Thu·Feb 22, 2024Thursday·February 22, 2024

1. 01*

   Revisiting formation of primordial black holes in a supercooled first-order phase transition

   Marcos M. Flores🇫🇷 · Alexander Kusenko🇯🇵 · Misao Sasaki🇯🇵

   We reexamine production of primordial black holes in a supercooled phase transition. While a mere overdensity associated with a surviving false-vacuum patch does not imply formation of a black hole, it is possible for such a patch to evolve and create a black hole, thanks to the gradient energy stored in the bubble wall.

   hep-phastro-ph.COPRD(2024)·65 citations
2. 02*

   Pion-nucleus elastic scatterings incorporating medium effects within the Eikonal-Glauber mode

   Hyeon-dong Han🇰🇷 · Parada T. P. Hutauruk🇰🇷 · Seung-il Nam🇰🇷

   In this present investigation, we explore the elastic scattering of pions with nuclei ($\pi$-$A$), primarily influenced by the $\Delta$(1232) resonance, within the Eikonal-Glauber model. The medium effects are incorporated by considering nuclear-density (${\rho }_A$) dependent masses of baryons and strong coupling constants. These dependencies are computed and parameterized up to $\mathcal{O}({\rho }_A^2)$ based on the quark-meson coupling (QMC) model. The Wood-Saxon type density profile is utilized for the bound nucleons within finite nuclei. The element ${\pi }^{+}$-$N$ scattering cross section for the Glauber approach is determined using the conventional effective Lagrangian method. Subsequently, we analyze the total cross sections for elastic scattering with ${}^4$He and ${}^{12}$C targets. Our numerical results demonstrate a favorable agreement with JINR data for the ${}^4$He target, accurately reproducing the total cross-section. However, when considering the ${}^{12}$C target, deviations of approximately $\lesssim 10\%$. We also consider the multiple-scattering effects inside the nucleus approximately, using the single-channel meson-baryon Bethe-Salpeter equation, resulting in the effective width broadening of the $\Delta$ resonance to reproduce the data better.

   hep-phnucl-thJ.Korean Phys.Soc.(2024)·1 citation
3. 03*

   Warm inflation with a heavy QCD axion

   Kim V. Berghaus🇺🇸 · Matthew Forslund🇺🇸 · Mark Vincent Guevarra🇺🇸

   We propose the first model of warm inflation in which the particle production emerges directly from coupling the inflaton to Standard Model particles. Warm inflation, an early epoch of sustained accelerated expansion at finite temperature, is a compelling alternative to cold inflation, with distinct predictions for inflationary observables such as the amplitude of fluctuations, the spectral tilt, the tensor-to-scalar ratio, and non-gaussianities. In our model a heavy QCD axion acts as the warm inflaton whose coupling to Standard Model gluons sources the thermal bath during warm inflation. Axion-like couplings to non-Abelian gauge bosons have been considered before as a successful microphysical theory with emerging thermal friction that can maintain finite temperature during inflation via sphaleron heating. However, the presence of light fermions charged under the non-Abelian group suppresses particle production, hindering a realization of warm inflation by coupling to QCD. We point out that the Standard Model quarks can be heavy during warm inflation if the Higgs field resides in a high-energy second minimum which restores efficient sphaleron heating. A subsequent large reheating temperature is required to allow the Higgs field to relax to its electroweak minimum. Exploring a scenario in which hybrid warm inflation provides the large reheating temperature, we show that future collider and beam dump experiments have discovery potential for a heavy QCD axion taking the role of the warm inflaton.

   hep-phastro-ph.COJCAP(2024)·19 citations
4. 04*

   Global quark spin correlations in relativistic heavy ion collisions

   Ji-peng Lv🇨🇳 · Zi-han Yu🇨🇳 · Zuo-tang Liang🇨🇳 · Qun Wang🇨🇳 · Xin-Nian Wang🇺🇸

   The observation of the vector meson's global spin alignment by the STAR Collaboration reveals that strong spin correlations may exist for quarks and antiquarks in relativistic heavy-ion collisions in the normal direction of the reaction plane. We propose a systematic method to describe such correlations in the quark matter. The correlations can be classified as local and long range types. We show in particular that the effective quark spin correlations contain the genuine spin correlations originated directly from the dynamical process as well as those induced by averaging over other degrees of freedom. We also show that such correlations can be studied by measuring the vector meson's spin density matrix and hyperon-hyperon and hyperon-anti-hyperon spin correlations. We present the relationships between these measurable quantities and spin correlations of quarks and antiquarks.

