Thu·Oct 17, 2024Thursday·October 17, 2024

1. 01*

   Theoretical study on low-lying hidden-bottom and double-bottom tetraquark states

   Lin-Juan Jiang🇨🇳 · Chun-Sheng An🇨🇳 · Cheng-Rong Deng🇨🇳 · Gang Li🇨🇳 · Ju-Jun Xie🇨🇳

   We perform a theoretical study on the spectrum of the low-lying hidden-bottom ($q\bar{q}b\bar{b}$ with $q=$ $u$, $d$ and $s$) and double-bottom ($q\bar{q}bb$) tetraquark states within a nonrelativistic quark model, in which the instanton-induced interaction is taken as the residual spin-dependent hyperfine interaction between quarks. All the model parameters are fixed by fitting the spectrum of the ground hadron states. The numerical results indicate that masses of several $X_{q\bar{q}}$, $Z_b$, and $Z_{bs}$ tetraquark states are below and near thresholds of corresponding meson-meson channels, thus these states may form components of exotic meson states with reasonable probabilities. Especially, in present model, masses of several obtained states with quantum number $I^G(J^P)=1^{+}(1^{+})$ are close to $Z_b^{\pm }(10610)$, so one may expect these states to be non-negligible components of the experimentally observed $Z_b$ states. Concerning to the double-bottom tetraquark states, the present results are in general consistent with other previous works. Two possible stable $T_{bb}$ states with quark content $bb\bar{n}\bar{n}$ ($n=u$ or $d$ quark) lying at energies $10558$ MeV and $10650$ MeV are found, and one possible stable $bb\bar{n}\bar{s}$ state is found, whose energy is $\sim 10687$ MeV.

   hep-phEPJC(2024)·4 citations
2. 02*

   Testable leptogenesis and $0\nu \beta \beta$ decay in extended seesaw model

   Gang Li🇨🇳 · Michael J. Ramsey-Musolf🇨🇳 · Supriya Senapati🇺🇸 · Sebastián Urrutia Quiroga🇺🇸

   We investigate the possibility of observable neutrinoless double beta decay $(0\nu \beta \beta )$ and viable leptogenesis within a low-scale extended inverse seesaw mechanism with additional sterile neutrinos. General effective field theory (EFT) considerations suggest that if there are experimentally observable signatures in $0\nu \beta \beta$-decay and a lepton asymmetry generated by heavy right-handed neutrino decays, thermal leptogenesis is likely to be unviable. However, in this work, we show that in the context of low-scale leptogenesis, one can obtain the observed baryon asymmetry of the universe and observable signatures of $0\nu \beta \beta$ decay in the presence of additional sterile neutrinos. In this framework, the light neutrino masses are suppressed by the extended seesaw parameter, $\mu$, thereby allowing for $\mathcal{O}(10\mathrm{TeV})$ right-handed (RH) neutrinos, while avoiding small Yukawa couplings as in other neutrino mass models and near degeneracies in the RH neutrino spectrum as required by the low-scale leptogenesis paradigm. Contributions to the $0\nu \beta \beta$-decay rate from additional sterile neutrinos can be appreciable, while the corresponding contributions to the early universe lepton asymmetry washout rate are suppressed by other parameters not entering the $0\nu \beta \beta$-decay amplitudes. We show that for keV-MeV scale, sterile neutrinos future ton-scale $0\nu \beta \beta$-decay experiments offer potential signals while maintaining viable leptogenesis.

   hep-phnucl-th1 citation
3. 03*

   Pion condensation at rotation in magnetic field, electric and scalar potential wells

   D. N. Voskresensky🇷🇺

   Instability of the charged pion vacuum resulting in the pion condensation is studied within the $\lambda |\varphi {|}^4$ model at the rapid rotation of the system in presence of external fields. Case of the static external scalar and electric square potential wells and the uniform magnetic field is studied in detail. The Meissner and Aharonov-Bohm effects and the London moment are taken into account. Analogies and differences with the behavior of metallic superconductors under the action of the rotation and the external magnetic field are analysed.

   hep-phcond-mat.supr-connucl-thPRD(2025)·9 citations
4. 04*

   Approach to meson-baryon femtoscopy using effective field theories

   Álvaro Peña Almazán🇪🇸 · Juan M. Torres-Rincon🇪🇸

   We calculate several femtoscopy correlation functions in the strangeness sectors $S=0$ and $S=-2$ for meson-baryon interactions. We combine the amplitudes of chiral perturbation theory at leading order with the TROY (T-matrix-based Routine for HadrOn femtoscopY) framework. We consider the correlation function for the ${\pi }^{+}$p and ${\pi }^{-}$p channels, which are currently under analysis by the ALICE collaboration at the LHC. Furthermore, we will show that analogous interactions can be used to reproduce the results for $K_S\Lambda$ correlation functions obtained by ALICE collaboration in PbPb collisions.

