Thu·Jan 16, 2025Thursday·January 16, 2025

1. 01*

   Scaling of the elastic proton-proton cross-section

   Michał Praszałowicz🇵🇱 · Cristian Baldenegro🇮🇹 · Christophe Royon🇺🇸 · Anna M. Staśto🇺🇸

   We discuss scaling properties of the elastic $pp$ cross-section both at the ISR and the LHC. We observe that the ratio of bump to dip positions of the differential cross-section $d{\sigma }_{\mathrm{el}}/dt$ is constant over a wide energy range. We next study the consequences of this property, including geometric scaling at the ISR and new scaling laws at the LHC.

   hep-phActa Phys.Polon.Supp.(2025)·1 citation
2. 02*

   Impact of New Physics on Momentum-Dependent Particle Widths and Propagators

   Christoph Englert🇬🇧 · Wrishik Naskar🇬🇧 · Michael Spannowsky🇬🇧

   We investigate the impact of momentum-dependent particle widths and propagators on gauge and Higgs bosons and the top quark within the Standard Model (SM) and its SMEFT extensions near thresholds. By incorporating self-energy corrections via Dyson resummation, we quantify deviations from the fixed-width approximation and assess their implications for collider observables. While effects on the Higgs boson are negligible and the $W$ boson shows percent-level deviations in reconstructed transverse mass distributions, the top quark exhibits significant sensitivity near its mass threshold. Future lepton colliders, e.g., electron-positron machines or muon colliders, can offer sensitivity to these effects, enabling constraints on SMEFT Wilson coefficients. We perform a representative case study for the precision frontier available with a staged future muon collider. Our results highlight that momentum dependencies can provide additional sensitivity at precision-era experiments, enhancing the potential for discovering new physics there.

   hep-phhep-exPRD(2025)·3 citations
3. 03*

   Semileptonic $B_{(s)}$ meson decays to $D_0^{\ast }(2300),D_{s0}^{\ast }(2317),D_{s1}(2460),D_{s1}(2536),D_1(2420)$ and $D_1(2430)$ within the covariant light-front approach

   You-Ya Yang🇨🇳 · Zhi-Qing Zhang🇨🇳 · Hao Yang🇨🇳

   In this work, we investigate the semileptonic decays of $B_{(s)}$ meson to $D_0^{\ast }(2300)$, $D_{s0}^{\ast }(2317)$, $D_{s1}(2460)$, $D_{s1}(2536)$, $D_1(2420)$ and $D_1(2430)$ in the covariant light-front quark model (CLFQM). We combine the helicity amplitudes via the corresponding form factors to obtain the branching ratios of the semileptonic decays $B_{(s)}\to D_{(s)}^{\ast \ast }\ell {\nu }_{\ell }$ with $D_{(s)}^{\ast \ast }$ referring to a P-wave exicted charmed meson $D_0^{\ast }(2300)$, $D_{s0}^{\ast }(2317)$, $D_{s1}(2460)$, $D_{s1}(2536)$, $D_1(2420)$ or $D_1(2430)$ and $\ell =e,\mu ,\tau$. Furthermore, we also take into account another two physical observables, namely the longitudinal polarization fraction $f_L$ and the forward-backward asymmetry $A_{FB}$. Most of our predictions are comparable to the results given by other theoretical approaches and the present available data. The branching ratios of the semileptonic decay channels $B_s\to D_{s1}(2460)\ell {\nu }_{\ell }$ and $B\to D_1(2420)\ell {\nu }_{\ell }$ are larger than those of the semileptonic decays $B_s\to D_{s1}(2536)\ell {\nu }_{\ell }$ and $B\to D_1(2430)\ell {\nu }_{\ell }$, respectively. We find that the long-standing '$1/2$ vs $3/2$ puzzle' in the decays $B^{+}\to {\bar{D}}_1^{(\prime )0}{\ell }^{\prime +}{\nu }_{{\ell }^{\prime }}$ $({\ell }^{\prime }=e,\mu )$ can be solved by taking some negative mixing angle ${\theta }_s$ values within a range from $-30.3^{\circ }$ to $-24.9^{\circ }$, corresponding to $\theta$ of about $5^{\circ }\sim 10.4^{\circ }$. While Belle collaboration updated their measurements for the decays $B^0\to D_0^{\ast -}{\ell }^{\prime +}{\nu }_{{\ell }^{\prime }}$ with only a small upper limit $Br(B^0\to D_0^{\ast -}{\ell }^{\prime +}{\nu }_{{\ell }^{\prime }})<0.44\times 10^{-3}$ obtained, which is much larger than most theoretical predictions and causes a new puzzle.