   hep-phPRD(2024)·43 citations
5. 05*

   Radiative Quarkonium decays into an Invisible ALP

   Luca Di Luzio🇮🇹 · Alfredo Walter Mario Guerrera🇮🇹 · Xavier Ponce Díaz🇮🇹 · Stefano Rigolin🇮🇹

   In this talk the ALP production from radiative quarkonium decays is presented. To this purpose, the relevant cross-section is computed from a $d=5$ effective Lagrangian containing simultaneous ALP couplings to $b(c)$-quarks and photons. The interplay between resonant and non-resonant contributions is shown to be relevant for experiments operating at $\sqrt{s}=m_{{\rm Y}(nS)}$, with $n=1,2,3$, while the non-resonant contribution dominates at the ${\rm Y}(4S)$ resonance. These effects imply that the experimental searches performed at with different experimental setups are sensitive to complementary combinations of ALP couplings. To illustrate these results, constraints from existing BaBar, Belle and Belle II data on ALPs decaying into invisible final states are derived. Finally, constrains from the recent BESIII measurements of the $J/\Psi \to \gamma a$ decay rate are also included for comparison.

   hep-ph0 citations
6. 06*

   Estimating the dark matter halo velocity and surface temperature of some known pulsars due to dark matter capture

   Debashree Sen🇰🇷 · Atanu Guha🇰🇷

   Considering four known pulsars J1906+0746, J1933-6211, J2043+1711 and the Vela pulsar, we study the scenario of dark matter (DM) capture in neutron stars (NSs). For the purpose we choose four well-known relativistic mean field models to obtain the radius corresponding to the observed mass of these pulsars and consequently the scattering cross-section of DM with the different particles of the $\beta$ stable NS matter. The estimated DM-electron scattering cross-section in this work is stringent compared to the current direct detection experimental probe. We then compute the lower limit on the halo velocity of DM for the four pulsars from the knowledge of the upper limit on effective temperature of the individual pulsars. We also extend our work to calculate the value of the effective temperature with the different models using the fitted values of the halo velocity of DM of the four pulsars with respect to their distances from the galactic center. Our findings are consistent with the analysis of the observed data.

   hep-phastro-ph.HEnucl-th3 citations
7. 07*

   QCD corrections to the Darwin coefficient in inclusive semileptonic $B\to X_u\ell {\bar{\nu }}_{\ell }$ decays

   Daniel Moreno🇨🇭

   In this paper we compute ${\alpha }_s$ corrections to the matching coefficients of the dimension six operators in the Heavy Quark Expansion of the inclusive semileptonic heavy hadron decay rate and leptonic invariant mass spectrum with a massless quark and both a massive or massless lepton in the final state, analytically. The obtained results can be applied to the inclusive semileptonic $B\to X_u\ell {\bar{\nu }}_{\ell }$ ($\ell =e,\mu ,\tau$) and $D\to X\ell {\bar{\nu }}_{\ell }$ ($\ell =e,\mu$) decays. The main application of our results is the background subtraction of the $B\to X_u\ell {\bar{\nu }}_{\ell }$ decay in the measurement of the $B\to X_c\ell {\bar{\nu }}_{\ell }$ decay, which is important for the precise extraction of $V_{cb}$ and $R(D^{(\ast )})$. They also play a role in the computation of lifetimes of heavy hadrons.

   hep-phPRD(2024)·7 citations
8. 08*

   Cold isospin asymmetric baryonic rich matter in nonlocal NJL-like models

   J. P. Carlomagno🇦🇷 · D. Gomez Dumm🇦🇷 · N. N. Scoccola🇦🇷

   We study the features of low energy strong interactions for a system at zero temperature and finite baryon and isospin chemical potentials, in the framework of a Nambu--Jona-Lasinio-like model that includes nonlocal four-point interactions. We analyze the phase transitions corresponding to chiral symmetry restoration and pion condensation, comparing our results with those obtained from local NJL-like models and lattice QCD calculations.