   hep-phnucl-exnucl-thPoS(2025)·0 citations
5. 05*

   Light new physics in the top quark sample from the Large Hadron Collider

   Dibyashree Sengupta🇮🇹

   Contrary to the general trend of looking for new physics at energies beyond the current reach of the Large Hadron Collider (LHC), this article proposes a strategy to look for light new physics via a meticulous study of well known and well-measured kinematic distributions. In this article, we propose performing such a study in the top-quark sample since the LHC, being a top-quark factory, helps in precise measurement of several observables related to the properties of the top-quark. One such observable is the invariant mass $m_{b\ell }$ of the b-jet and the charged lepton obtained from fully leptonic decay of pair-produced $t\bar{t}$ events. Such a strategy can be employed to extract hints for any Beyond Standard Model (BSM) scenario that allow for an exotic particle with mass close to the mass of top-quark ($m_t$) and can yield the same final state as fully leptonic decay of pair-produced top quarks. To provide a concrete study, we analyze a supersymmetric scenario with light right-handed stop quark with mass $\approx m_t$. The particle spectrum is such that the mass differences between the particles involved in the signal are small enough to lie in a potential blindspot and may be not yet firmly excluded by current LHC searches. Such spectra can yield a deviation from the Standard Model prediction in the lower region of the $m_{b\ell }$ distribution. This feature can be observed in any BSM framework that harbours light new physics that have so far escaped the LHC searches and hence can be used to extract light new physics signal irrespective of the underlying theory.

   hep-phPoS(2025)·1 citation
6. 06*

   Natural anomaly-mediation from the landscape with implications for LHC SUSY searches

   Dibyashree Sengupta🇮🇹

   Supersymmetric models with the anomaly-mediated SUSY breaking (AMSB) have run into serious conflicts with 1. LHC \textit{sparticle} and Higgs mass constraints, 2. constraints from wino-like WIMP dark matter searches and 3. bounds from naturalness. These conflicts may be avoided by introducing changes to the underlying phenomenological models providing a setting for natural anomaly-mediation (nAMSB). We examine spectra of nAMSB arising from string landscape. Here, we investigated LHC constraints on nAMSB models that allow $m_{3/2}$ to lie within 90$-$200 TeV which may soon be discovered or falsified by a combination of 1. soft OS dilepton plus jet+ MET (OSDLJMET) searches which arise from higgsino pair production, 2. non-boosted hadronically decaying wino pair production searches and 3. same-sign diboson + MET searches arising from wino pair production followed by wino decay to W +higgsino. Some excess above SM background in the OSDLJMET channel already seems to be present in both ATLAS and CMS data.

   hep-phPoS(2025)·0 citations
7. 07*

   Revisiting the proton-antiproton scattering using a constituent-quark-model based coupled-channels calculation

   P. G. Ortega🇪🇸 · D. R. Entem🇪🇸 · F. Fernandez🇪🇸 · J. Segovia🇪🇸

   Motivated by the last experimental and theoretical advances in the analysis of possible baryonium resonances, the $X(1835)$ and their partners, we perform a constituent-quark-model based coupled-channels calculation of the proton-antiproton scattering in order to analyze the possible existence of bound states or near-threshold structures. The used $N\overline{N}$ potential is derived from a $G$-parity transformation of the quark-model-based $NN$ interaction which has described well deuteron properties, $NN$ phase shifts, and even hadron-hadron phenomenology. The additional $N\overline{N}$ annihilation is taken into account by a complex phenomenological potential whose real part is generated by one-pion and one-gluon exchange annihilation potentials and its imaginary part is an energy-independent potential of Gaussian form. Then, all the parameters of the interaction are constrained by the $NN$ sector except those determining the imaginary part of the annihilation potential. Our study concludes that the nucleon-antinucleon dynamics is complex and rich in scattering singularities near the proton-antiproton and neutron-antineutron thresholds.

   hep-phhep-exhep-latnucl-ex+1PLB(2025)·7 citations
8. 08*

   Potential of constraining the Fifth Force Using the Earth as a Spin and Mass Source from space

