Wed·Jun 14, 2023Wednesday·June 14, 2023

1. 01*

   Dark Matter Is The New BBN

   Dan Hooper🇺🇸 · Huangyu Xiao🇺🇸

   Measurements of the primordial element abundances provide us with an important probe of our universe's early thermal history, allowing us to constrain the expansion rate and composition of our universe as early as $\sim 1\mathrm{s}$ after the Big Bang. Prior to this time, we have essentially no empirical information on which to base any such claims. In this paper, we imagine a future time in which we have not only detected the particles that make up the dark matter, but have measured their mass and annihilation cross section with reasonable precision. In analogy to the light element abundances, the dark matter abundance in this scenario could be used to study and constrain the expansion rate and composition of our universe at the time of dark matter freeze out, which for a standard thermal relic occurs at $T_f\sim m_{\chi }/20$, corresponding to $t\sim 4\times 10^{-10}\mathrm{s}\times (\mathrm{TeV}/m_{\chi }{)}^2$, many orders of magnitude prior to the onset of Big Bang nucleosynthesis. As examples, we consider how such measurements could be used to constrain scenarios which feature exotic forms of radiation or matter, a ultralight scalar, or modifications to gravity, each of which have the potential to be much more powerfully probed with dark matter than with the light element abundances.

   hep-phastro-ph.COPhys.Dark Univ.(2023)·6 citations
2. 02*

   Neutrino oscillation measurements with KamLAND and JUNO in the presence of scalar NSI

   Aman Gupta🇮🇳 · Debasish Majumdar🇮🇳 · Suprabh Prakash🇮🇳

   Determination of neutrino mass ordering and precision measurement of neutrino oscillation parameters are the foremost goals of the JUNO experiment. Here, we explore the effects of scalar non-standard interactions (sNSI) on the electron anti-neutrino survival probability measured by JUNO. sNSI appear as corrections to the neutrino mass term in the Hamiltonian. We have considered the simplest scenario where there is only one NSI (${\eta }_{ee}$) present in the theory. Our results show that sNSI can have a significant effect on neutrino oscillation probabilities at the medium- and long-baseline reactor experiments. We fit KamLAND data assuming non-zero sNSI in theory and find that {\it estimates of $\Delta m_{21}^2$ and ${\theta }_{12}$ from KamLAND deviate significantly from their standard best-fit values} if one assumes sNSI in the theory. ${\eta }_{ee}\in [-1.0,1.0]$ is allowed by KamLAND. JUNO cannot constrain sNSI but it can robustly measure $\Delta m_{21}^2$ and ${\theta }_{12}$ even when they differ widely from their current best-fit values. {\it Our work highlights the necessity of global analysis of constraints on sNSI and standard two-flavour oscillation parameters before arduous three-flavour questions such as neutrino mass ordering or CP violation in their presence are attempted.

   hep-phPhys.Dark Univ.(2025)·22 citations
3. 03*

   Investigation of $\Lambda (1405)$ as a molecular pentaquark state

   K. Azizi🇮🇷 · Y. Sarac🇹🇷 · H. Sundu🇹🇷

   $\Lambda (1405)$ is one of the interesting particles with its unclear structure and distinct properties. It has a light mass compared to its non-strange counterpart, despite the strange quark it carries. This situation puts the investigation of this resonance among the hot topics in hadron physics and collects attention to clarify its properties. In this study, we focus on the calculation of the mass and residue of the $\Lambda (1405)$ resonance within the framework of QCD sum rules. We assign a structure in the form of a molecular pentaquark composed from admixture of $K^{-}$ meson-proton and ${\bar{K}}^0$ meson-neutron. Using an interpolating current in this form, the masses and the current coupling constant are attained as $m=1406\pm 128\mathrm{MeV}$ and $\lambda =(3.35\pm 0.35)\times 10^{-5}{\mathrm{GeV}}^6$ for $\text{slashed}q$ and $m=1402\pm 141\mathrm{MeV}$ and $\lambda =(4.08\pm 1.08)\times 10^{-5}{\mathrm{GeV}}^6$ for $I$ Lorentz structures entering the calculations, respectively. The obtained mass values agree well with the experimental data supporting the plausibility of the considered structure.