   hep-phPRD(2024)·9 citations
9. 09*

   Dynamics of identified particles production in oxygen-oxygen collisions at \sqrt{s_{\mathrm{NN}} = 7 TeV using EPOS4

   A.M. Khan🇨🇳 · M.U. Ashraf🇺🇸 · H.M. Alfanda🇨🇳 · M. Uzair. Aslam🇵🇰

   The Large Hadron Collider (LHC) aims to inject oxygen (${}^{16}O$) ions in the next run into its experiments. This include the anticipated one-day physics run focusing on $OO$ collisions at center-of-mass energy \sqrt{s_{\mathrm{NN}} = 7 Tev. In this study, we have used recently developed version of the EPOS (EPOS4) to study the production of identified particles (${\pi }^{\pm }$, $K^{\pm }$ and $p(\overline{p})$) in $OO$ collisions at 7 Tev. Predictions of transverse momentum ($p_T$) spectra, $⟨p_T⟩$, integrated yield (dN/dy) for different centrality classes are studied. To provide insight into the collective nature of the produced particles, we look into the $p_T$-differential particle ratios ($K/\pi$ and $p/\pi$) and $p_T$-integrated particle ratios to (${\pi }^{+}+{\pi }^{-}$) as a function of charge particle multiplicity. The shape of the charge particle multiplicity ($dN/d\eta$) and $⟨p_T⟩$ is well described by the EPOS4. The EPOS4 predictions for the ratios of $K/\pi$ and $p/\pi$ exhibit a systematic overestimation compared to the observed trends as a function of charged-particle multiplicity. Interestingly, the $OO$ results of $p_T$-integrated particle ratios shows a clear final state multiplicity overlap with $pp$, $p-Pb$ and $Pb-Pb$ collisions. EPOS4 mimics signs of collectivity and is one of the suitable candidates to study ultra-relativistic heavy-ion collisions. Furthermore, the foreseen data from $OO$ collisions at the LHC, when available, will help to better understand the heavy-ion-like behavior in small systems as well as help to put possible constraints on the model parameters.

   hep-phEPJA(2024)·9 citations
10. 10*

    Dark population transfer mechanism for sterile neutrino dark matter

    George M. Fuller🇺🇸 · Lukáš Gráf🇺🇸 · Amol V. Patwardhan🇺🇸 · Jacob Spisak🇺🇸

    We present a mechanism for producing a cosmologically-significant relic density of one or more sterile neutrinos. This scheme invokes two steps: First, a population of "heavy" sterile neutrinos is created by scattering-induced decoherence of active neutrinos; Second, this population is transferred, via sterile neutrino self-interaction-mediated scatterings and decays, to one or more lighter mass ($\sim 10\mathrm{keV}$ to $\sim 1\mathrm{GeV}$) sterile neutrinos that are far more weakly (or not at all) mixed with active species and could constitute dark matter. Dark matter produced this way can evade current electromagnetic and structure-based bounds, but may nevertheless be probed by future observations.

    hep-phastro-ph.COPRL(2024)·16 citations
11. 11*

    ${\chi }_{c2}$ tensor meson transition form factors in the light front approach

    Izabela Babiarz🇵🇱 · Roman Pasechnik🇸🇪 · Wolfgang Schäfer🇵🇱 · Antoni Szczurek🇵🇱

    We continue our work on the light-front formulation of quarkonium ${\gamma }^{\ast }\gamma$ transition form factors, extending the formalism to $J^{PC}=2^{++}$ tensor meson states. We present an analysis of ${\gamma }^{\ast }\gamma \to {\chi }_{c2}$ transition amplitude and the pertinent helicity form factors. Our relativistic formalism is based on the light-front quark-antiquark wave function of the quarkonium. We calculate the two-photon decay width as well as three independent ${\gamma }^{\ast }\gamma$ transition form factors for $J_z=0,1,2$ as a function of photon virtuality $Q^2$. We compare our results for the two-photon decay width to the recently measured ones by the Belle and BES III collaborations. Even when including relativistic corrections, a very small $\Gamma (\lambda =0)/\Gamma (\lambda =2)\sim 10^{-3}$ ratio is found which is beyond present experimental precision. We also present the form factors as a function of photon virtuality and compare them to the sparse experimental data on the so-called off-shell width. The formalism presented here can be used for other $2^{++}$ mesons, excited charmonia or bottomonia or even light $q\bar{q}$-mesons.

