentum components. These variables make it easy to eliminate spurious poles and consider multi-Regge kinematic limits. In this framework we examine the factorization of tree-level amplitudes in rapidity and extract all two, three and four parton Multi-Regge Emission Vertices (MREVs), both central and peripheral, and summarise them in a Mathematica library, MREV. We investigate in detail how relations between amplitudes translate into relations between MREVs. These relations, along with factorization properties in further kinematic limits, provide robust consistency checks of the results.

   hep-phhep-thJHEP(2026)·5 citations
9. 09*

   Baryon and Meson Excited States

   L. David Roper (VTech)🇺🇸 · Igor Strakovsky (GWU)🇺🇸

   The masses of fifteen baryon sets and twenty-four meson sets of three or more equal-quantum excited states are fitted by a simple two-parameter logarithm function, $M_n=\alpha Ln(n)+\beta$, where $n$ is the level of radial excitation. The conjecture is made that accurately measured masses using Breat-Wigner PDG2024 data at fixed $J^P$ for baryons and $J^{PC}$ for mesons of all equal-quantum baryons (including LHCb exotic $P_{c\bar{c}}^{+}$s) and meson (including $s\bar{s}$, $s\bar{c}$, $c\bar{c}$, $c\bar{b}$, and $b\bar{b}$) excited states are related by the logarithm function used here; at least for the mass range of currently known excited states. Thus, a universal mass equation for equal-quantum excited-states sets is presented. The masses of twelve baryon sets and sixteen meson sets, with only two equal-quantum excited states in each set, using Breit-Wigner PDG2024 masses and their uncertainties, are fitted by thr universal mass equation.

   hep-phhep-exnucl-exnucl-thPoS(2026)·0 citations
10. 10*

    Entanglement entropy for ${\pi }^{+}p$ elastic scattering using spin-density matrix

    Seung-il Nam🇰🇷

    We study the ${\pi }^{+}p$ elastic scattering process using an effective Lagrangian approach that incorporates the $s$-, $u$-, and $t$-channel amplitudes, including ${\Delta }^{++}(1232)$, ${\Delta }^0(1232)$, neutron, and ${\rho }^0$ contributions. By constructing the spin-density matrices from the scattering amplitudes, we derive the von Neumann (entanglement) entropy associated with the spin degrees of freedom of the initial and final state particles. We compute the entropy by performing a partial trace over the spin subsystems, and its behavior is analyzed as a function of the center-of-mass energy $W$ and scattering angle $\theta$. We find that entropy exhibits nontrivial angular and energy dependences, reflecting the interplay among resonance contributions and background amplitudes. In particular, the ${\Delta }^{++}$ region shows relatively low entanglement, suggesting spin coherence dominated by the specific resonant contribution, while the background contributions increase entropy due to mixed spin configurations. These results indicate that entanglement entropy can serve as a novel probe into the quantum structure of hadronic scattering amplitudes, providing complementary insights beyond conventional cross-section analyses.

    hep-phPRC(2026)·2 citations
11. 11*

    Ultimate Quantum Precision Limit at Colliders: Conditions and Case Studies

    Tengyu Ai🇨🇳 · Qi Bi🇨🇳 · Yuxin He🇨🇳 · Jia Liu🇨🇳 · Xiao-Ping Wang🇨🇳

    We investigate whether collider experiments can reach the quantum limit of precision, defined by the quantum Fisher information (QFI), using only classical observables such as particle momenta. As a case study, we focus on the ${\tau }^{+}{\tau }^{-}$ system and the decay channel $\tau \to \pi \nu$, which offers maximal spin-analyzing power and renders the decay a projective measurement. We develop a general framework to determine when collider measurements can, in principle, saturate the QFI in an entangled biparticle system, and this framework extends naturally to other such systems. Within this framework, QFI saturation occurs if and only if the symmetric logarithmic derivative (SLD) commutes with a complete set of orthonormal separable projectors associated with collider-accessible measurements. This separability condition, reflecting the independence of decay amplitudes, is highly nontrivial. To meet this condition, a key requirement is that the spin density matrix be rank-deficient, allowing the SLD sufficient freedom. We show that the classical Fisher information asymptotically saturates the QFI for magnetic dipole moments and CP-violating Higgs interactions in selected phase-space regions, but not for electric dipole moments. These results bridge quantum metrology and collider physics, providing a systematic method to identify quantum-optimal sensitivity in collider experiments.