   hep-phhep-exhep-latEPJC(2024)·10 citations
4. 04*

   Bound-free pair production mechanism in Pb-p collisions at LHC

   Melek Yilmaz Şengül🇹🇷

   In this work, cross section calculations of bound-free pair production (BFPP) are done for the mechanism in Pb-p collisions at LHC. BFPP cross section for the asymmetric collisions of Pb-p at the center of mass energies of $\sqrt{s_{NN}}=5,02TeV$ and $\sqrt{s_{NN}}=8,16TeV$ is computed. In order to reach the exact results, Monte Carlo integration techniques are utilized to calculate the lowest-order Feynman diagrams amplitudes via the lowest order perturbation theory. Also, in this work our cross section results for BFPP mechanism in Pb-p collisions at LHC are compared with BFPP cross section results obtained in literature, which are reached for Pb-p collisions by using a simple scaling applied to scale BFPP cross section results in Pb-Pb collisions at LHC.

   hep-phActa Phys.Polon.B(2023)·0 citations
5. 05*

   Interactions of the ${\chi }_{c1}(4274)$ state with light mesons

   A. L. M. Britto🇧🇷 · L. M. Abreu🇧🇷 · F. S. Navarra🇧🇷

   We investigate the interactions of the ${\chi }_{c1}(4274)$ state with light mesons in the hot hadron gas formed in heavy ion collisions. The vacuum and thermally-averaged cross sections of production of ${\chi }_{c1}(4274)$ accompanied by light pseudoscalar and light vector mesons as well as the corresponding inverse processes are estimated within the context of an effective Lagrangian approach. The results suggest non-negligible thermal cross-sections, with larger magnitudes for most of the suppression reactions than those for production. This might be a relevant feature to be considered in the analysis of future data collected in heavy ion collisions.

   hep-phPRD(2023)·6 citations
6. 06*

   Constraining dark boson decay using neutron stars

   Wasif Husain🇦🇺 · Dipan Sengupta🇦🇺 · A W Thomas🇦🇺

   Inspired by the well known anomaly in the life time of the neutron, we investigate its consequences inside neutron stars. We first assess the viability of the neutron decay hypothesis suggested by Fornal and Grinstein within neutrons tars, in terms of the equation of state and compatibility with observed properties. This is followed by an investigation of the constraint in formation on neutron star cooling can place on the decay rate of the dark boson into standard model particles, in the context of various BSM ideas.

   hep-phUniverse(2023)·11 citations
7. 07*

   Investigating $D_s^{+}\to {\pi }^0{\ell }^{+}{\nu }_{\ell }$ decay process within QCD sum rule approach

   Hai-Jiang Tian🇨🇳 · Hai-Bing Fu🇨🇳 · Tao Zhong🇨🇳 · Xuan Luo🇨🇳 · Dan-Dan Hu🇨🇳 · Yin-Long Yang🇨🇳

   In this paper, the semileptonic decays $D_s^{+}\to {\pi }^0{\ell }^{+}{\nu }_{\ell }$ with $\ell =(e,\mu )$ are investigated by using the light-cone sum rule approach. Firstly, the neutral meson mixing scheme between ${\pi }^0$, $\eta$, ${\eta }^{\prime }$ and pseudoscalar gluonium $G$ is discussed in a unified way, which leads to the direct connection between two different channels for $D_s^{+}\to {\pi }^0{\ell }^{+}{\nu }_{\ell }$ and $D_s^{+}\to \eta {\ell }^{+}{\nu }_{\ell }$ by the ${\pi }^0-\eta$ mixing angle. Then we calculated the $D_s\to {\pi }^0$ transition form factors (TFFs) within QCD light-cone sum rule approach up to next-to-leading order correction. At the large recoil point, we have $f_{+}^{D_s^{+}{\pi }^0}(0)=0.0113_{-0.0019}^{+0.0024}$ and $f_{-}^{D_s^{+}{\pi }^0}(0)=0.0020_{-0.0009}^{+0.0008}$. Furthermore, the TFFs are extrapolated to the whole physical $q^2$-region by using the simplified $z(q^2)$-series expansion. The behaviors of TFFs and related three angular coefficient functions $a_{{\theta }_{\ell }}(q^2)$, $b_{{\theta }_{\ell }}(q^2)$ and $c_{{\theta }_{\ell }}(q^2)$ are given. The differential decay widths for $D_s^{+}\to {\pi }^0{\ell }^{+}{\nu }_{\ell }$ with respect to $q^2$ and $\cos {\theta }_{\ell }$ are presented, and also lead to the branching fractions $\mathcal{B}(D_s^{+}\to {\pi }^0{e}^{+}{\nu }_e)=2.60_{-0.51}^{+0.57}\times 10^{-5}$ and $\mathcal{B}(D_s^{+}\to {\pi }^0{\mu }^{+}{\nu }_{\mu })=2.58_{-0.51}^{+0.56}\times 10^{-5}$. These results show well agreement with the recent BESIII measurements and theoretical predictions. Then the differential distributions and integrated predictions for three angular observables, {\it i.e.} forward-backward asymmetries, $q^2$-differential flat terms and lepton polarization asymmetries are given separately. Lastly, we estimate the ratio for different decay channels ${\mathcal{R}}_{{\pi }^0/\eta }^{\ell }=1.108_{-0.071}^{+0.039}\times 10^{-3}$.

