Mon·Aug 11, 2025Monday·August 11, 2025

1. 01*

   Space-time Areas and Hadronization Studies

   S. Abachi🇺🇸 · C. Buchanan🇺🇸

   Space-time area laws play a fundamental role in modeling strongly interacting phenomena, such as in relativistic string models, QCD on the lattice, and in hadronization modeling. For the latter, an exact expression for relevant space-time areas related to the final state hadronic events for hadrons of any mass is calculated. Usage of this expression in the UCLA hadronization model helps validate its space-time area law (STAL) principle and unifies the treatment of heavy and light hadrons via a single fragmentation function.

   hep-phhep-exnucl-exnucl-th0 citations
2. 02*

   Neutrino fog in the light dark sector: the role of isospin violation

   Víctor Martín Lozano🇪🇸 · Shankar Pramanik🇮🇳 · Soumya Sadhukhan🇮🇳 · Adrián Terrones🇪🇸

   Dark matter (DM) direct detection is now standing at an interesting juncture, where the Standard Model (SM) neutrino background and the upper bound on the DM signal cross section are starting to overlap in the DM mass region around 10 GeV. The neutrino floor, which defines the extent of the neutrino background, can be modified in different Beyond Standard Model (BSM) setups. We work in a simple BSM dark sector extension of the SM visible sector, where isospin-violating interactions occur naturally. In this model, both DM and neutrinos have, in general, isospin-violating (IV) interactions with nuclei, through a newly added local U(1) gauge boson $Z^{\prime }$. Depending on the choice of the model parameters, the coherent elastic neutrino-nucleus scattering (CE$\nu$NS) cross section can either increase or decrease, shifting up or down the neutrino floor in the parameter space. The same is true for the DM experimental upper bound, whose change is driven exclusively by the IV parameter $f_n/f_p$. Several scenarios are constructed, based on the interplay between the two regions and the allowed parameter space left between them, and discussed. The potential observation of solar neutrinos in DM direct detection experiments is also discussed in the context of our framework.

   hep-ph2 citations
3. 03*

   Correlation functions for $n{\bar{D}}_{s1}(2460)$ and $n{\bar{D}}_{s1}(2536)$

   Breno Agatão🇧🇷 · Pedro Brandão🇧🇷 · A. Martinez Torres🇧🇷 · K. P. Khemchandani🇧🇷 · Luciano M. Abreu🇧🇷 · E. Oset🇪🇸

   We study the interaction of the $n{\bar{D}}_{s1}(2460)$ and $n{\bar{D}}_{s1}(2536)$ systems from the perspective that the $D_{s1}(2460)$ and $D_{s1}(2536)$ states are molecular states of $K{D}^{\ast }$ and $K^{\ast }D$, respectively. We use an improved version of the fixed center approximation to the Faddeev equations which fulfills exact elastic unitarity at the threshold of the systems. We predict the existence of resonant states below threshold and also determine the scattering length, effective range and correlation functions of these systems, showing that the results contain important information to test the assumed molecular nature of the two $D_{s1}$ states.

   hep-phnucl-thEPJC(2025)·13 citations
4. 04*

   Detecting Traces of Light-Quark Yukawa Couplings to the Higgs Boson in Fragmentation Products

   Johannes K. L. Michel🇳🇱

   We point out that Yukawa interactions of light quarks with the Higgs boson are imprinted as unique azimuthal modulations in the density of fragmentation hadrons relative to the Higgs $p_T$. We introduce Yukawa Fragmentation Asymmetries (YFAs), interference observables that are linearly proportional to real (Standard Model) or CP-odd Yukawa couplings, respectively. The chiral suppression is lifted nonperturbatively by chiral-odd multi-hadron fragmentation functions. As a simple example process, we consider $VH$ production with a tagged target fragmentation hadron at the HL-LHC. We find promising projected sensitivities to first and second-generation couplings while maintaining superior control over theory systematics, flavor separation, and model independence compared to present methods. Our results point to deep synergies between precision studies of confinement and the in-depth exploration of the Higgs sector.