    hep-phhep-exquant-phPRL(2025)·13 citations
12. 12*

    Unraveling the neutron skin thickness through jet charge in deep inelastic scattering

    Shan-Liang Zhang🇨🇳 · Enke Wang🇨🇳 · Xin-Nian Wang🇨🇳 · Hongxi Xing🇨🇳

    The neutron skin thickness in neutron-rich nuclei has traditionally been measured using elastic fixed target electron-nucleus scattering since the 1970s. In this paper, we propose a novel probe of the neutron skin thickness through deep inelastic scattering in electron-ion collisions, leveraging the intrinsic correlation between final-state jet charge distribution and initial-state partonic distributions in nucleons. Specifically, we demonstrate the sensitivity of jet charge distribution to the neutron skin thickness in $e$+Pb collisions with varying centralities, and in isobar collisions of $e$+Ru and $e$+Zr. We predict a strong suppression of positive jet charge distribution and an enhancement for negative jet charge distribution in peripheral electron-ion collisions, revealing the neutron skin effect. This proposal can also be extended to photon and Z-boson tagged jet charge distribution in proton-nucleus collisions at the Large Hadron Collider, providing an alternative access to neutron skin thickness.

    hep-phhep-exnucl-exnucl-th4 citations
13. 13*

    Extraction of Effective Parameters from Transverse Momentum Spectra of Heavy Quarkonia in Proton-Proton Collisions at the LHC

    Peng-Cheng Zhang🇨🇳 · Hailong Zhu🇨🇳 · Fu-Hu Liu🇨🇳 · Khusniddin K. Olimov🇺🇿

    The effective string tension ($\kappa$) in the Schwinger mechanism and the effective temperature ($T$) in Bose-Einstein statistics are extracted from the transverse momentum ($p_T$) spectra of heavy quarkonia produced in proton-proton (p+p) collisions at the Large Hadron Collider (LHC). Here, $T$ derived from the heavy quarkonium $p_T$ spectra also serves as the initial effective temperature (effective temperature at the initial stage) of small collision systems. This is because, despite the absence of quark-gluon plasma (QGP) formation during the collisions, which leaves $T$ largely unaffected by QGP-related effects, the initial geometric asymmetry and local partonic thermalization still induce radial and transverse flows, thereby contributing to an increase in $T$. The effective parameters ($\kappa$ and $T$) are obtained by fitting the experimental $p_T$ spectra of $J/\psi$ and ${\rm Y}(nS)$ ($n=1$, 2, and 3) within various rapidity intervals, produced in p+p collisions at center-of-mass energies of $\sqrt{s}=13$ and 8 TeV, as measured by the LHCb Collaboration. It is found that the multi-component distribution structured within the framework of the Schwinger mechanism or Bose-Einstein statistics can effectively describe the heavy quarkonium $p_T$ spectra in small collision systems. With decreasing rapidity in the forward region, both $\kappa$ and $T$ increase, indicating a directly proportional relationship between them. Based on $\kappa$, the average minimum strong force radius of participant quarks is determined.