   hep-phhep-ex1 citation
4. 04*

   Prospects of $Z^{\prime }$ Portal Dark Matter in $U(1{)}_{L_{\mu }-L_{\tau }}$

   Zhen-Wei Wang🇨🇳 · Zhi-Long Han🇨🇳 · Fei Huang🇨🇳 · Yi Jin🇨🇳 · Honglei Li🇨🇳

   The gauged $U(1{)}_{L_{\mu }-L_{\tau }}$ model is well-motivated to explain the muon $g-2$ anomaly and dark matter in previous studies. However, the latest NA64$\mu$ experiment has almost excluded all the parameter space for the muon $g-2$, which indicates that the light dark matter benchmark scenarios interpreting muon $g-2$ in previous studies are also not allowed at present. In light of many recent and future experimental results, we revisit the minimal $Z^{\prime }$ portal dark matter in $U(1{)}_{L_{\mu }-L_{\tau }}$. Focus on the phenomenology of dark matter $\chi$, we first explore the viable parameter space for the light dark matter under various tight constraints. Around the $Z^{\prime }$ resonance, we find that there is still a large parameter space for $m_{\chi }\gtrsim 10$ MeV via thermal freeze-out. On the other hand, the constraints on $Z^{\prime }$ above the electroweak scale are quite loose but are less studied for dark matter. We also investigate the heavy dark matter around the TeV scale and corresponding constraints. A large part of the parameter space for dark matter is within the reach of future experiments.

   hep-phPRD(2025)·9 citations
5. 05*

   Scotoseesaw mechanism from a $Z_3$ symmetry of matter

   Doan Minh Luong🇻🇳 · Phung Van Dong🇻🇳

   We show that the neutrino mass generation and the dark matter stability can be governed by the center of the QCD group, which is a $Z_3$ group. Three right-handed neutrinos $N_{1,2,3R}$ transform under $Z_3$ as $1,w,w^2$, where $w=e^{i2\pi /3}$ is the cube root of unity, and they couple to usual lepton doublets via the usual Higgs doublet $H$ and two new scalar doublets $\eta ,\chi$, which transform under $Z_3$ as $1,w^2,w$, respectively. This leads to a scotoseesaw mechanism in which the seesaw and scotogenic neutrino mass generations are induced by the Majorana $N_{1R}$ mass and the Dirac $N_{2,3R}$ mass, respectively. Although the lightest of the $Z_3$ fields is stabilized, responsible for dark matter, the model lacks an explanation for relic density and/or direct detection. The issue can be solved in a $U(1{)}_{B-L}$ gauge completion of the model, for which the center of the QCD group is isomorphic to $Z_3=\{1,T,T^2\}$ for $T=w^{3(B-L)}$.

   hep-phhep-thEPJC(2025)·3 citations
6. 06*

   Are there critical aspects in the time, energy and angular distributions of SN1987A?

   Veronica Oliviero🇮🇹 · Riccardo Maria Bozza🇮🇹 · Vigilante di Risi🇮🇹 · Giuseppe Matteucci🇮🇹 · Giulia Ricciardi🇮🇹 · Francesco Vissani🇮🇹

   Supernova neutrinos are of considerable importance for ongoing research in astrophysics, nuclear and particle physics. Existing simulations of this complex event are increasingly sophisticated, but the accuracy with which they describe the emission is unknown. The only event observed so far with neutrino telescopes, SN1987A, still plays a crucial role and deserves to be studied meticulously. With this in mind, we have undertaken a refined analysis of the observations, taking into account the knowledge gained over the past decades. In this work, we consider a new parameterised model of electron antineutrino emission and test its adequacy in describing the observed distributions of energy, time and angle. The values of the model parameters derived from the data and their uncertainty intervals are presented and their significance is discussed.

   hep-phJ.Phys.Conf.Ser.(2025)·0 citations
7. 07*

   Quarkonium dynamics in the quantum Brownian regime with non-abelian quantum master equations