   Zheng-Ting Lai🇨🇳 · Jun-Xu Lu🇨🇳 · Li-Sheng Geng🇨🇳 · Kai Wei🇨🇳 · Wei Ji🇩🇪

   We explore the potential of conducting an experiment in a low Earth orbit spacecraft and using the Earth as a spin and mass source to constrain beyond-the-standard-model (BSM) long-range spin- and velocity-dependent interactions, which are mediated by the exchange of an ultralight $\left(m_{Z^{\prime }}<10^{-10}\text{eV}\right)$ or massless intermediate vector boson. The high speed of the low Earth orbit spacecraft can enhance the sensitivity to velocity-dependent interactions. The periodicity enables efficient extraction of signals from background noise, thereby improving the experiment's accuracy. Combining these advantages, we demonstrate theoretically that the novel Spacecraft-Earth model can improve existing bounds on these exotic interactions by up to three orders of magnitude, using the China Space Station (CSS) as a representative low-Earth-orbit carrier. Such a model, if successfully implemented, may provide an innovative strategy for detecting ultralight dark matter and yield tighter constraints on certain coupling constants of exotic interactions.

   hep-phhep-exhep-thnucl-thChin.Phys.Lett.(2026)·5 citations
9. 09*

   Cosmological Roles of Dark Photons in Axion-induced Electroweak Baryogenesis

   Kwang Sik Jeong🇰🇷 · Ju Hyeong Kang🇰🇷 · Shota Nakagawa🇨🇳

   By coupling to both the Higgs and electroweak gauge sectors, an axion can generate the matter-antimatter asymmetry in the universe via electroweak baryogenesis when the axion decay constant lies within the range of approximately $10^5$ and $10^7$GeV, corresponding to axion masses between the MeV and GeV scales. In this work, we explore the intriguing possibility that the axion interacts with a dark sector, particularly with dark photons through anomalous couplings. Notably, axion-coupled dark photons can play multiple roles, including $(i)$ suppressing the branching ratio of axion decay to Standard Model (SM) particles, which would otherwise conflict with the constraints from supernovae explosions, Big Bang nucleosynthesis, and neutron star merger events, $(ii)$ serving as a candidate for cold dark matter if they are massive and stable, and $(iii)$ contributing to dark radiation if they are ultralight. The axion decouples from the SM thermal bath when it becomes non-relativistic, facilitating the production of dark matter dark photons through the freeze-in mechanism, while dark radiation dark photons are thermally generated prior to the electroweak phase transition.

   hep-phastro-ph.COJCAP(2025)·6 citations
10. 10*

    Féeton ($B-L$ Gauge Boson) Dark Matter Testable in Future Direct Detection Experiments

    Yu Cheng🇰🇷 · Jie Sheng🇨🇳 · Tsutomu T. Yanagida🇯🇵

    In this paper, we revisit the féeton (gauge boson of $U(1{)}_{B-L}$ symmetry) dark matter scenario, and first point out the $U(1)$ gauge symmetry can be a linear combination of the $B-L$ and the SM hypercharge gauge symmetries. With the redefinition of $B-L$ charge of fermions, the coupling between electron and féeton can be enhanced. After showing the parameter space required from the DM stability and cosmic production, we discuss the potential for verifying them in dark matter direct detection experiments. The results show that future experiments, such as SuperCDMS, have a sensitivity to reach the féeton DM region consistent with its cosmic production.

    hep-phJHEP(2024)·2 citations
11. 11*

    $t\bar{t}t\bar{t}$: NLO QCD corrections in production and decays for the $4\ell$ channel

    Nikolaos Dimitrakopoulos🇩🇪

    We briefly summarise the results for the four top-quark production process in the 4$\ell$ decay channel at NLO accuracy in perturbative QCD. We employ the narrow-width approximation for the treatment of the unstable particles, preserving spin correlations to NLO accuracy throughout our computations. The NLO QCD corrections are applied to both the production and decays of the four tops. We investigate the overall size of the NLO QCD corrections and the impact of neglecting higher-order effects in top-quark decays.

    hep-phPoS(2025)·0 citations
12. 12*

    Exploring Quantum Aspects of Dark Matter Axions and Dark Photons Transitioning to Photons in a Resonant Cavity

    Ruifeng Zheng🇨🇳 · Puxian Wei🇨🇳 · Qiaoli Yang🇨🇳

    When axion cold dark matter interacts with a static magnetic field, it can be converted to photons with energy near the axion's mass. Classical analysis shows that incorporating a resonant cavity significantly enhances this conversion rate, forming the basis for many experiments aimed at detecting dark matter axions. However, one might ask: Does the axion-photon conversion rate increase for a single axion-photon transition? Answering this question could lead to optimizing the search for axions by integrating quantum measurement techniques. In this paper, we demonstrate that at the quantum level, single axion-photon transitions are amplified by the cavity quality factor $Q$. Furthermore, the coherence of dark matter waves is unnecessary during the measurement. The underlying principle is similar to the Purcell effect. Additionally, we provide an analysis of the scenario involving dark photon dark matter.