    hep-phhep-exnucl-exnucl-thAdv.High Energy Phys.(2026)·0 citations
14. 14*

    Double neutral-current corrections to NLO electroweak leptonic cross sections

    Stefano Frixione🇮🇹 · Fabio Maltoni🇧🇪 · Davide Pagani🇮🇹 · Marco Zaro🇮🇹

    We present a method for improving next-to-leading order electroweak (EW) predictions for lepton-scattering processes by consistently including double neutral-current corrections arising from vector-boson-fusion topologies, which are formally of higher order. By combining, in a process-independent manner, exact fixed-order results, collinear resummation of QED radiation, and a subtraction procedure, we obtain results which are gauge invariant and valid in the entire phase space, retain any dependence on the masses of electroweak bosons, and can be systematically improved, while avoiding the need for complete next-to-next-to-leading order calculations. This paper is devoted to the development and validation of the formalism; phenomenological applications are presented in a companion study, where we also discuss and motivate why our approach is superior to the one based on EW parton distribution functions for targeting percent-level precision at multi-TeV lepton colliders.

    hep-phJHEP(2025)·7 citations
15. 15*

    Precision phenomenology at multi-TeV muon colliders

    Stefano Frixione🇮🇹 · Fabio Maltoni🇧🇪 · Davide Pagani🇮🇹 · Marco Zaro🇮🇹

    Future lepton colliders, such as those based on linear $e^{+}{e}^{-}$ or circular ${\mu }^{+}{\mu }^{-}$ accelerators, are expected to attain centre-of-mass energies in the multi-TeV range. In this regime the impact of QED and of weak radiation, in both the initial and the final state, can become a leading effect. By employing a general framework presented in a companion paper - suitable for any flavour of colliding leptons - we improve next-to-leading order electroweak predictions by including higher-order contributions, which encompass, but are not limited to, vector-boson-fusion processes. We apply this approach to the study of $t\bar{t}$ and $W^{+}{W}^{-}$ production at a muon collider operating at centre-of-mass energies up to 10 TeV. We show that such an approach, where both QED and weak contributions are included at fixed order, in addition to the all-order resummation of initial-state QED effects, can provide predictions for arbitrary observables in all of the phase space which are precise at the percent level.

    hep-phJHEP(2025)·11 citations
16. 16*

    Impact of improved energy resolution on DUNE sensitivity in presence of a light sterile neutrino

    Sabila Parveen🇮🇳 · Jogesh Rout🇮🇳 · Poonam Mehta🇮🇳

    The Deep Underground Neutrino Experiment (DUNE) primarily aims to measure the yet unknown parameters of the standard three neutrino framework, i.e., the determination of Dirac CP phase (${\delta }_{13}$), neutrino mass hierarchy (MH) and octant of ${\theta }_{23}$. In the present work, we consider the standard three neutrino paradigm (referred to as the $(3+0)$ case) and beyond with an additional light sterile neutrino (referred to as the $(3+1)$ case). We consider two configurations : standard energy resolution as in DUNE Technical Design Report (TDR) and improved energy resolution and study the impact of energy resolution in the $(3+0)$ and $(3+1)$ cases. In general, inclusion of subdominant new physics effects spoils the sensitivities. However, improved energy resolution leads to enhancement in sensitivities to the three unknowns in both $(3+0)$ and $(3+1)$ cases.

    hep-ph0 citations
17. 17*

    Electric conductivity and flavor diffusion in a viscous, resistive quark-gluon plasma for weak and strong magnetic fields

    Ferdinando Frascà🇮🇹 · Andrea Beraudo🇮🇹 · Luca Del Zanna🇮🇹

    We present a microscopic calculation of the electric conductivity and net-particle diffusion coefficients for a viscous and resistive ultra-relativistic plasma. Our results might be of interest for several astrophysical and cosmological problems, but the main physical application we have in mind is the hot deconfined matter produced in relativistic heavy-ion collisions. Accordingly, as charged particles of the medium we take three species (flavors) of light (massless for the sake of simplicity) quarks -- $u$, $d$ and $s$ -- and antiquarks, entailing the existence of three macroscopic conserved charges: baryon number $\mathcal{B}$, electric charge $Q$ and strangeness $S$. Our results are valid both in a weakly and in a strongly-magnetized plasma, where the energy stored in the magnetic field is comparable to the one carried by the medium particles. Actually, for a conformal fluid, the behavior of the system only depends on the ratio between the thermal and the magnetic pressure, the so-called plasma beta-parameter, acting as a scaling variable. Our calculation, starting from a relativistic Boltzmann-Vlasov equation, is based on a generalized Chapman-Enskog approach in which space-time gradients and the local electric field are treated as first-order quantities in a perturbative expansion, while terms containing magnetic corrections are considered of zeroth order and hence self-consistently resummed. We find that, also in the strong-field limit, for each conserved charge a generalized Wiedemann-Franz law, connecting charge conductivity and diffusion coefficient, exists. However these transport coefficients acquire a non-trivial tensor structure, reflecting the development of a longitudinal, a transverse and a Hall current as a response to electric fields or density gradients.