   Aoumeur Daddi Hammou🇫🇷 · Stéphane Delorme🇵🇱 · Jean-Paul Blaizot🇫🇷 · Pol-Bernard Gossiaux🇫🇷 · Thierry Gousset🇫🇷

   Quarkonium production in ultrarelativistic heavy ions collisions is one of the best probes of the QGP formed in these collisions. Resorting to accurate methods to describe the $Q\bar{Q}$ evolution in a QGP is a prerequisite for the precise interpretation of experimental data. Among these methods, the quantum master equations (QME) derived within the formalism of open quantum systems are particularly relevant. We present exact numerical solutions in a 1D setting of previously derived quantum master equations (QME) in their quantum Brownian regime. Distinctive features of the in-medium bottomonia evolution with the QME are presented; some phenomenological consequences are addressed by considering evolutions for a fixed as well as EPOS4 temperature profiles. Next, we investigate the accuracy of the semiclassical approximation (often used to describe charmonium production in URHIC) by benchmarking the corresponding evolutions on the exact solutions derived with the QME for the case of a $c\bar{c}$ pair.

   hep-phhep-thquant-phPoS(2025)·2 citations
8. 08*

   Form factors of light pseudoscalar mesons from the perturbative QCD approach

   Jian Chai🇨🇳 · Shan Cheng🇨🇳

   We study the electromagnetic and meson-photon transition form factors (TFF) of light pseudoscalar mesons from the perturbative QCD (pQCD) approach. To comprehensively account for both the longitudinal and transverse nonperturbative dynamics of hadronic constituents, we incorpoarate intrinsic transverse momentum distributions (iTMDs) alongside the conventional light-cone distribution amplitudes (LCDAs). The main motivations of this work are the disjointedness of electromagnetic form factors between the theoretical predictions and the experimental measurements, and the BaBar-Belle tension of pion-photon transition form factor in the large momentum transfers. Our calculation is carried out at the next-to-leading-order for the contributions from leading and subleading twist LCDAs, and leading order for the twist four contributions. Notably, this work presents the first systematic evaluation of higher-twist contributions to meson-photon TFFs. The key findings are: (a) iTMDs play a crucial role in describing form factor data, particularly in the small-to-intermediate momentum transfer region where they induce significant modifications to pQCD predictions. (b) The extracted transverse size parameters for valence quark states are found to be ${\beta }_{\pi }^2=0.51\pm 0.04$ GeV${}^{-2}$ and ${\beta }_K^2=0.30\pm 0.05$ GeV${}^{-2}$, the chiral mass of pion meson $m_0^{\pi }$ at $1$ GeV is determined to be $1.84\pm 0.07$ GeV. (c) The meson-photon TFFs are predominantly governed by leading-twist LCDAs. The iTMDs-enhanced pQCD results show better agreement with Belle's pion TFF data across intermediate and large momentum transfers and favor a small $\eta -{\eta }^{\prime }$ mixing angle. (d) Remarkably, the inclusion of iTMDs extends the applicability of pQCD calculations down to a few GeV${}^2$ for all considered form factors, significantly improving the theory-data consistency.

   hep-phJHEP(2025)·14 citations
9. 09*

   Entering the overcritical regime of nonlinear Breit-Wheeler pair production in collisions of bremsstrahlung $\gamma$-rays and superintense, tightly focused laser pulses

   I. Elsner🇩🇪 · A. Golub🇩🇪 · S. Villalba-Chávez🇩🇪 · C. Müller🇩🇪

   Near-future high-intensity lasers offer prospects for the observation of nonlinear Breit-Wheeler pair production in an overcritical field regime, where the quantum nonlinearity parameter substantially exceeds unity. This experimentally yet unexplored scenario is envisaged here to be reached via the collision of a tightly focused laser pulse with high-energy bremsstrahlung photons. We calculate the achievable number of pairs in a range of laser intensities around 10${}^{23}$ W/cm${}^2$ and GeV-energies of the incident bremsstrahlung-generating electron beam. We investigate under which conditions the attenuation of the $\gamma$-beam due to the production process must be taken into account and how much the second generation of created pairs contributes to the total yield. In the considered interaction regime, where the local production rate grows rather moderately with higher field intensities, it is shown that the range of mostly contributing bremsstrahlung frequencies is generally very broad. For sufficiently large values of the quantum nonlinearity parameter, an optimum domain of frequencies emerges which is located far below the spectral endpoint. Furthermore, we show that it is beneficial for achieving the optimum pair yield to increase the interaction volume by a wider laser focus at the expense of decreased field intensity.