    hep-phJHEP(2024)·3 citations
12. 12*

    Neutrino phenomenology and keV dark matter in 2HDM with $A_4$ symmetry

    V. V. Vien🇻🇳

    We propose a minimal extended seesaw scheme based on the discrete symmetry $A_4\times Z_4\times Z_2\times Z_8$ which can successfully address neutrino phenomenology and keV sterile neutrino dark matter. The lepton mass hierarchy is naturally achieved. Active neutrino mixing angles can reached the best-fit points with the predictive Dirac CP violation phase. The active-sterile mixing matrix elements are small enough to access the observed cosmological dark matter abundance constraint with keV sterile neutrino dark matter. The effective neutrino masses are predicted to be in the ranges of the recent experimental limits.

    hep-phPTEP(2024)·8 citations
13. 13*

    QCD parameters and SM-high precision from $e^{+}{e}^{-}$ to Hadrons: Updated

    Stephan Narison (LUPM CNRS/IN2P3, Univ. Montpellier, and iHEPMAD, Univ. Antananarivo - MG)🇫🇷

    1. I update my previous comparison of the theoretical value of the muon anomaly with the new measurement and found $\Delta a_{\mu }\equiv a_{\mu }^{exp}-a_{\mu }^{th}=(143\pm 42_{th}\pm 22_{exp})\times 10^{-11}$ which is about 3$\sigma$ discrepancy between the SM predictions and experiment. 2. I improve the estimate of QCD power corrections up to dimension D=12 and provide a new estimate of the ones up to D=20 within the SVZ expansion by combining the ratio of the Laplace sum rules (LSR) with the BNP $\tau$-like decay moments for the I=1 vector current. The results in Table 1 confirm a violation of the factorization of the four-quark condensates and the value of the gluon one $<{\alpha }_s{G}^2>$ from some other sources. Up to D=20, I there is not any factorial nor exponential growth of the size of these power corrections. 3. I use these new values of power corrections to extract ${\alpha }_s$ from the BNP lowest moment. To order ${\alpha }_s^4$, I find within the SVZ expansion: ${\alpha }_s(M_{\tau })=0.3081(50{)}_{fit}(71{)}_{{\alpha }_s^5}$ [resp. $0.3260(47{)}_{fit}(62{)}_{{\alpha }_s^5}]$ implying ${\alpha }_s(M_Z)=0.1170(6)(3{)}_{evol}$ [resp. $0.1192(6)(3{)}_{evol}$] for Fixed Order (FO) [resp. Contour Improved (CI)] PT series. They lead to the mean: ${\alpha }_s(M_{\tau }){|}_{SVZ}=0.3179(58{)}_{fit}(81{)}_{syst}$ and ${\alpha }_s(M_Z){|}_{SVZ}=0.1182(12)(3{)}_{evol}$ where the systematic error(syst) takes into account the discrepancy between FO and CI. Using the lowest BNP moment, we also obtain from the vector (V) component of $\tau$-decay the mean: ${\alpha }_s(M_{\tau }){|}_{\tau ,V}=0.3219(52)(91{)}_{syst}$ giving: ${\alpha }_s(M_Z){|}_{\tau ,V}=0.1187(13)(3{)}_{evol}$. The average of the two determinations leads to: ${\alpha }_s(M_{\tau })=0.3198(72)$ and ${\alpha }_s(M_Z)=0.1185(9)(3{)}_{evol}$. 4. Some contributions beyond the SVZ expansion ($1/Q^2$, instantons and duality violation) expected to be small are discussed in Sections 10,11.