    hep-phastro-ph.HEnucl-thEPJC(2025)·1 citation
18. 18*

    Threshold resummation for $W$-boson pair production at NNLO+NNLL

    Pulak Banerjee🇮🇹 · Chinmoy Dey🇮🇳 · M. C. Kumar🇮🇳 · Vaibhav Pandey🇮🇳

    We present results for threshold resummation of the invariant mass distribution, for on-shell production of a pair of $W$-bosons at next-to-next-to-leading order + next-to-next-to-leading logarithmic (NNLO+NNLL) accuracy in QCD. Owing to its sensitivity to the self-interactions between gauge bosons, this process is important to investigate at the energies of the Large Hadron Collider (LHC). We achieve this resummation by exploiting the factorization properties of the soft and virtual parts of the partonic cross-section. Our analysis has been carried out for the invariant mass distribution up to $Q$ = 2500 GeV. At this highest $Q$ we find that, for 13.6 TeV LHC, the NNLL resummation enhances the NNLO cross-sections by about $6.3\%$ and reduces the conventional scale uncertainties from 6.8\% at NNLO to 4.1\% at NNLO+NNLL. We also estimate the intrinsic uncertainties due to the non-perturbative parton distribution functions at the highest perturbative order, for both fixed-order and resummed results, to be around 3\% for $Q\sim$ 2000 GeV.

    hep-phhep-exEPJC(2026)·2 citations
19. 19*

    Two coincidences are a clue: Probing a GeV-scale dark QCD sector

    Yi Chung🇩🇪

    The similarity between the dark matter and baryon energy densities suggests an existence of a dark sector analogous to QCD. In addition, small-scale structure anomalies can be addressed by dark matter self-interactions with cross sections comparable to those of QCD. Both observations point toward a GeV-scale dark QCD sector. Motivated by these two coincidences, we investigate the parameter space of a distinctive chiral dark QCD model featuring a MeV-scale dark photon with axial-vector couplings. We also discuss a possible third coincidence associated with the latest measurement of $N_{\mathrm{eff}}$. Current constraints leave a finite and testable region of parameter space that can be probed by future experiments such as the Gamma Factory.

    hep-phastro-ph.COastro-ph.GAEPJC(2026)·3 citations
20. 20*

    Multiple Soft Scatterings in Scalar Dark Matter Freeze-In

    Mathias Becker🇮🇹 · Maria Jose Fernandez Lozano🇩🇪 · Julia Harz🇩🇪 · Carlos Tamarit🇩🇪

    We present an improved calculation of the freeze-in production rate for scalar dark matter (DM) from a gauge-charged parent particle via a renormalizable interaction. Building on the previously developed 1PI-resummed framework to accurately capture the relevant regime $T\sim M$, we expand the analysis to include the Landau-Pomeranchuk-Migdal (LPM) effect, which contributes at leading order $g^{2}T$ to the interaction rate in the ultra-relativistic limit. To this end, we derive an equation for the LPM rate of a scalar particle for the first time and combine it with the previous 1PI results, providing a new state-of-the art calculation. In contrast to the 1PI results, the LPM treatment neglects vacuum mass scales such that a phenomenological switch-off function between the ultra-relativistic and non-relativistic regime is required. We propose a new function motivated by a thermal loop contribution and compare it to other approaches in the literature, quantifying the resulting uncertainty of this method. Depending on the gauge coupling and mass splitting between DM and mediator particles, the LPM effect contributes between 1% and 27% to the relic density, with the impact increasing for larger gauge couplings and smaller mass splittings. Additionally, we compare our results to commonly used semi-classical Boltzmann approaches. For instance, when these include decays and scatterings regulated with thermal masses, we find deviations ranging from -30% to +20% depending on the mass splitting. Finally, we compare to results based on hard-thermal-loop (HTL) approximations.