   hep-phphysics.atom-phPRD(2025)·3 citations
10. 10*

    ${\Xi }_c(2790{)}^{+/0}$ and ${\Xi }_c(2815{)}^{+/0}$ radiative decays

    H. García-Tecocoatzi🇮🇹 · A. Ramirez-Morales🇲🇽 · A. Rivero-Acosta🇲🇽 · E. Santopinto🇮🇹 · C. A. Vaquera-Araujo🇲🇽

    In this work, we study the ${\Xi }_c$ baryon electromagnetic decay widths within the constituent quark model formalism through an analysis of the transitions from $P-$wave states to ground states. We use the non-relativistic limit of the Hamiltonian of the electromagnetic interaction on keeping all the terms up to the order $m_j^{-1}$. We calculate the electromagnetic decay widths analytically, for the first time, without any further approximation. Specifically, our theoretical results for the ${\Xi }_c(2790{)}^{+/0}$ and ${\Xi }_c(2815{)}^{+/0}$ radiative decay widths, without the introduction of any additional parameters, display a significant agreement with the recent experimental values obtained by the Belle experiment. The agreement is due to the fact that we have not introduced further approximation to simplify the calculation of the difficult convective term, unlike what was done in previous studies. Our predictions may be useful for future experiments at the Belle, BABAR, and LHC experiments.

    hep-phPLB(2025)·6 citations
11. 11*

    The 3D structure of the Nucleon in momentum space: TMD phenomenology

    Marco Radici🇮🇹

    I give a brief overview of our current understanding of the internal partonic 3D structure of nucleons in momentum space. I discuss some recent extractions of transverse-momentum-dependent distributions for quarks, whose analyses in the unpolarized case are reaching a theoretical precision comparable to collinear parton distribution functions. On the contrary, gluon transverse-momentum-dependent distributions are poorly known from a phenomenological point of view. I briefly review their general properties and sketch a recent model calculation covering all (un)polarized combinations at leading twist.

    hep-phActa Phys.Polon.Supp.(2025)·0 citations
12. 12*

    Fingerprinting New Physics with Effective Field Theories

    Jaco ter Hoeve🇬🇧

    Given the absence of direct evidence for new resonances beyond the Standard Model (BSM) at the Large Hadron Collider (LHC) so far, a complementary strategy to search for new physics in an indirect way is provided by the Standard Model Effective Field Theory (SMEFT). As the low-energy limit of a generic ultraviolet (UV) completion of the SM, the SMEFT provides a powerful theoretical framework to correlate deviations from the SM between different processes, offering experimental sensitivity to a plethora of SM extensions. This thesis presents a state-of-the-art SMEFT interpretation of the top, Higgs, diboson and electroweak sectors, taking into account data collected at the Large Electron-Positron Collider (LEP), the SLAC Large Detector (SLD) and the LHC. We also include the effect of the upcoming High-Luminosity LHC (HL-LHC) upgrade and demonstrate the unprecedented impact on the SMEFT parameter space of two proposed electron-positron colliders: the electron-positron Future Circular Collider (FCC-ee) and the Circular Electron Positron Collider (CEPC). We present constraints both in terms of Wilson coefficients, and couplings and masses of a wide range of UV-complete models through a newly developed automatised limit-setting procedure. We further present novel methodological advances through the development of unbinned multivariate likelihoods specialised to the SMEFT that provide maximal sensitivity to new physics using classification and regression techniques from Machine Learning. Our results provide an extensive characterisation of the SMEFT parameter space as probed both by current and future colliders, providing timely input to the upcoming European Strategy for Particle Physics Update.

    hep-ph1 citation
13. 13*

    Searches for ultralight vector and axion dark matter with KAGRA

    Yuta Michimura🇯🇵 · Takumi Fujimori🇯🇵 · Hiroki Fujimoto🇯🇵 · Tomohiro Fujita🇯🇵 · Kentaro Komori🇯🇵 · Jun'ya Kume🇮🇹 · Yusuke Manita🇯🇵 · Soichiro Morisaki🇯🇵 · Koji Nagano🇯🇵 · Atsushi Nishizawa🇯🇵 · Ippei Obata🇯🇵 · Yuka Oshima🇯🇵 · Hinata Takidera🇯🇵