    hep-phquant-ph3 citations
13. 13*

    Probing $\tau$ lepton dipole moments at future Muon Colliders

    ZeQiang Wang🇧🇪

    The anomalous magnetic moments of leptons represent excellent probes of the Standard Model and therefore also of possible new physics effects. In particular, the persisting hint of new physics in the muon $g$-2 motivates the investigation of similar effects also in the other leptonic dipoles. In this work, we examine the new physics sensitivity of the tau $g$-2 at future high-energy Muon Collider. We show that these facilities can access a number of processes like the Drell-Yan processes ${\mu }^{+}{\mu }^{-}\to {\tau }^{+}{\tau }^{-}(h)$, or vector-boson-fusion processes such as ${\mu }^{+}{\mu }^{-}\to {\mu }^{+}{\mu }^{-}{\tau }^{+}{\tau }^{-}$ and ${\mu }^{+}{\mu }^{-}\to {\nu }_{\mu }{\bar{\nu }}_{\mu }{\tau }^{+}{\tau }^{-}$ those can probe the tau $g$-2 at the level of $\mathcal{O}(10^{-5}-10^{-4})$, a resolution that is orders of magnitude better than the current bounds.

    hep-phPoS(2025)·6 citations
14. 14*

    Polarization options in inclusive DIS off tensor polarized deuteron

    Wim Cosyn🇺🇸 · Brandon Roldan Tomei🇺🇸 · Alan Sosa🇺🇸 · Allison Zec🇬🇧

    In the near future, the Jefferson Lab $b_1$ experiment will provide the second measurement of tensor polarized asymmetries in inclusive DIS on the deuteron. In this asymmetry, 4 independent tensor polarized structure functions contribute. This necessitates systematic approximations in the extraction of the leading twist structure function $b_1$ from a single tensor asymmetry measurement. Contamination from higher twist structure functions and kinematic effects is discussed here. Using a deuteron convolution model, we quantify the systematic errors from these approximations for two different choices for the target polarization direction (momentum transfer, electron beam direction). For Jefferson Lab 12 GeV kinematics, the systematic error turns out to be comparable between the two polarization options, while at higher $Q^2$ values the momentum transfer direction is preferred.

    hep-phnucl-exnucl-thEPJA(2025)·4 citations
15. 15*

    A dispersive estimate of the $a_0(980)$ contribution to $(g-2{)}_{\mu }$

    Oleksandra Deineka🇩🇪 · Igor Danilkin🇩🇪 · Marc Vanderhaeghen🇩🇪

    A dispersive implementation of the $a_0(980)$ resonance to $(g-2{)}_{\mu }$ requires the knowledge of the double-virtual $S$-wave ${\gamma }^{\ast }{\gamma }^{\ast }\to \pi \eta /KK(I=1)$ amplitudes. To obtain these amplitudes, we used a modified coupled-channel Muskhelishvili-Omnes formalism, with input from the left-hand cuts and the hadronic Omnes matrix. The latter was derived using a data-driven N/D method, where the hadronic left-hand cuts were approximated via a conformal expansion. Due to the absence of direct hadronic data in the $\pi \eta$ channel, the expansion coefficients were fitted to various experimental data sets on two-photon fusion processes with $\pi \eta$ and $KK$ final states. The resulting dispersive estimate for the $a_0(980)$ contribution to $(g-2{)}_{\mu }$ is $a_{\mu }^{HLbL}[a_0(980){]}_{resc.}=-0.43(1)(2)\times 10^{-11}$, which presents an order of magnitude improvement in precision over the narrow resonance approximation.

    hep-phPRD(2025)·47 citations
16. 16*

    Leptophilic $Z^{\prime }$ bosons at the FCC-ee: discovery opportunities

    Rebeca Gonzalez Suarez🇸🇪 · Baibhab Pattnaik🇪🇸 · José Zurita🇪🇸

    We examine the possibility to detect new SM-neutral vector bosons ($Z^{\prime }$) that couple exclusively to leptons in the electron-positron mode of the Future Circular Collider (FCC-ee). Focusing on the $Z^{\prime }$ production with a radiated photon search channel, we show that the FCC-ee can significantly extend the unprobed parameter space by increasing the exclusion in the coupling by one to two orders of magnitude in the kinematically allowed mass range (from 10 GeV to 365 GeV), with the leading sensitivity being driven by the muon channel. In doing so, it outperforms other proposed lepton collider options such as CLIC and ILC in this range of masses. Further, we discuss the possibility of improving the sensitivity of the FCC-ee to this model through the modification of the dilepton invariant mass resolution and the photon energy resolution. The impact of systematic uncertainties on the expected sensitivities is also studied.