    hep-phJCAP(2026)·6 citations
21. 21*

    Spin-Dependent Scattering of Sub-GeV Dark Matter: Models and Constraints

    Stefania Gori🇺🇸 · Simon Knapen🇺🇸 · Tongyan Lin🇺🇸 · Pankaj Munbodh🇺🇸 · Bethany Suter🇺🇸

    We calculate the scattering rate of sub-GeV dark matter in solid-state targets for spin-dependent dark matter -- nucleon interactions. For dark matter particles with mass below 100 MeV, the scattering occurs predominantly through incoherent phonon production. For dark matter heavier than 100 MeV, we match onto the nuclear recoil calculation. To compare the sensitivity of future direct detection experiments with existing constraints, we consider three models with interactions which are mediated by spin-0 or spin-1 particles. This allows us to derive bounds on the cross section from searches for the mediating particle, including bounds from stellar cooling, beam dump experiments, meson factories and dark matter self-interactions. The existing bounds are very stringent, though for $m_{\chi }\gtrsim 100$ MeV there is parameter space which may be accessible with direct detection, depending on the exposure and background rates.

    hep-phPRD(2025)·14 citations
22. 22*

    Quirk SUEP

    David Curtin🇨🇦 · Sascha Dreyer🇩🇪 · Max Fusté Costa🇩🇪 · Sarah Heim🇩🇪 · Gregor Kasieczka🇩🇪 · Louis Moureaux🇩🇪 · David Rousso🇩🇪 · David Shih🇺🇸 · Manuel Sommerhalder🇩🇪

    We propose searching for physics beyond the Standard Model in the low-transverse-momentum tracks accompanying hard-scatter events at the LHC. TeV-scale resonances connected to a dark QCD sector could be enhanced by selecting events with anomalies in the track distributions. As a benchmark, a quirk model with microscopic string lengths is developed, including a setup for event simulation. For this model, strategies are presented to enhance the sensitivity compared to inclusive resonance searches: a simple cut-based selection, a supervised search, and a model-agnostic weakly supervised anomaly search with the CATHODE method. Expected discovery potentials and exclusion limits are shown for 140 fb${}^{-1}$ of 13 TeV proton-proton collisions at the LHC.

    hep-phPRD(2026)·9 citations
23. 23*

    Unlocking time-dependent $CP$ violation without signal vertexing at $B$ factories

    Mirco Dorigo🇮🇹 · Sebastiano Raiz🇩🇪 · Diego Tonelli🇮🇹 · Radek Zlebcik🇨🇿

    We present a method to measure time-dependent $CP$ violation in $B^0$ decays produced in ${\rm Y}(4S)\to B^0{\overline{B}}^0$ events at $B$ factories without reconstructing the signal decay vertex. The method exploits the sensitivity of the tag ${\overline{B}}^0$ decay time to $CP$ violation in the $B^0$ signal. It relies on a compact $e^{+}{e}^{-}$ interaction region and excellent vertex resolution, which enable precise measurement of the displacement between production and decay vertices of the tag meson. We study an application to $B^0\to {\pi }^0{\pi }^0$ decays using a simplified simulation that approximates the conditions of the Belle II experiment at the SuperKEKB collider. Our approach achieves a sensitivity on mixing-induced $CP$ violation that would require 20 times larger samples with standard approaches. When incorporated into the $B\to \pi \pi$ isospin analysis, the expected results would reduce the degeneracy of ${\varphi }_2$ solutions and significantly increase precision. This work opens a path to previously inaccessible $CP$-violation studies enhancing and accelerating the reach of Belle II and future flavor physics programs.