   hep-phhep-exnucl-exnucl-th3 citations
5. 05*

   Models for the Electric Dipole Moment and Anomalous Magnetic Moment of the Tau Lepton

   Yuichiro Nakai🇨🇳 · Yoshihiro Shigekami🇨🇳 · Peng Sun🇨🇳 · Zhihao Zhang🇨🇳

   The Belle II experiment and other ongoing and projected lepton facilities are expected to greatly enhance the sensitivity to the electric dipole moment (EDM) and anomalous magnetic moment ($g-2$) for the tau lepton, making it timely to explore models that predict these observables. We present a class of models that generate a sizable EDM and $g-2$ of the tau lepton via radiative tau mass generation. Two benchmark models with different hypercharge assignments are investigated. The first model contains neutral fermions and charged scalars. We find that the model can predict a large signal of the tau EDM, $d_{\tau }=\mathcal{O}(10^{-19})e\mathrm{cm}$, and $g-2$, $a_{\tau }=\mathcal{O}(10^{-5})$, which are within the reach of future updates of their measurements. In contrast, the second model, containing a charged fermion and neutral scalars, yields a similar magnitude for the $g-2$ but predicts a comparatively smaller EDM signal. Our models serve as benchmarks for new physics generating sizable EDM and $g-2$ of the tau lepton.

   hep-phhep-exPRD(2026)·9 citations
6. 06*

   Illuminating Scalar Dark Matter Co-Scattering in EFT with Monophoton Signatures

   Geneviève Bélanger🇫🇷 · Manimala Mitra🇮🇳 · Rojalin Padhan🇰🇷 · Abhishek Roy🇰🇷

   We investigate the co-scattering mechanism for dark matter production in an EFT framework which contains new $Z_2$-odd singlets, namely two fermions $N_{1,2}$ and a real scalar $\chi$. The singlet scalar $\chi$ is the dark matter candidate. The dimension-5 operators play a vital role to set the observed DM relic density. We focus on a nearly degenerate mass spectrum for the $Z_2$ odd particles to allow for a significant contribution from the co-scattering or co-annihilation mechanisms. We present two benchmark points where either of the two mechanisms primarily set the DM relic abundance. The main constraint on the model at the LHC arise from the ATLAS mono-$\gamma$ search. We obtain the parameter space allowed by the observed relic density and the mono-$\gamma$ search after performing a scan over the key parameters, the masses $M_{N_{1,2}},M_{\chi }$ and couplings $c_3^{\prime },y_{11,22}^{\prime }$. We find the region of parameter space where the relic abundance is set primarily by the co-scattering mechanism while being allowed by the LHC search. We also determine how the model can be further probed at the HL-LHC via the mono-$\gamma$ signature.

   hep-phastro-ph.COJHEP(2026)·3 citations
7. 07*

   Mass Spectrum of Heavy Mesons using WKB Approximation

   Bhaskar Jyoti Hazarika🇮🇳 · Tanmay Dev🇮🇳

   In this study, we analyze the bound-state energy spectrum of quark-antiquark systems using the semiclassical WKB approximation. We consider the Cornell potential, which combines a linear confinement term with a Coulombic interaction, and perform a Taylor series expansion around an appropriately chosen point $r_0$ to simplify the potential near the classical turning points. This expansion enables an analytic treatment of the Schrödinger equation within the leading-order WKB framework. The resulting quantization condition yields approximate energy levels that capture the essential dynamics of quarkonium systems and illustrate the utility of the WKB method in modeling hadronic bound states.

   hep-phInt.J.Mod.Phys.A(2025)·2 citations
8. 08*

   Semi-inclusive deep inelastic scattering off a tensor-polarized spin-1 target

   Jing Zhao🇨🇳 · Alessandro Bacchetta🇮🇹 · Shunzo Kumano🇨🇳 · Tianbo Liu🇨🇳 · Ya-jin Zhou🇨🇳