    hep-phPRD(2025)·10 citations
17. 17*

    Generalised Antenna Functions for Higher-Order Calculations

    Elliot Fox🇬🇧 · Nigel Glover🇬🇧 · Matteo Marcoli🇬🇧

    In this paper we discuss the definition, the construction and the implementation of \textit{generalised antenna functions} for final-state radiation up to Next-to-Next-to-Leading Order (NNLO) in QCD. Generalised antenna functions encapsulate the singular behaviour of unresolved emissions when these occur within multiple hard radiators and not just two of them, as for traditional antenna functions. The construction of such objects is possible thanks to the recently proposed algorithm for building \textit{idealised antenna functions} from a target set of infrared limits. Generalised antenna functions bring major simplifications in the assemblage of subtraction terms in the context of the antenna scheme at NNLO and beyond, as well as a substantial computational speedup of higher-order calculations. We discuss in detail the improvements on the formal and practical side for the computation of the NNLO correction to three-jet production at electron-positron colliders, providing a thorough numerical validation of the newly proposed scheme. For this calculation one can expect almost an order of magnitude speedup with respect to the original implementation.

    hep-phJHEP(2024)·18 citations
18. 18*

    Effects of threshold resummation for large-$x$ PDF in large momentum effective theory

    Xiangdong Ji🇺🇸 · Yizhuang Liu🇵🇱 · Yushan Su🇺🇸 · Rui Zhang🇺🇸

    Parton distribution functions (PDFs) at large $x$ are challenging to extract from experimental data, yet they are essential for understanding hadron structure and searching for new physics beyond the Standard Model. Within the framework of the large momentum $P^z$ expansion of lattice quasi-PDFs, we investigate large $x$ PDFs, where the matching coefficient is factorized into the hard kernel, related to the active quark momentum $x{P}^z$, and the threshold soft function, associated with the spectator momentum $(1-x)P^z$. The renormalization group equation of the soft function enables the resummation of the threshold double logarithms ${\alpha }^k{\ln }^{2k}(1-x)$, which is crucial for a reliable and controllable calculation of large $x$ PDFs. Our analysis with pion valence PDFs indicates that perturbative matching breaks down when the spectator momentum $(1-x)P^z$ approaches ${\Lambda }_{\mathrm{QCD}}$, but remains valid when both $x{P}^z$ and $(1-x)P^z$ are much larger than ${\Lambda }_{\mathrm{QCD}}$. Additionally, we incorporate leading renormalon resummation within the threshold framework, demonstrating good perturbative convergence in the region where both spectator and active quark momenta are perturbative scales.

    hep-phhep-latnucl-thJHEP(2025)·21 citations
19. 19*

    Mass Prediction of the Weak and Higgs Bosons Using the Massless Spin-Exchange Preons Model: An Alternative to the Higgs Mechanism in Yang-Mills Theory

    Jau Tang🇨🇳 · Qiang Tang🇨🇳

    We modify the Yang-Mills model using massless preon pairs to describe the photon isospin singlet and the Z and W bosons. Unlike the Higgs mechanism, which depends on a scalar field, our model employs Gell-Mann generators, revealing that the masses of W and Z bosons arise from the internal dynamics of chiral preon pairs. With no adjustable parameters, we predict 0.87 (experimental value: 0.88), a Weinberg angle of 30{\deg} (vs. 29{\deg}), and a decay width ratio of 0.87 (vs. 0.84). Additionally, we find (vs. 1.56) for the Higgs boson. Our approach introduces a curl operator leading to chirality, characterized by a topological structure of Möbius tori, providing new insights into particle interactions and challenging existing theoretical paradigms.

    hep-phhep-th0 citations
20. 20*

    Application of Machine Learning Based Top Quark and W Jet Tagging to Hadronic Four-Top Final States Induced by SM and BSM Processes

    Jiří Kvita🇨🇿 · Petr Baroň🇨🇿 · Monika Machalová🇨🇿 · Radek Přívara🇨🇿 · Rostislav Vodák🇨🇿 · Jan Tomeček🇨🇿