    hep-phhep-exhep-latNPA(2024)·5 citations
14. 14*

    Perturbative reheating and thermalization of pure Yang-Mills plasma

    Kyohei Mukaida🇯🇵 · Masaki Yamada🇯🇵

    We investigate the thermalization of high-energy particles injected from the perturbative decay of inflaton during the pre-thermal phase of reheating in detail. In general, thermalization takes a relatively long time in a low-temperature plasma; therefore, the instantaneous thermalization approximation is not justified, even for the reheating of the Standard Model (SM) sector. We consider a pure Yang-Mills (YM) theory as an approximation of the SM sector or a possible dark sector, considering the Landau-Pomeranchuk-Migdal effect, a quantum interference effect in a finite temperature plasma. We perform the first numerical calculation to solve the time evolution of the system, including the redshift due to the expansion of the Universe, and show the details of the temperature evolution near the maximum and the behavior of the quasi-attractors at later times. The maximal temperature $T_{\text{max}}$ and time scale $t_{\text{max}}$ are determined quantitatively, such as $T_{\text{max}}\simeq 0.05\times ({\Gamma }_I{M}_{\text{Pl}}^2/m_I^3{)}^{2/5}{m}_I$ and $t_{\text{max}}\simeq 2\times 10^3\times ({\Gamma }_I{M}_{\text{Pl}}^2/m_I^3{)}^{-3/5}{m}_I^{-1}$ in the SM-like system, where $m_I$ and ${\Gamma }_I$ are the mass and decay rate of inflaton. We also provide a similar formula for pure $\mathrm{SU}(N)$ and $\mathrm{SO}(N)$ YM theories for general values of $N$ and coupling constant $\alpha$, including $T_{\text{max}}\propto {\alpha }^{4/5}$ and $t_{\text{max}}\propto N^{-2}{\alpha }^{-16/5}$ behaviors and their numerical coefficients. The thermalization occurs in a finite time scale, resulting in a lower maximal temperature of the Universe after inflation than that under the instantaneous thermalization approximation.

    hep-phastro-ph.COhep-thJHEP(2024)·13 citations
15. 15*

    Visible GeV ALP from TeV Vector-like Leptons

    Arturo de Giorgi🇪🇸 · Marta Fuentes Zamoro🇪🇸 · Luca Merlo🇪🇸

    We present a model where a GeV axion-like-particle (ALP) is predicted in a large portion of the parameter space due to the presence of explicit Peccei-Quinn symmetry-breaking terms in an exotic leptonic sector. The latter provides a solution to the muon $g-2$ anomaly, within the framework of the Linear Seesaw neutrino mechanism. The spectrum is extended by a complex scalar singlet only transforming under the Peccei-Quinn symmetry, which generates the ALP. Its couplings with fermions can continuously span over many orders of magnitude, which constitutes a specific feature of this model in contrast to generic ultraviolet constructions. Interestingly, these couplings are suppressed by the ALP characteristic scale that can be as low as the TeV scale, which represents a novel feature of the model and opens up to several phenomenological consequences.

    hep-phFortsch.Phys.·12 citations
16. 16*

    An optimized basis for hadronic light-by-light scattering

    Martin Hoferichter🇨🇭 · Peter Stoffer🇨🇭 · Maximilian Zillinger🇨🇭

    We present a new basis for the hadronic light-by-light (HLbL) tensor that is optimized for the evaluation of narrow-resonance contributions to HLbL scattering in the anomalous magnetic moment of the muon. As main advantage, kinematic singularities are manifestly absent for pseudoscalar, scalar, and axial-vector states, while the remaining singularities for tensor resonances are minimized, even avoided for special cases, and simple crossing relations among the scalar functions maintained. We scrutinize the properties of this new basis for the scalar-QED pion box, demonstrating that the partial-wave convergence even slightly improves compared to our previous work, and discuss the physical sum rules that ensure basis independence of the HLbL contribution. Finally, we provide explicit expressions for narrow (pseudo-)scalar, axial-vector, and tensor intermediate states in terms of their respective transition form factors.

    hep-phhep-exhep-latnucl-thJHEP(2024)·57 citations
17. 17*

    Seeing Double: Calibrating Two Jets at Once

    Rikab Gambhir🇺🇸 · Benjamin Nachman🇺🇸

    Jet energy calibration is an important aspect of many measurements and searches at the LHC. Currently, these calibrations are performed on a per-jet basis, i.e. agnostic to the properties of other jets in the same event. In this work, we propose taking advantage of the correlations induced by momentum conservation between jets in order to improve their jet energy calibration. By fitting the $p_T$ asymmetry of dijet events in simulation, while remaining agnostic to the $p_T$ spectra themselves, we are able to obtain correlation-improved maximum likelihood estimates. This approach is demonstrated with simulated jets from the CMS Detector, yielding a $3$-$5\%$ relative improvement in the jet energy resolution, corresponding to a quadrature improvement of approximately 35\%.