   We investigate the semi-inclusive deep inelastic scattering off a tensor-polarized spin-1 target, focusing on the production of an unpolarized hadron. The complete differential cross section is expressed in terms of 23 structure functions, which depend on the spin states of the target and the azimuthal modulations of the final-state hadron. Within the transverse momentum dependent (TMD) factorization framework, we derive the hadronic tensor using quark-quark correlators and quark-gluon-quark correlators up to twist-3. At tree-level, 21 nonvanishing structure functions are obtained at the leading and subleading twist, expressed as convolutions of TMD parton distribution functions and TMD fragmentation functions. The measurement of these nonzero structure functions can be utilized to explore the tensor-polarized structure of spin-1 particles, offering insights into their internal dynamics.

   hep-phJHEP(2025)·7 citations
9. 09*

   Drell--Yan lepton pair production at low invariant masses: transverse-momentum resummation and non-perturbative effects in QCD

   Stefano Camarda🇨🇭 · Giancarlo Ferrera🇮🇹 · Lorenzo Rossi🇮🇹

   We consider the transverse-momentum ($q_T$) distribution of Drell-Yan lepton pairs produced with invariant masses ($M$) from low values up to the $Z$-boson peak ($4\le M\le 116$~GeV). We present perturbative predictions obtained by consistently combining the resummation of logarithmically enhanced QCD corrections at small $q_T$ ($q_T\ll M$) up to next-to-next-to-next-to-next-to-leading logarithmic accuracy with the available fixed-order calculations at next-to-next-to-leading order (i.e. $\mathcal{O}({\alpha }_S^3)$) valid at large $q_T$. For very low $q_T$ ($q_T\sim {\Lambda }_{\mathrm{QCD}}$), non-perturbative (NP) QCD effects become dominant and have been included through a NP form factor with a small number of free-parameters. We compare our results with multiple experimental datasets from hadron colliders, finding excellent agreement between theory and data. By fitting the NP parameters, we achieve a precise extraction of the NP form factor and the so-called Collins-Soper kernel.

   hep-phhep-latJHEP(2026)·16 citations
10. 10*

    The Free Massive Quadratic Action from the Exotic Model (E7)

    John A. Dixon🇨🇦

    The Exotic Model arises from adding a special exotic invariant to the Supersymmetric Standard Model. The Exotic Model has a supersymmetry violating mass spectrum without using spontaneous or explicit breaking of supersymmetry. The splitting arises with gauge symmetry breaking, at tree level, in the supermultiplets of the Z vector boson and a new X vector boson. It spreads to the other particles at one loop. This mass splitting is possible because the exotic invariant changes the algebra of supersymmetry. This paper E7 discusses a number of issues that arise in the calculation of the mass splitting of the Exotic Model. That mass splitting will require computer programs for solution.

    hep-ph4 citations
11. 11*

    Illuminating Degenerate Dark Sector of Inert Doublet Model at Muon Collider

    Anupam Ghosh🇮🇳 · Partha Konar🇮🇳 · Chandrima Sen🇮🇳 · Bhavya Thacker🇮🇳

    The Inert scalar Doublet Model (IDM) presents a simple yet elegant framework for a scalar dark sector where the lightest mode functions as a viable dark matter candidate under a ${\mathbb{Z}}_2$ symmetry. With TeV-scale particles accessible to the Large Hadron Collider (LHC) or future colliders, probing different dark matter scenarios within IDM provides an exciting opportunity. While the Higgs portal dark matter scenario is extensively well-studied at the LHC, probing the degenerate scalar dark sector presents some unique challenges, not only in detecting excessively soft decay products and the tiny production cross-section expected at the higher masses. The present study explores the potential of a forward muon facility at a future muon collider to uncover this elusive degenerate dark sector.