    We have proposed using laser interferometric gravitational wave detectors to search for ultralight vector and axion dark matter. Vector dark matter can be probed through oscillating forces on suspended mirrors, while axion dark matter can be detected via oscillating polarization rotation of laser beams. This paper reviews these searches with the KAGRA detector in Japan, including the first vector dark matter search with KAGRA's 2020 data and installation of polarization optics for axion dark matter search during the upcoming 2025 observing run.

    hep-phastro-ph.IMphysics.optics2 citations
14. 14*

    Massive Helicity-Chirality Spinor Formalism from Massless Amplitudes with On-shell Mass Insertion

    Yu-Han Ni🇨🇳 · Yi-Ning Wang🇨🇳 · Chao Wu🇨🇳 · Jiang-Hao Yu🇨🇳

    We introduce a helicity-chirality spinor formalism to describe scattering amplitudes for particles of any masses and spins. The massive spin-spinors introduced by Arkani-hamed-Huang-Huang have been extended to the spin/helicity-transversality spinors, in which a new quantum number transversality, closely related to chirality, is introduced by extending the Poincare symmetry. The massive helicity-chirality amplitudes can be written by the large and small components of massless spinors $\lambda$ and $\eta$ following the $\lambda \sim \sqrt{E},\eta \sim \mathbf{m}/\sqrt{E}$ expansion order by order, which formulate the power counting rules of a large energy effective theory. Diagrammatically the mass expansion in amplitudes originates from the on-shell mass insertion: the helicity flip and chirality flip, which completely determines the three-point massive amplitudes. From the chirality-helicity unification at the UV, any massive helicity-chirality amplitude can be one-to-one corresponded to massless helicity amplitudes with (without) additional Higgs insertion. This UV-IR correspondence explains the mass enhancement in the weak decay processes ${\pi }^{+}\to {\mu }^{+}\nu$ and $t\to W^{+}b$, and isolates the correct UV of the three-point massive QED $F\bar{F}\gamma$ amplitudes in Arkani-hamed-Huang-Huang formalism. From massless-massive correspondence, the massless on-shell techniques can be utilized to construct higher-point massive amplitudes.

    hep-phhep-th6 citations
15. 15*

    Heavy neutral leptons and top quarks in effective field theory

    Rebeca Beltrán🇪🇸 · Giovanna Cottin🇨🇱 · Julian Günther🇩🇪 · Martin Hirsch🇪🇸 · Arsenii Titov🇮🇹 · Zeren Simon Wang🇹🇼

    We study the phenomenology of heavy neutral leptons (HNLs) at the LHC in effective field theory, concentrating on $d=6$ operators with top quarks. Depending on the operator choice and HNL mass, the HNLs will be produced either from proton-proton collisions in association with a single top, or via non-standard decays of top quarks. For long-lived HNLs we estimate the sensitivity reach of different detectors to various operators with top quarks and the HNLs for the high-luminosity phase of the LHC. For certain operators, ATLAS and some far detectors (MATHUSLA and ANUBIS) will be able to probe the associated new-physics scale as large as 12 TeV and 4.5 TeV, respectively, covering complementary HNL-mass ranges.

    hep-phJHEP(2025)·13 citations
16. 16*

    The LHC as a TeV Muon Beam Dump: Muonphilic Scalars at FASER

    Roshan Mammen Abraham🇺🇸 · Max Fieg🇺🇸

    The FASER experiment was designed to study long-lived dark sector particles and neutrinos traveling in the forward direction at the LHC. Neutrinos are predominantly produced from meson decays, which also result in an intense energetic flux of muons in the forward direction regularly observed by FASER. So far, these muons are treated only as backgrounds to neutrino and new physics studies, and extensive effort is required to suppress them. In this study, we consider the opposite scenario and use muons produced in the forward direction to produce new muonphilic scalars, which can then be searched for at the FASER detector. To minimize the backgrounds for this search, we make use of an upgraded preshower component, which is expected to be installed at FASER before the end of Run 3, and is capable of spatially resolving two energetic photons. We find that FASER, and its upgrade, FASER2 can probe currently unconstrained regions of parameter space, including regions that can potentially explain the $(g-2{)}_{\mu }$ anomaly. This highlights the physics opportunities that the intense TeV muon beam at the LHC can bring.