    hep-phhep-exPRD(2025)·2 citations
24. 24*

    Phase transitions in a holographic superfluid model with non-linear terms beyond the probe limit

    Zi-Qiang Zhao🇺🇸 · Zhang-Yu Nie🇨🇳 · Jing-Fei Zhang🇺🇸 · Xin Zhang🇺🇸

    We study the holographic s-wave superfluid model with 4th and 6th power self-interaction terms $\lambda |\psi {|}^4$ and $\tau |\psi {|}^6$ with considering the full back-reaction of the matter fields on the metric in the 3+1 dimensional bulk. The self-interaction terms are good at controlling the condensate to realize various phase transitions, such as the zeroth-order, first-order, and second-order phase transitions within the single condensate s-wave superfluid model. Therefore, in this work, we are able to investigate the influence of the back-reaction strength on the various phase transitions, including the zeroth and first order phase transitions. In addition, we confirm that the influence of the 4th and 6th power terms on the superfluid phase transition in the case of finite back-reaction are qualitative the same as in the probe limit, thus present universality. We also plot the special value ${\lambda }_s$ of the parameter $\lambda$ at different back-reaction strength, below which the condensate grows to an opposite direction and is important in controlling the order of the superfluid phase transitions. Comparing the influence of the back-reaction parameter and that of the higher-order nonlinear coefficients, we see that the back-reaction strength brings in both the effective couplings similar to the 4th power and 6th power terms.

    hep-phastro-ph.COgr-qchep-thEPJC(2025)·9 citations
25. 25*

    Novel method to trace the dark matter density profile around supermassive black holes with AGN reverberation mapping

    Mayank Sharma🇺🇸 · Gonzalo Herrera🇺🇸 · Nahum Arav🇺🇸 · Shunsaku Horiuchi🇺🇸

    We propose a new method to determine the dark matter density profile in the vicinity of distant supermassive black holes (SMBH) using reverberation mapping (RM) measurements of active galactic nuclei (AGN). The mapping of multiple emission lines allows the measurement of the enclosed mass within different radii from the central SMBH, which can be used to infer or constrain the dark matter density profile on sub-parsec scales. We apply a toy model based on this method to a sample of fourteen AGN to test its feasibility based on current measurements. We find that for five objects, the observed enclosed mass does grow with radii, hinting towards the presence of a dark matter component at the 1-2 $\sigma$ level. For these sources, we find global evidence for a universal dark matter profile with a preferred radial steepness of index $\gamma \sim 1.6$, consistent with the scenario expected for a dark matter spike mildly relaxed by stellar heating processes. The enclosed dark matter mass, however, is found to be significantly larger than expected. We show that the current RM based mass measurements suffer from large systematic uncertainties, that limit the effectiveness of our method. Our work emphasizes the importance of applying the recent developments in mass determination techniques to target multiple emission lines with future RM and interferometry campaigns. This provides the most direct way of constraining the dark matter density in the sub-parsec regions around extragalactic SMBHs, which is crucial to our understanding of the dynamics and nature of dark matter.

    ↳ astro-ph.GAastro-ph.COhep-phPRD(2026)·9 citations
26. 26*

    Exploring Nonperturbative Behaviour of Moments and Cumulants in Quantum Theories

    Sebastian Schenk🇩🇪

    The dynamics of quantum fields become nonperturbative when their interactions are probed by a large number of particles. To explore this regime we study correlation functions which involve a large number of fields, focussing on massive scalar theories that feature arbitrary self-interactions, ${\varphi }^{2p}$. Treating quantum fields as operator-valued distributions, we investigate $n$-point correlation functions at ultra-short distances and compute moments and cumulants of fields, using a semiclassical saddle point approximation in the double scaling limit of weak coupling, $\lambda \to 0$, large quantum number, $n\to \infty$, while keeping $\lambda n$ constant. Addressing the nonperturbative regime, where $\lambda n\gtrsim 1$, requires a resummation of the effective saddle point to all orders in $\lambda n$. We perform this resummation in zero and one dimensions, and show that the moments, corresponding to correlation functions including disconnected contributions, grow exponentially with $n$. This growth is significantly reduced for higher-order self-interactions, i.e. for larger $p$. On the other hand, we argue that the cumulants, which represent connected correlation functions, grow even more rapidly and are mostly independent of $p$.