    We apply both cut-based and machine learning techniques using the same inputs to the challenge of hadronic jet substructure recognition, utilizing classical subjettiness variables within the Delphes parameterized detector simulation framework. We focus on jets generated in simulated proton-proton collisions, identifying those consistent with the decay signatures of top quarks or W bosons. Such jets are employed in four-top quark events in fully hadronic final states stemming from both the Standard Model as well as from a new physics process of a hypothetical scalar resonance y0 decaying into a pair of top quarks. We reconstruct the resonance invariant mass and compare it properties over the falling background using the two tagging approaches, with implications to LHC searches.

    hep-phhep-exMod.Phys.Lett.A(2026)·1 citation
21. 21*

    Dark Matter Interactions in White Dwarfs: A Multi-Energy Approach to Capture Mechanisms

    Jaime Hoefken Zink🇮🇹 · Shihwen Hor🇯🇵 · Maura E. Ramirez-Quezada🇩🇪

    White dwarfs offer a compelling avenue for probing interactions of dark matter particles, particularly in the challenging sub-GeV mass regime. The constraints derived from these celestial objects strongly depend on the existence of high dark matter densities in the corresponding regions of the Universe, where white dwarfs are observed. This implies that excluding the parameter space using local white dwarfs would present a significant challenge, primarily due to the low dark matter density in the solar neighbourhood. This limitation prompts the exploration of alternative scenarios involving dark matter particles with a diverse spectrum of kinetic energies. In this work, we investigate how these dark matter particles traverse the star, interact with stellar matter, and ultimately get captured. To accomplish this, we approximate the dark matter flux as a delta function and inspired on the Three Portal Model, we assume that fermionic dark matter interacts with stellar matter either through a broken $U(1)$ gauge vector mediator or a scalar. In our computations, we consider how interactions might vary across different energy regimes, from high-energy deep inelastic scattering and inelastic scatterings via the production of $N-$ and $\Delta -$ resonances to lower-energy elastic interactions with nucleons and nuclei. Our study models these inelastic resonant interactions with dark matter and vector or scalar mediators for the very first time. We provide insights into the specific conditions required for successfully boosted dark matter capture in white dwarfs. We found that, in general, dark matter capture is most likely to occur at low energies, as expected. However, in the high-energy regime, there remains a small window for capture through resonant and deep inelastic scattering processes.

    hep-phastro-ph.HEJHEP(2025)·7 citations
22. 22*

    Generalized Uncertainty Principle and the Zeeman Effect: Relativistic Corrections Unveiled

    Gaurav Bhandari🇵🇰 · S. D. Pathak🇵🇰 · Manabendra Sharma🇹🇭

    In this paper, we calculate the relativistic corrections to the Zeeman effect for hydrogen-like atoms based on the Generalized Uncertainty Principle (GUP). We propose a relativistic GUP algebra using the Stetsko and Tkachuk approximation and incorporate these corrections into the Zeeman effect. In the relativistic limit, our results recover previously derived GUP corrections as well as the standard Lande energy shift expression when GUP effects are absent. This work presents a generalized expression that accounts for both relativistic and GUP corrections to the Zeeman effect.

    ↳ quant-phhep-phhep-thNPB(2025)·10 citations
23. 23*

    Renormalization group approaches to Quantum Gravity and Tensions in Modern Cosmology

    Vasilios Zarikas🇬🇷

    Asymptotic Safety is a promising framework towards the understanding, in a non-perturbative way, of Quantum Gravity. It treats the Newton's constant G_N and the cosmological constant \Lambda as running coupling of an effective action. At the phenomenological point of view the values of G_N and \Lambda depend on the energy density of the system under consideration. This fact has interesting astrophysical and cosmological consequences. The present work discusses the effects on the distance measurements from SNIa light curves and on the strong and weak gravitational lensing measurements.

    ↳ astro-ph.COgr-qchep-phhep-thPoS(2024)·4 citations
24. 24*

    Soft Metric Fluctuations During Inflation

    Daniel Green🇺🇸 · Kshitij Gupta🇺🇸

    The conservation of the long wavelength fluctuations of the metric plays a vital role in cosmology as the link between quantum fluctuations during inflation and late time observations. This is a well-known property of the classical evolution equations, but demonstrating that it is robust to quantum correction involves a number of technical arguments. In this paper, we will use effective field theory (EFT) techniques to demonstrate the all orders conservation of the super-horizon scalar and tensor fluctuations of the metric during inflation. We show how to construct an EFT for these soft modes, in analogy with Soft de Sitter Effective Theory. We pay particular attention to how the breaking of time-diffeomorphisms by the inflationary background introduces new time scales that alter the structure of the EFT. In this description, the all orders conservation of the metric fluctuations is a direct consequence of symmetries and power counting that cannot be altered by loop corrections. We further show that this holds when the inflaton (or metric fluctuations) is coupled to additional heavy fields, as in quasi-single field inflation. We match this behavior to several calculations in the ultraviolet (UV) theory and show how the Mellin representation enables a more transparent connection between the UV and the EFT descriptions.