    hep-phhep-exphysics.data-anPRD(2024)·4 citations
18. 18*

    New Mass Window for Primordial Black Holes as Dark Matter from Memory Burden Effect

    Ana Alexandre🇩🇪 · Gia Dvali🇩🇪 · Emmanouil Koutsangelas🇩🇪

    The mass ranges allowed for Primordial Black Holes (PBHs) to constitute all of Dark Matter (DM) are broadly constrained. However, these constraints rely on the standard semiclassical approximation which assumes that the evaporation process is self-similar. Quantum effects such as memory burden take the evaporation process out of the semiclassical regime latest by half-decay time. What happens beyond this time is currently not known. However, theoretical evidence based on prototype models indicates that the evaporation slows down thereby extending the lifetime of a black hole. This modifies the mass ranges constrained, in particular, by BBN and CMB spectral distortions. We show that previous constraints are largely relaxed when the PBH lifetime is extended, making it possible for PBHs to constitute all of DM in previously excluded mass ranges. In particular, this is the case for PBHs lighter than $10^9$g which enter the memory burden stage before BBN and are still present today as DM.

    hep-phastro-ph.COgr-qchep-thPRD(2024)·107 citations
19. 19*

    Non-nucleonic degrees of freedom and the spin structure of the deuteron

    Misak M Sargsian🇺🇸

    Electro-disintegration of the deuteron at large $Q^2$ currently represents on of the most promising reactions which allows to probe the bound nuclear state at internal momenta comparable to the rest mass of the nucleon. Large internal momentum in this case makes non-nuncleonic states energetically more feasible and the question that we address is what are the signatures that will indicate the existence of such states in the ground state of the nuclear wave function. To probe such states we developed a light-front formalism for relativistic description of a composite pseudo-vector system in which emerging proton and neutron are observed in electro-disintegration reaction. In leading high energy approximation our calculations show the possibility of the existence of a new ``incomplete" P-state-like structure in the deuteron at extremely large internal momenta. The incompleteness of the observed P-state violates the angular condition for the momentum distribution, which can happen only if the deuteron contains non-nucleonic structures, such as $\Delta \Delta$, $N^{\ast }N$ or hidden color components. Because such states have distinctive angular momentum ($l=1$) they significantly modify the polarization properties of the deuteron wave function. As a result in addition to angular anisotropy of the LF momentum distribution of the nucleon in the deuteron one predicts strong modification of the tensor polarization asymmetry of the deuteron beyond the S- and D- wave predictions at large internal momenta in the deuteron.

    ↳ nucl-thhep-phnucl-exPoS(2024)·0 citations
20. 20*

    A proposed PKU-Muon experiment for muon tomography and dark matter search

    Xudong Yu🇨🇳 · Zijian Wang🇨🇳 · Cheng-en Liu🇨🇳 · Yiqing Feng🇨🇳 · Jinning Li🇨🇳 · Xinyue Geng🇨🇳 · Yimeng Zhang🇨🇳 · Leyun Gao🇨🇳 · Ruobing Jiang🇨🇳 · Youpeng Wu🇨🇳 · Chen Zhou🇨🇳 · Qite Li🇨🇳 and 4 other authors

    We propose here a set of new methods to directly detect light mass dark matter through its scattering with abundant atmospheric muons or accelerator beams. Firstly, we plan to use the free cosmic-ray muons interacting with dark matter in a volume surrounded by tracking detectors, to trace possible interaction between dark matter and muons. Secondly, we will interface our device with domestic or international muon beams. Due to much larger muon intensity and focused beam, we anticipate the detector can be made further compact and the resulting sensitivity on dark matter searches will be improved. Furthermore, we will measure precisely directional distributions of cosmic-ray muons, either at mountain or sea level, and the differences may reveal possible information of dark matter distributed near the earth. Specifically, our methods can have advantages over `exotic' dark matters which are either muon-philic or slowed down due to some mechanism, and sensitivity on dark matter and muon scattering cross section can reach as low as microbarn level.