    ↳ hep-thhep-phPRD(2025)·1 citation
27. 27*

    Analytical solutions of CPT-odd Maxwell equations in Schwarzschild spacetime

    Hao Wang🇨🇳 · Zhi Xiao🇨🇳 · Bing Sun🇨🇳

    In this work, we present the CPT-violating (CPTV) Maxwell equations in curved spacetime using the Newman-Penrose (NP) formalism. We obtain a semi-analytical solution to the Maxwell equations in Schwarzschild spacetime under the assumption that the CPT-odd ${\left(k_{AF}\right)}^{\mu }$ term exhibits spherical symmetry in the Schwarzschild background. Retaining only terms up to linear order in the ${\left(k_{AF}\right)}^{\mu }$ coefficient, we obtain perturbative solutions by treating the solutions of the Lorentz-invariant Maxwell equations as the zeroth-order approximation and incorporating the ${\left(k_{AF}\right)}^{\mu }$ terms as an additional source term alongside the external charge current. Each resulting NP scalar field can be factorized into two components: the radial component is expressed in terms of hypergeometric functions, while the angular component is described by spin-weighted spherical harmonics.

    ↳ gr-qchep-phCPC(2025)·1 citation
28. 28*

    Differential Space of Feynman Integrals: Annihilators and $\mathcal{D}$-module

    Vsevolod Chestnov🇮🇹 · Wojciech Flieger🇮🇹 · Pierpaolo Mastrolia🇮🇹 · Saiei-Jaeyeong Matsubara-Heo🇯🇵 · Nobuki Takayama🇯🇵 · William J. Torres Bobadilla🇬🇧

    We present a novel algorithm for constructing differential operators with respect to external variables that annihilate Feynman-like integrals and give rise to the associated $\mathcal{D}$-modules, based on Griffiths-Dwork reduction. By leveraging the Macaulay matrix method, we derive corresponding relations among partial differential operators, including systems of Pfaffian equations and Picard-Fuchs operators. Our computational approach is applicable to twisted period integrals in projective coordinates, and we showcase its application to Feynman graphs and Witten diagrams. The method yields annihilators and their algebraic relations for generic regulator values, explicitly avoiding contributions from surface terms. In the cases examined, we observe that the holonomic rank of the $\mathcal{D}$-modules coincides with the dimension of the corresponding de Rham co-homology groups, indicating an equivalence relation between them, which we propose as a conjecture.

    ↳ hep-thhep-phmath-phmath.MPPLB(2025)·6 citations
29. 29*

    On Chaos in QFT

    Jacob Sonnenschein🇮🇱 · Nadav Shrayer🇮🇱

    In this note we explore the chaotic behavior of non-integrable QFTs and compare them to integrable ones. We choose as prototypes the double sine-Gordon and the sine-Gordon models. We analyze their discrete spectrum determined by a truncation method. We examine the map of the corresponding energy eigenvalues to the eigenvalues of the random matrix theory (RMT) Gaussian orthogonal ensemble (GOE). This is done by computing the following properties: (a) The distribution of the adjacent spacings and their ratios (b) Higher order spacings and ratios (c) Pair correlations (d) Spectral form factors and (e) Spectral rigidity. For these properties we determine the differences between the integrable and non-integrable theories and verify that the former admits a Poisson behavior and the latter GOE (apart from the spectral rigidity).

    ↳ hep-thhep-phnlin.CDPRD(2026)·3 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.