    ↳ hep-thastro-ph.COgr-qchep-phPRD(2025)·17 citations
25. 25*

    Multiplicities of positive and negative pions, kaons and unidentified hadrons from deep-inelastic scattering of muons off a liquid hydrogen target

    G. D. Alexeev · M. G. Alexeev🇮🇹 · C. Alice🇮🇹 · A. Amoroso🇮🇹 · V. Andrieux🇺🇸 · V. Anosov · K. Augsten🇨🇿 · W. Augustyniak🇵🇱 · C. D. R. Azevedo🇵🇹 · B. Badelek🇵🇱 · J. Barth🇩🇪 · R. Beck🇩🇪 and 158 other authors

    The multiplicities of positive and negative pions, kaons and unidentified hadrons produced in deep-inelastic scattering are measured in bins of the Bjorken scaling variable $x$, the relative virtual-photon energy $y$ and the fraction of the virtual-photon energy transferred to the final-state hadron $z$. Data were obtained by the COMPASS Collaboration using a 160 GeV muon beam of both electric charges and a liquid hydrogen target. These measurements cover the kinematic domain with photon virtuality $Q^2>1$ (GeV/$c{)}^2$, $0.004<x<0.4$, $0.1<y<0.7$ and $0.2<z<0.85$, in accordance with the kinematic domain used in earlier published COMPASS multiplicity measurements with an isoscalar target. The calculation of radiative corrections was improved by using the Monte Carlo generator DJANGOH, which results in up to 12\% larger corrections in the low-$x$ region.

    ↳ hep-exhep-phPRD(2025)·6 citations
26. 26*

    Exact relations between running of ${\alpha }_s$ and $\alpha$ in $\mathcal{N}=1$ SQCD+SQED

    A.L.Kataev🇷🇺 · K.V.Stepanyantz🇷🇺

    In $\mathcal{N}=1$ supersymmetric QCD-like theories we derive the (all-order) exact equations relating the renormalization group behaviour of the strong and electromagnetic couplings and prove that they are valid in the HD+MSL renormalization prescription. In particular, the $\beta$-function of $\mathcal{N}=1$ SQCD can be expressed in terms of the Adler $D$-function. If all favors have the same absolute value of the electromagnetic charges, it is also possible to write a simple relation between the $\beta$-functions for the strong and electromagnetic coupling constants. In this particular case there is a special renormalization group invariant relation.

    ↳ hep-thhep-lathep-phJETP Lett.(2025)·5 citations
27. 27*

    Efficient generation of divergent and collimated hot electrons via a novel multi-beam two-plasmon decay and stimulated Raman scattering mechanism

    K.Y. Meng · Z.H. Cai · J. Li🇨🇳 · C. Yao · L. Hao🇨🇳 · F.X. Zhou · R. Yan · J. Zheng🇨🇳

    In inertial confinement fusion (ICF) implosions, the preheating risks associated with hot electrons generated by laser plasma instabilities (LPI) are contingent upon the angular characteristics of these hot electrons for a given total energy. Using particle-in-cell simulations, we reveal a novel multi-beam collaborative mechanism of two-plasmon decay (TPD) and stimulated Raman scattering (SRS), and investigate the angular variations of hot electrons generated from this shared TPD-SRS (STS) instability driven collectively by dual laser beams with varying incident angles ${\theta }_{in}$ ($24^{\circ }$ to $55^{\circ }$ at the incident plane) for typical ICF conditions. In the simulations with ${\theta }_{in}\gtrsim 44^{\circ }$, STS emerges as the dominant mechanism responsible for hot electron generation, leading to a wide angular distribution of hot electrons that exhibit both pronounced divergent and collimated components. The common Langmuir wave associated with STS plays a crucial role in accelerating both components.By properly modeling the STS common wave gains, we establish scaling relations between these gains and the energies of collimated and divergent hot electrons. These relations reveal that the divergent hot electrons are more sensitive to variations in gain compared to the collimated electrons. Additionally, the calculated gains qualitatively predict the asymmetry in hot electron angular distributions when the density gradients deviate from the bisector of the laser beams. Our findings offers insights for hot electron generation with multiple beams, potentially complementing previous experiments that underscore the critical role of overlapped intensity from symmetric beams within the same cone and the dominance of dual-beam coupling.