    hep-ph5 citations
12. 12*

    Quarkonium Parton Shower in Herwig 7

    M.R. Masouminia🇬🇧 · P. Richardson🇬🇧

    We present the implementation of a fully automated quarkonium parton shower in Herwig 7, based on non-relativistic QCD (NRQCD) factorisation with spin-colour projections. The framework systematically incorporates colour-singlet and colour-octet production mechanisms, gluon fragmentation, and diquark production processes. Perturbative short-distance coefficients are combined with non-perturbative NRQCD matrix elements to simulate heavy-quark bound state formation. Splitting functions for $S$-, $P$- and $D$-wave states are explicitly derived and integrated into the angular-ordered shower evolution. The implementation preserves spin correlations and polarisation effects while accurately accounting for feed-down contributions. Results demonstrate improved agreement with the existing LHC data. This quarkonium parton shower will become publicly available with the release of Herwig-7.4.0.

    hep-phJHEP(2026)·3 citations
13. 13*

    $b\to c$ semileptonic sum rule: Current status and prospects

    Motoi Endo🇯🇵 · Syuhei Iguro🇯🇵 · Satoshi Mishima🇯🇵 · Ryoutaro Watanabe🇨🇳

    The $b\to c$ semileptonic sum rules provide relations between the decay rates of $B\to D^{(\ast )}\tau \bar{\nu }$ and ${\Lambda }_b\to {\Lambda }_c\tau \bar{\nu }$. Starting from the heavy quark and zero-recoil limits, we revisit the derivation of the sum rule for total decay rates. We then examine deviations from the limits and investigate corrections arising from realistic hadron masses and higher-order contributions to form factors, taking account of uncertainties. We show that these corrections are negligible compared to current experimental uncertainties, indicating that the sum rule is useful for cross-checking experimental consistency and testing the validity of the Standard Model predictions. In future, precise determinations of the form factors particularly for the tensor operator will be necessary to compare the sum rule predictions with ${\Lambda }_b\to {\Lambda }_c\tau \bar{\nu }$ data from the LHCb experiment and the Tera-Z projects.

    hep-phhep-exJHEP(2026)·6 citations
14. 14*

    Production of ${\pi }^{+}{\pi }^{-}$ pairs in diffractive photon-proton and in proton-proton collisions revisited, in particular concerning the Drell-Söding contribution

    Piotr Lebiedowicz🇵🇱 · Otto Nachtmann🇩🇪 · Antoni Szczurek🇵🇱

    We discuss the exclusive photoproduction of ${\pi }^{+}{\pi }^{-}$ pairs in photon-proton and in proton-proton collisions at high energies. The ${\rho }^0$, $\omega$, $f_2(1270)$, and non-resonant (Drell-Söding) contributions are considered. The calculation is based on the tensor-pomeron model. In the Drell-Söding contribution we have different subenergies for the ${\pi }^{+}p$ and ${\pi }^{-}p$ systems. In the method which we propose now we take this into account. Respecting the gauge-invariance constraints is then a nontrivial problem for which, however, we present a solution here. In the present paper we give in this way a substantial improvement of the calculations for real photoproduction of ${\pi }^{+}{\pi }^{-}$ from JHEP 01, 151 (2015), and we extend the calculations to low $Q^2$ electroproduction, $0⩽Q^2⩽0.5$ GeV${}^2$. The photo- and electroproduction amplitudes are then the basis for the calculation of central exclusive production (CEP) of ${\pi }^{+}{\pi }^{-}$ pairs in $pp$ collisions, where at least one proton participates in the CEP via a virtual-photon emission. The revised model leads to enhanced cross sections and gives an increased skewing of the ${\rho }^0$ spectral shape. For the $pp\to pp{\pi }^{+}{\pi }^{-}$ reaction, we calculate differential cross sections as function of the two-pion invariant mass, pion transverse momentum and pion pseudorapidity. This research is relevant in the context of ALICE, ATLAS, CMS, and LHCb measurements in $pp$ collisions. Our results can also serve as basis for the description of coherent ${\pi }^{+}{\pi }^{-}$ production in ultra-peripheral $p$A and AA collisions at the LHC. The formulas given in our paper can be used for the analysis of photoproduction and small-$Q^2$ electroproduction in $ep$ collisions at high energies. Such data exist from the HERA experiments and will be obtained in the future at the electron-ion colliders.