   hep-phPRD(2023)·11 citations
8. 08*

   Interplay between non-interfering neutrino exchange mechanisms and nuclear matrix elements in $0\nu \beta \beta$ decay

   Eligio Lisi🇮🇹 · Antonio Marrone🇮🇹 · Newton Nath🇮🇹

   We revisit the phenomenology of neutrinoless double beta ($0\nu \beta \beta$) decay mediated by non-interfering exchange of light and heavy Majorana neutrinos, in the context of current and prospective ton-scale experimental searches, as well as of recent calculations of nuclear matrix elements (NME) in different nuclear models. We derive joint upper bounds on the light and heavy contributions to $0\nu \beta \beta$ decay, for different sets of NME, through separate and combined data coming from the following experiments (and isotopes): KamLAND-Zen and EXO (Xe), GERDA, and MAJORANA (Ge) and CUORE (Te). We further consider three proposed projects that could provide, within current bounds, possible $0\nu \beta \beta$ decay signals at $>3\sigma$ level with an exposure of 10 ton years: nEXO (Xe), LEGEND (Ge) and CUPID (Mo). Separate and combined (Xe, Ge, Mo) signals are studied for different representative cases and NME sets, and the conditions leading to (non)degenerate light and heavy neutrino mechanisms are discussed. In particular, the role of heavy-to-light NME ratios in different isotopes is highlighted through appropriate graphical representations. By using different sets of "true" and "test" NME as a proxy for nuclear uncertainties, it is shown that the relative contributions of light and heavy neutrino exchange to $0\nu \beta \beta$ signals may be significantly biased in some cases. Implications for theoretical models connecting light and heavy Majorana neutrino masses are also briefly illustrated. These results provide further motivations to improve NME calculations, so as to better exploit the physics potential of future multi-isotope $0\nu \beta \beta$ searches at the ton scale.

   hep-phhep-exnucl-exnucl-thPRD(2023)·8 citations
9. 09*

   DIS dijet production at next-to-eikonal accuracy in the CGC

   Arantxa Tymowska🇵🇱 · Tolga Altinoluk🇵🇱 · Guillaume Beuf🇵🇱 · Alina Czajka🇵🇱

   In this work, we derive the cross-section for inclusive DIS dijet production at full next-to-eikonal order. We include the corrections that stem from taking a finite width of the target, the interaction of the quark with the transverse component of the background field and also the dynamics of the target.

   hep-phActa Phys.Polon.Supp.(2023)·1 citation
10. 10*

    Amplitude-assisted tagging of longitudinally polarised bosons using wide neural networks

    Michele Grossi🇨🇭 · Massimiliano Incudini🇯🇵 · Mathieu Pellen🇩🇪 · Giovanni Pelliccioli🇩🇪

    Extracting longitudinal modes of weak bosons in LHC processes is essential to understand the electroweak-symmetry-breaking mechanism. To that end, we propose a general method, based on wide neural networks, to properly model longitudinal-boson signals and hence enable the event-by-event tagging of longitudinal bosons. It combines experimentally accessible kinematic information and genuine theoretical inputs provided by amplitudes in perturbation theory. As an application we consider the production of a Z boson in association with a jet at the LHC, both at leading order and in the presence of parton-shower effects. The devised neural networks are able to extract reliably the longitudinal contribution to the unpolarised process. The proposed method is very general and can be systematically extended to other processes and problems.

    hep-phhep-exEPJC(2023)·13 citations
11. 11*

    Two-Loop Electron Factor Contribution to Lamb Shift in Muonium and Positronium

    Michael I. Eides🇺🇸 · Valery A. Shelyuto🇷🇺

    We calculate hard spin-independent contributions to energy levels in muonium and positronium which are due to radiatively corrected electron factor insertion in two-photon exchange diagrams. Calculation of these corrections is motivated by the new round of precise measurements of spin-independent transition frequencies in muonium and positronium.