    ↳ physics.plasm-phhep-ph0 citations
28. 28*

    Computing real-time quantum path integrals on Sewed, almost-Lefschetz thimbles

    Zong-Gang Mou🇬🇧 · Paul M. Saffin🇬🇧 · Anders Tranberg🇳🇴

    We present a method to compute real-time path integrals numerically, by Monte-Carlo sampling on near-Lefschetz thimbles. We present a collection of tools based on the Lefschetz thimble methods, which together provide an alternative to existing methods such as the Generalised thimble. These involve a convenient coordinate parameterization of the thimble, direct numerical integration along a radial coordinate into an effective path integral weight and locally deforming the Lefschetz thimble using its Gaussian (non-interacting theory) counterpart in a region about the critical point. We apply this to quantum mechanics, identify possible pitfalls and benefits, and benchmark its efficiency.

    ↳ hep-lathep-phhep-thJHEP(2025)·1 citation
29. 29*

    More Nonlinearities? Electromagnetic and Gravitational Mode Mixing in NSBH Mergers

    Fawzi Aly🇺🇸 · Mahmoud A. Mansour🇯🇵 · Dejan Stojkovic🇺🇸

    We investigate the possibility of electromagnetic fields leaving imprints on gravitational wave (GW) signals from Neutron Star-Black hole (NSBH) mergers, specifically in the context of extreme mass ratio inspirals (EMRIs). Using black hole perturbation theory (BHPT) in the context of a minimally coupled Einstein-Maxwell system, we demonstrate that electromagnetic quasi normal modes(QNMs) can excite gravitational QNMs with frequencies that are linear or quadratic in the electromagnetic QNMs, at first level of mixing. Moreover, We then study the electromagnetism-gravity coupling by approximating the Regge-Wheeler and Zerilli potentials with Dirac delta functions. In this example, we examine gravitational perturbations induced by the electromagnetic field of an ideal dipole radially free fall towards the blackhole, building on calculations from a companion paper [1]. Our results show that both linear and quadratic electromagnetic QNMs appear in gravitational perturbations. In addition, linear gravitational QNMs are also excited due to the electromagnetic source, with their amplitudes depending on the details of the electromagnetic and gravitational potentials, analogous to gravitational mode mixing analysis. Furthermore, at late stages, gravitational perturbations might exhibit polynomial tails induced by electromagnetic perturbations. This article sets the stage for future numerical investigations aimed at identifying such modes in various scenarios.

    ↳ gr-qchep-phhep-thmath-ph+1PRD(2025)·4 citations
30. 30*

    An upper limit to the lifetime of stellar remnants from gravitational pair production

    Heino Falcke🇳🇱 · Michael F. Wondrak🇳🇱 · Walter D. van Suijlekom🇳🇱

    Black holes are assumed to decay via Hawking radiation. Recently we found evidence that spacetime curvature alone without the need for an event horizon leads to black hole evaporation. Here we investigate the evaporation rate and decay time of a non-rotating star of constant density due to spacetime curvature-induced pair production and apply this to compact stellar remnants such as neutron stars and white dwarfs. We calculate the creation of virtual pairs of massless scalar particles in spherically symmetric asymptotically flat curved spacetimes. This calculation is based on covariant perturbation theory with the quantum field representing, e.g.,\ gravitons or photons. We find that in this picture the evaporation timescale, $\tau$, of massive objects scales with the average mass density, $\rho$, as $\tau \propto {\rho }^{-3/2}$. The maximum age of neutron stars, $\tau \sim 10^{68}\text{yr}$, is comparable to that of low-mass stellar black holes. White dwarfs, supermassive black holes, and dark matter supercluster halos evaporate on longer, but also finite timescales. Neutron stars and white dwarfs decay similarly to black holes, ending in an explosive event when they become unstable. This sets a general upper limit for the lifetime of matter in the universe, which in general is much longer than the Hubble--Lemaître time, although primordial objects with densities above ${\rho }_{\text{max}}\approx 3\times 10^{53}\text{g/}{\text{cm}}^3$ should have dissolved by now. As a consequence, fossil stellar remnants from a previous universe could be present in our current universe only if the recurrence time of star forming universes is smaller than about $\sim 10^{68}\text{years}$.

    ↳ gr-qcastro-ph.HEhep-phhep-thJCAP(2025)·2 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.