    hep-phhep-exJHEP(2026)·2 citations
15. 15*

    Dark Sector Electroweak Baryogenesis In Light Of The Galactic Center Excess

    Jean-Samuel Roux🇨🇦 · James M. Cline🇨🇦

    We revisit a model of electroweak baryogenesis that includes a dark matter candidate, and sequesters the new CP violation required to produce the baryon asymmetry in a dark sector. The model can explain the baryon asymmetry, dark matter relic density, and the long-standing excess of gamma rays from the galactic center. The first order electroweak phase transition induced by the new physics can give rise to gravitational waves that may be observed in future experiments. The model predicts dark matter signals in direct detectors, and a significant contribution to the Higgs boson invisible decay width.

    hep-phastro-ph.COastro-ph.HEPRD(2025)·2 citations
16. 16*

    Prompt atmospheric leptons and the potential role of intrinsic charm

    Laksha Pradip Das🇺🇸 · Diksha Garg🇺🇸 · Maria Vittoria Garzelli🇩🇪 · Mary Hall Reno🇺🇸 · Günter Sigl🇩🇪

    The all-sky very-high energy ($10^4-10^6$ GeV) atmospheric muon flux is most recently measured by IceCube, where in the higher energy range, the spectrum hardens indicating a prompt component. IceCube also measures the atmospheric muon neutrino flux at high energy. Since this is dominated by the astrophysical flux, they are only able to set an upper bound on the prompt atmospheric muon neutrino flux contribution. We provide a new evaluation of the prompt atmospheric muon flux including for the first time an intrinsic charm component to colliding nucleons. This increases forward production of ${\bar{D}}^0$, $D^{-}$ and ${\Lambda }_c$ which decay into final states that can contain muons and muon neutrinos. We show how the increase in the prompt muon flux due to intrinsic charm has an associated increase in the prompt muon neutrino flux. We consider the Regge ansatz for intrinsic charm production that we implement in MCEq used for the calculation of the lepton fluxes. We discuss the challenges of obtaining predictions that are simultaneously consistent with both IceCube's high energy atmospheric muon flux measurements and their upper bound on the prompt muon neutrino flux. We quantify the discrepancies.

    hep-phPoS(2025)·3 citations
17. 17*

    QED-enhanced PDF implications for the Higgs sector

    Amanda M. Cooper-Sarkar🇬🇧 · Thomas Cridge🇧🇪 · T. J. Hobbs🇺🇸 · Joey Huston🇺🇸 · Pavel Nadolsky🇺🇸 · Maximiliano Ponce-Chavez🇺🇸 · Keping Xie🇺🇸

    In this work, we examine the implications of electroweak corrections beyond leading order for processes of special interest in the Higgs sector. We especially explore the role of these corrections given the introduction of an explicit parton distribution function (PDF) for the photon in the proton, an object which emerges necessarily in global PDF fits which include QED effects (i.e., QED-enhanced PDFs). We concentrate on several representative cases, including total Higgs-production cross sections through gluon fusion, $gg\to H$, vector-boson fusion (VBFH), and associated production, $pp\to VH$; we also examine differential distributions, taking a representative Higgs-strahlung process, $pp\to W^{+}H$. We find that the recently developed LUX formalism for the photon PDF significantly stabilizes the PDF dependence of both QED-PDF and electroweak corrections in the Higgs sector, while leaving overall $\sim 3-4\%$ cross-section-level variations, depending on the chosen QED-enhanced PDF. We illustrate this QED-enhanced PDF dependence by exploring predictions based upon recent analyses of the CTEQ-TEA, MSHT, and NNPDF analysis groups, fitted either at NNLO or approximate N3LO in QCD.

    hep-phJHEP(2026)·4 citations
18. 18*

    Wigner Phase-Space Densities of Nuclear Clusters and Hypernuclei

    Jiaxing Zhao🇩🇪 · Joerg Aichelin🇫🇷 · Elena Bratkovskaya🇩🇪

    We solve the Schrödinger equation for few-body systems to obtain the wave function for light nuclear clusters and hypernuclei from d to ${}_{\mathrm{\Lambda \Lambda }}^5\mathrm{He}$ employing realistic nucleon-nucleon and nucleon-$\Lambda$ potentials. We project the solution to the hyperspherical harmonic basis states to obtain the corresponding density matrices and the Wigner densities. The experimental root mean square (rms) radii and binding energies of the different clusters are well reproduced. The Wigner densities obtained will allow to improve the present coalescence approaches to identify clusters, created in heavy-ion collisions.