    hep-phhep-exPRD(2025)·10 citations
17. 17*

    Scalar Rayleigh Dark Matter: current bounds and future prospects

    Daniele Barducci🇮🇹 · Dario Buttazzo🇮🇹 · Alessandro Dondarini🇮🇹 · Roberto Franceschini🇮🇹 · Giulio Marino🇮🇹 · Federico Mescia🇮🇹 · Paolo Panci🇮🇹

    Dark Matter can interact with electroweak gauge bosons via higher-dimensional operators, in spite of being neutral under gauge interactions, much like neutral atoms interact with photons through Rayleigh scattering. This study explores effective interactions between a real scalar Dark Matter particle, singlet under the SM gauge group, and electroweak gauge bosons. We present a comprehensive analysis of current constraints and projected sensitivities from both lepton and hadron colliders as well as direct and indirect detection experiments in testing Rayleigh Dark Matter interactions. We find that, thanks to the complementarity between collider experiments and cosmological probes, thermally produced Rayleigh Dark Matter at the hundreds of GeV scale can be thoroughly tested with the next generation of experiments. For lighter candidates, upcoming forecasts will explore uncharted parameter space, significantly surpassing the thermal Dark Matter benchmark.

    hep-phastro-ph.COhep-exJHEP(2025)·5 citations
18. 18*

    T-odd observables from anomalous $tbW$ couplings in single-top W associated production at the LHC

    Saurabh D. Rindani🇮🇳

    We investigate the possibility that an imaginary anomalous $tbW$ coupling can be measured in the process $pp\to t{W}^{-}X$ by means of T-odd observables. One such observable is the polarization of the top quark transverse to the production plane. Another is the asymmetry between the cross sections with a positive and with a negative value of a certain T-odd correlation constructed out of observable momenta when the top quark decays leptonically. The mean value of this correlation, which is also T-odd, is the third observable. These three T-odd observables are shown to be proportional to the imaginary part of only one of the $tbW$ anomalous couplings, the other couplings giving vanishing contributions. This imaginary part could signal either a CP-odd coupling, or an absorptive part in the effective coupling. We estimate the 1-$\sigma$ limits that might be derived in the case of each of these observables for centre-of-mass energies 7, 8, 13 and 14 TeV at the LHC.

    hep-phProc.Indian Natl.Sci.Acad.(2026)·0 citations
19. 19*

    Multi-axion like description of the dark sector in light of the Hubble and ${\sigma }_8$ tensions

    John Dumancic🇺🇸 · Richard Gass🇺🇸 · Ennis Mawas🇺🇸 · L.C.R. Wijewardhana🇺🇸

    Local methods of direct determination of the Hubble constant and ${\sigma }_8$ seem to conflict with the predictions made from the cosmic microwave background and $\Lambda$CDM. We propose a proof-of-concept model that models portions of the dark sector as several coupled axion-like fields, resulting in both early and late time departures from $\Lambda$CDM. We determine that the model successfully eliminates both the Hubble and ${\sigma }_8$ tensions, while remaining consistent with both the DESI survey and the BAO sound horizon.

    ↳ astro-ph.COgr-qchep-phhep-th0 citations
20. 20*

    Three family supersymmetric Pati-Salam model from rigid intersecting D6-branes

    Adeel Mansha🇨🇳 · Mudassar Sabir🇨🇳 · Tianjun Li🇨🇳 · Luyang Wang🇨🇳

    We construct, for the first time, a three-family $\mathcal{N}=1$ supersymmetric Pati-Salam model from rigid intersecting D6-branes on a factorizable ${\mathbb{T}}^6/({\mathbb{Z}}_2\times {\mathbb{Z}}_2^{\prime })$ orientifold with discrete torsion. The factorizable geometry allows for explicit control over rigid cycles and moduli stabilization. We can break the Pati-Salam gauge symmetry down to the Standard Model (SM) gauge symmetry via the supersymmetry preserving Higgs mechanism, generate the SM fermion masses and mixings, and break the supersymmetry via gaugino condensations in the hidden sector.