    ↳ hep-exhep-phphysics.app-phphysics.ins-detPRD(2024)·15 citations
21. 21*

    Modular forms and hierarchical Yukawa couplings in heterotic Calabi-Yau compactifications

    Keiya Ishiguro🇯🇵 · Tatsuo Kobayashi🇯🇵 · Satsuki Nishimura🇯🇵 · Hajime Otsuka🇯🇵

    We study the modular symmetry in heterotic string theory on Calabi-Yau threefolds. In particular, we examine whether moduli-dependent holomorphic Yukawa couplings are described by modular forms in the context of heterotic string theory with standard embedding. We find that $SL(2,\mathbb{Z})$ modular symmetry emerges in asymptotic regions of the Calabi-Yau moduli space. The instanton-corrected holomorphic Yukawa couplings are then given by modular forms under $SL(2,\mathbb{Z})$ or its congruence subgroups such as ${\Gamma }_0(3)$ and ${\Gamma }_0(4)$. In addition to the modular symmetry, it turns out that another coupling selection rule controls the structure of holomorphic Yukawa couplings. Furthermore, the coexistence of both the positive and negative modular weights for matter fields leads to a hierarchical structure of matter field Kähler metric. Thus, these holomorphic modular forms and the matter field Kähler metric play an important role in realizing a hierarchical structure of physical Yukawa couplings.

    ↳ hep-thhep-phJHEP(2024)·12 citations
22. 22*

    Variable Mass and the Noisy Feynman Propagator in Scalar Fields

    Allan Tameshtit

    We utilize a mass independent Klein-Gordon equation that is first order in a variable that plays the role of time, the approach taken in parametric time formulations. Using concepts from semigroup evolution, we examine the sign of a noisy Feynman propagator in a quantum field theory, namely, scalar electrodynamics.

    ↳ quant-phhep-phhep-thSci.Rep.(2024)·0 citations
23. 23*

    Sharpening the dark matter signature in gravitational waveforms II: Numerical simulations with the NbodyIMRI code

    Bradley J. Kavanagh🇪🇸 · Theophanes K. Karydas🇳🇱 · Gianfranco Bertone🇳🇱 · Pierfrancesco Di Cintio🇮🇹 · Mario Pasquato🇨🇦

    Future gravitational wave observatories can probe dark matter by detecting the dephasing in the waveform of binary black hole mergers induced by dark matter overdensities. Such a detection hinges on the accurate modelling of the dynamical friction, induced by dark matter on the secondary compact object in intermediate and extreme mass ratio inspirals. In this paper, we introduce NbodyIMRI, a new publicly available code designed for simulating binary systems within cold dark matter `spikes'. Leveraging higher particle counts and finer timesteps, we validate the applicability of the standard dynamical friction formalism and provide an accurate determination of the maximum impact parameter of particles which can effectively scatter with a compact object, across various mass ratios. We also show that in addition to feedback due to dynamical friction, the dark matter also evolves through a `stirring' effect driven by the time-dependent potential of the binary. We introduce a simple semi-analytical scheme to account for this effect and demonstrate that including stirring tends to slow the rate of dark matter depletion and therefore enhances the impact of dark matter on the dynamics of the binary.

    ↳ gr-qcastro-ph.COhep-phPRD(2025)·45 citations
24. 24*

    Exploring primordial black holes and gravitational waves with R-symmetric GUT Higgs inflation

    Nadir Ijaz🇵🇰 · Mansoor Ur Rehman🇵🇰

    This study investigates the realization of R-symmetric Higgs inflation within the framework of no-scale-like supergravity, aiming to elucidate the formation of primordial black holes and observable gravitational waves within a class of GUT models. We explore the possibility of an ultra-slow-roll phase in a hybrid inflation framework, where the GUT Higgs field primarily takes on the role of the inflaton. The amplification of the scalar power spectrum gives rise to scalar-induced gravitational waves and the generation of primordial black holes. The predicted stochastic gravitational wave background falls within the sensitivity range of existing and upcoming gravitational wave detectors, while primordial black holes hold the potential to explain the abundance of dark matter. Furthermore, we highlight the significance of the leading-order nonrenormalizable term in the superpotential of achieving inflationary observables consistent with the latest experimental data. Additionally, the predicted range of the tensor-to-scalar ratio, a key measure of primordial gravitational waves, lies within the observational window of future experiments searching for B-mode polarization patterns in cosmic microwave background data.