    ↳ nucl-thhep-phPRC(2025)·4 citations
19. 19*

    Illuminating Hidden Pulsars: Scintillation-Enhanced Discovery of Two Binary Millisecond Pulsars in M13 with FAST

    Dejiang Yin · Lin Wang🇨🇳 · Li-yun Zhang🇨🇳 · Lei Qian · Baoda Li🇨🇳 · Kuo Liu🇩🇪 · Bo Peng · Yinfeng Dai · Yaowei Li🇨🇳 · Zhichen Pan

    We conducted a sensitive acceleration search using Fast Fourier Transform (FFT) techniques on full-length and segmented data from 84 observations of the globular cluster M13 with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Employing a low detection threshold (2 $\sigma$) to maximize sensitivity to faint pulsars, here we report the discovery of two binary millisecond pulsars: J1641+3627G (M13G) and J1641+3627H (M13H). Both pulsars were detected during scintillation-brightened states, revealing systems that would otherwise remain undetected. For M13G, we obtained a phase-connected timing solution spanning 6.4 years, identifying it as a black widow system with an orbital period of 0.12 days hosting an extremely low-mass companion ($\sim 9.9\times 10^{-3}{M}_{\odot }$), though no eclipses were observed. M13H, however, shows significant apparent acceleration but was detected in only 2 of 84 observations; its extremely low detection rate currently prevents constraints on orbital parameters or classification.

    ↳ astro-ph.HEhep-phApJ(2025)·2 citations
20. 20*

    Realistic shell model for ordinary muon capture of sd-shell nuclei

    S. L. Lyu🇮🇹 · G. De Gregorio🇮🇹 · T. Fukui🇯🇵 · N. Itaco🇮🇹 · L. Coraggio🇮🇹

    We report about a study of the ordinary muon capture in nuclei belonging to the sd shell, an electroweak process that occurs with exchange momenta far larger than ordinary beta decays (approximately 100 MeV). Such a characteristic places this transition in an energy range that is consistent with the neutrinoless double-beta decay, and represents an interesting test for nuclear models to support their predictions of the nuclear matrix elements for such an unobserved process. For the first time, the calculations are carried out within the realistic shell model (RSM), namely employing effective shell-model Hamiltonians and decay operators derived from realistic nuclear forces, without resorting to any empirical adjustment of the coupling constants. This is a chapter of a research program that is aimed to assess the realistic shell model in reproducing the observables related to electroweak processes in nuclei, and then to evaluate the reliability of nuclear matrix elements for the neutrinoless double-beta decay that are calculated within this approach. We calculate the partial capture rates for many nuclear systems in the sd-shell region, as well as their spectroscopic properties, and compare the results with the available experimental counterparts. Such a comparison tests the relevance of a microscopic approach to the renormalization of transition operators to reproduce data and provide solid predictions of unknown observables.

    ↳ nucl-thhep-exhep-phnucl-exPRC(2025)·2 citations
21. 21*

    Event Rates at a 10 TeV Muon Collider and Implications for Detector Design: Trigger, Data Acquisition, and Luminosity

    Tova Holmes🇺🇸 · Lawrence Lee🇺🇸

    This short document presents a discussion of rates of a wide range of processes at a muon collider. The goal is to provide a first look at what will fill the detector, how often processes of interest are occurring, and the implications for detector readout, a potential trigger system, and luminosity measurements.

    ↳ hep-exhep-ph1 citation

* 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.