    ↳ hep-thhep-phPRD(2025)·4 citations
21. 21*

    Lattice QCD calculation of the Compton amplitude subtraction function

    K. U. Can🇦🇺 · A. Hannaford-Gunn🇦🇺 · R. Horsley🇬🇧 · P. E. L. Rakow🇬🇧 · T. Schar🇦🇺 · G. Schierholz🇩🇪 · H. Stüben🇩🇪 · R. D. Young🇦🇺 · J. M. Zanotti🇦🇺

    The Compton amplitude subtraction function is an essential component in work concerning both the proton radius puzzle and the proton-neutron mass difference. However, owing to the difficulty in determining the subtraction function, it remains a key source of uncertainty in these two contexts. Here, we use the Feynman-Hellmann method to determine this subtraction function directly from lattice QCD. Furthermore, we demonstrate how to control dominant discretisation artefacts for this calculation, eliminating a major source of systematic error. This calculation is performed for a range of hard momentum scales, and three different sets of gauge configurations for pion masses about 400 MeV. Our results show good agreement with continuum OPE expectations. As such, this work paves the way for model-independent and precise determinations of the subtraction function over a wide range of kinematics.

    ↳ hep-lathep-phnucl-thPRD(2025)·5 citations
22. 22*

    Hybrid spin-dependent and hybrid-quarkonium mixing potentials at order $(1/m_Q{)}^1$ from SU(3) lattice gauge theory

    Carolin Schlosser🇩🇪 · Marc Wagner🇩🇪

    We present the first lattice gauge theory results for hybrid spin-dependent and hybrid-quarkonium mixing potentials appearing at order $(1/m_Q{)}^1$ in the Born-Oppenheimer Effective Field theory for hybrid mesons with gluon spin ${\kappa }^{PC}=1^{+-}$. Specifically, we compute the four unknown potentials $V_{11}^{sa}(r)$, $V_{10}^{sb}(r)$, which are relevant for the hyperfine splitting in heavy hybrid meson spectra, as well as $V_{{\Sigma }_u^{-}}^{\text{mix}}(r)$ and $V_{{\Pi }_u}^{\text{mix}}(r)$, which describe the mixing of heavy hybrid mesons with ordinary quarkonium. We relate these potentials to matrix elements, which we extract from generalized Wilson loops with a chromomagnetic field insertion along one of the temporal lines and suitable hybrid creation operators replacing the spatial lines. We use gradient flow, which facilitates the renormalization of the matrix elements and has the additional benefit of significantly reducing statistical noise. We present results for gauge group SU(3) and lattice spacing $a=0.060$ fm. Our results demonstrate that a future combined continuum and zero-flow time extrapolation is possible within our setup, which will be necessary to reliably predict the hyperfine splitting of heavy hybrid mesons as well as their mixing with ordinary quarkonium through coupled channel Schrödinger equations.

    ↳ hep-lathep-phPRD(2025)·9 citations
23. 23*

    Heavy Axions Can Disrupt $\gamma$-ray Bursts

    Oindrila Ghosh🇸🇪 · Sunniva Jacobsen🇸🇪 · Tim Linden🇸🇪

    Axion-like particles (ALPs) can be produced in the hot dense plasma of fireballs that develop in the initial stage of $\gamma$-ray burst (GRB) outflows. They can transport an enormous amount of energy away from the jet by propagating out of the fireball. The photons produced by the eventual decay of such ALPs do not reach a sufficient density to re-thermalize through pair production, preventing fireball re-emergence. Thus, the production of heavy ALPs disrupts the fireball and dims GRBs, allowing bright GRB observations to strongly constrain the existence of heavy ALPs. By adding ALP interactions to existing models of GRB fireballs, we set competitive bounds on the ALP-photon coupling down to $g_{a\gamma \gamma }\sim 4\times 10^{-12}{\mathrm{GeV}}^{-1}$ for ALPs in the mass range of 200 MeV - 5 GeV.

    ↳ astro-ph.HEastro-ph.COhep-phPRD(2026)·4 citations
24. 24*

    Remarks on brane-antibrane inflation

    Gonzalo Villa🇬🇧

    We provide an accessible review to the eta problem in brane-antibrane inflation and a recently proposed solution. The description of the antibrane by means of nonlinearly realized supersymmetry suggests a simple stabilization mechanism for the volume mode, based on the most general Kahler and superpotentials compatible with the symmetries of the problem. This work is a contribution to the proceedings of the second general meeting of the COST Action CA21106 (Cosmic WISPers) and is based on arXiv:2410.00097 .

    ↳ hep-thastro-ph.COhep-phPoS(2025)·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.