    hep-phphysics.atom-phPLB(2023)·10 citations
12. 12*

    Forbidden dark matter annihilation into leptons with full collision terms

    Amin Aboubrahim🇩🇪 · Michael Klasen🇩🇪 · Luca Paolo Wiggering🇩🇪

    The standard approach of calculating the relic density of thermally produced dark matter based on the assumption of kinetic equilibrium is known to fail for forbidden dark matter models since only the high momentum tail of the dark matter phase space distribution function contributes significantly to dark matter annihilations. Furthermore, it is known that the computationally less expensive Fokker-Planck approximation for the collision term describing elastic scattering processes between non-relativistic dark matter particles and the Standard Model thermal bath breaks down if both scattering partners are close in mass. This, however, is the defining feature of the forbidden dark matter paradigm. In this paper, we therefore include the full elastic collision term in the full momentum-dependent Boltzmann equation as well as in a set of fluid equations that couple the evolution of the number density and dark matter temperature for a simplified model featuring forbidden dark matter annihilations into muon or tau leptons through a scalar mediator. On the technical side, we perform all angular integrals in the full collision term analytically and take into account the effect of dark matter self-interactions on the relic density. The overall phenomenological outcome is that the updated relic density calculation results in a significant reduction of the experimentally allowed parameter space compared to the traditional approach, which solves only for the abundance. In addition, almost the entire currently viable parameter space can be probed with CMB-S4, next-generation beam-dump experiments or at a future high-luminosity electron-position collider, except for the resonant region where the mediator corresponds to approximately twice the muon or tau mass.

    hep-phJCAP(2023)·17 citations
13. 13*

    Higgs Inflation at the Pole

    Simon Cléry🇫🇷 · Hyun Min Lee🇰🇷 · Adriana G. Menkara🇰🇷

    We propose a novel possibility for Higgs inflation where the perturbative unitarity below the Planck scale is ensured by construction and the successful predictions for inflation are accommodated. The conformal gravity coupling for the Higgs field leads to the proximity of the effective Planck mass to zero in the Jordan frame during inflation, corresponding to a pole in the Higgs kinetic term in the Einstein frame. Requiring the Higgs potential to vanish at the conformal pole in the effective theory in the Jordan frame, we make a robust prediction of the successful Higgs inflation. For a successful Higgs inflation at the pole, we take the running quartic coupling for the Higgs field to be small enough at the inflation scale, being consistent with the low-energy data, but we need a nontrivial extension of the SM with extra scalar or gauge fields in order to keep the running Higgs quartic coupling small during inflation. Performing the perturbative analysis of reheating with the known couplings of the SM particles to the Higgs boson, we show that a concrete realization of the Higgs pole inflation can be pinned down by the reheating processes with a general equation of state for the Higgs inflaton. We illustrate some extensions of the simple Higgs pole inflation to the general pole expansions, the running Higgs quartic coupling in the Standard Model and its extension with a singlet scalar field, a supergravity embedding of the Higgs pole inflation.

    hep-phastro-ph.COhep-thJHEP(2023)·11 citations
14. 14*

    Quantum Entanglement in Top Quark Pair Production

    Mira Varma🇺🇸 · O.K. Baker🇺🇸

    Top quarks, the most massive particles in the standard model, attract considerable attention since they decay before hadronizing. This presents physicists with a unique opportunity to directly investigate their properties. In this letter, we expand upon the work of G. Iskander, J. Pan, M. Tyler, C. Weber and O. K. Baker to demonstrate that even with the most massive fundamental particle, we see the same manifestation of entanglement observed in both electroweak and electromagnetic interactions. We propose that the thermal component resulting from protons colliding into two top quarks emerges from entanglement within the two-proton wave function. The presence of entanglement implies the coexistence of both thermal and hard scattering components in the transverse momentum distribution. We use published ATLAS and CMS results to show that the data exhibits the expected behavior.