    ↳ astro-ph.COhep-phPLB(2025)·16 citations
25. 25*

    Two-dimensional Lorentz-violating Casimir effect

    K. E. L. de Farias🇧🇷 · M. A. Anacleto🇧🇷 · F. A. Brito🇧🇷 · E. Passos🇧🇷 · Herondy Mota🇧🇷

    In this study, we consider the four-dimensional Maxwell electrodynamics extended with CPT-even Myers-Pospelov Lorentz-violating dimension-six operators to investigate the associated two-dimensional properties in the context of quantum vacuum fluctuation effects, namely, the Casimir effect. Upon projecting out the 4D theory down to a 2D theory we obtain analogs of these operators leading to a modified dispersion relation in a Lorentz invariance violation (LIV) scalar model equivalent to the electromagnetic theory. By making use of the modified dispersion relation, we derive exact analytic expressions for the Casimir energy and force induced by imposing Dirichlet boundary conditions on the scalar field. In the regime where the LIV parameter becomes very small, we recover known results for the Casimir energy and force plus correction terms due to the LIV.

    ↳ hep-thgr-qchep-phPLB(2024)·3 citations
26. 26*

    Towards multiloop local renormalization within Causal Loop-Tree Duality

    Jose Rios-Sanchez🇪🇸 · German Sborlini🇪🇸

    Renormalization is a well-known technique to get rid of ultraviolet (UV) singularities. When relying on Dimensional Regularization (DREG), these become manifest as $ϵ$-poles, allowing to define counter-terms with useful recursive properties. However, this procedure requires to work at \emph{integral-level} and poses difficulties to achieve a smooth combination with semi-numerical approaches. This article is devoted to the development of an integrand-level renormalization formalism, better suited for semi or fully numerical calculations. Starting from the Loop-Tree Duality (LTD), we keep the causal representations of the integrands of multiloop Feynman diagrams and explore their UV behaviour. Then, we propose a strategy that allows to build local counter-terms, capable of rendering the expressions integrable in the high-energy limit and in four space-time dimensions. Our procedure was tested on diagrams up to three-loops, and we found a remarkably smooth cancellation of divergences. The results of this work constitute a powerful step towards a fully local renormalization framework in QFT.

    ↳ hep-thhep-phPRD(2024)·15 citations
27. 27*

    Quark stars in massive gravity might be candidates for the mass gap objects

    J. Sedaghat🇮🇷 · B. Eslam Panah🇮🇷 · R. Moradi🇨🇳 · S. M. Zebarjad🇮🇷 · G. H. Bordbar🇮🇷

    We have investigated the structural properties of strange quark stars (SQSs) in a modified theory of gravity known as massive gravity. In order to obtain the equation of state (EOS) of strange quark matter, we have employed a modified version of the Nambu-Jona-Lasinio model (MNJL) which includes a combination of NJL Lagrangian and its Fierz transformation by using weighting factors ($1-\alpha$) and $\alpha$. Additionally, we have also calculated dimensionless tidal deformability ($\Lambda$) in massive gravity. To constrain the allowed values of the parameters appearing in massive gravity, we have imposed the condition ${\Lambda }_{1.4M_{\odot }}\lesssim 580$. Notably, in the MNJL model, the value of $\alpha$ varies between zero and one. As $\alpha$ increases, the EOS becomes stiffer, and the value of $\Lambda$ increases accordingy. We have demonstrated that by softening the EOS with increasing the bag constant, one can obtain objects in massive gravity that not only satisfy the constraint \Lambda_{1.4 {M}% _{\odot }}\lesssim580, but they also fall within the unknown mass gap region ($2.5M_{\odot }-5M_{\odot }$). To establish that the obtained objects in this region are not black holes, we have calculated Schwarzschild radius, compactness, and ${\Lambda }_{M_{TOV}}$ in massive gravity.

    ↳ gr-qcastro-ph.HEhep-phhep-thEPJC(2024)·21 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.