    hep-phquant-phNPA(2024)·9 citations
15. 15*

    Pseudo-Goldstone dark matter in a radiative inverse seesaw scenario

    Kristjan Kannike🇪🇪 · Aleksei Kubarski🇪🇪 · Luca Marzola🇪🇪 · Antonio Racioppi🇪🇪

    We consider a scale-invariant inverse seesaw model with dynamical breaking of gauge symmetry and lepton number. In some regions of the parameter space, the Majoron - the pseudo-Goldstone of lepton number breaking - is a viable dark matter candidate. The bound on the Majoron decay rate implies a very large dilaton vacuum expectation value, which also results in a suppression of other dark matter couplings. Because of that, the observed dark matter relic abundance can only be matched via the freeze-in mechanism. The scalar field which gives mass to heavy neutrinos can play the role of the inflaton, resulting in a tensor-to-scalar ratio $r\lesssim 0.01$ for metric inflation and $r\lesssim 0.21$ for Palatini gravity.

    hep-phJHEP(2023)·10 citations
16. 16*

    Improving Euler-Heisenberg-Schwinger effective action with dressed photons

    Stefan Evans🇺🇸 · Johann Rafelski🇺🇸

    We implement a longstanding proposal by Weisskopf to apply virtual polarization corrections to the in/out external fields in study of the Euler-Heisenberg-Schwinger effective action. Our approach requires distinguishing the electromagnetic and polarization fields based on mathematical tools developed by Białynicki-Birula, originally for the Born-Infeld action. Our solution is expressed as a differential equation where the one-loop effective action serves as input. As a first result of our approach, we recover the higher-order one-cut reducible loop diagrams discovered by Gies and Karbstein.

    hep-phhep-thnucl-thquant-phActa Phys.Polon.A(2023)·4 citations
17. 17*

    Role of ${\lambda }_{h{H}^{+}{H}^{-}}$ in Higgs boson decays $h$ to $bs$ in the 2HDM

    F. Arco🇪🇸 · S. Heinemeyer🇪🇸 · M.J. Herrero🇪🇸

    Within the Two Higgs Doublet Model (2HDM) with $\mathcal{C}\mathcal{P}$ conservation and a softly broken $Z_2$ symmetry, we analyze the flavor changing Higgs decays $h\to bs$ ($bs$ refers jointly to the two decay channels $b\bar{s}$ and $\bar{b}s$), where $h$ is identified with the SM-like Higgs boson discovered at the LHC. We provide a comprehensive study of the decay width $\Gamma (h\to bs)$ with particular focus on the most relevant effects from the triple Higgs coupling ${\lambda }_{h{H}^{+}{H}^{-}}$. Furthermore, we consider all the relevant theoretical and experimental constraints to determine which predictions for the $\mathrm{BR}\left(h\to bs\right)$ are still allowed by the current data. We find that the predictions for $\mathrm{BR}\left(h\to bs\right)$ in types II and III can be several orders of magnitude smaller compared to the SM value. In contrast, in type I and IV we find that the predicted enhancements in the decay rates with respect to the SM of up to about 70% and 50%, respectively, are still allowed. We discuss how these deviations from the SM are caused by interference effects controlled by the coupling ${\lambda }_{h{H}^{+}{H}^{-}}$ which can be large for very heavy $H^{\pm }$. To better understand the role of ${\lambda }_{h{H}^{+}{H}^{-}}$ in the $h\to bs$ decay we derive and analyze here the analytical results for the $hbs$ one-loop effective vertex that is generated by integrating out the heavy $H^{\pm }$.

    hep-phPRD(2023)·5 citations
18. 18*

    Heavy quark radiation in an anisotropic hot QCD medium

    Jai Prakash🇮🇳 · Vinod Chandra🇮🇳 · Santosh K. Das🇮🇳

    The impact of momentum anisotropy on the heavy quarks (HQs) dynamics has been investigated in a hot QCD medium while considering both collisional and radiative processes within the ambit of the Fokker-Planck approach. The relative orientation of the HQs motion (momentum vector) with respect to the direction of anisotropy is responsible for the character of transport coefficients. Therefore, the drag and diffusion coefficients of the HQs are decomposed, respectively, into two and four components by considering a general tensor basis. Each component of the drag and diffusion coefficient of the HQs has been analyzed in detail. It is observed that the anisotropy has a significant impact on the transport coefficients of the HQ for both the collisional and the radiational processes. The nuclear suppression factor, $R_{AA}$, has been computed considering the anisotropic medium. It is observed that the momentum anisotropy affects the $R_{AA}$ of the HQs significantly in both elastic and inelastic cases.

    hep-phnucl-thPRD(2023)·24 citations
19. 19*

    Mapping and Probing Froggatt-Nielsen Solutions to the Quark Flavor Puzzle

    Claudia Cornella🇩🇪 · David Curtin🇨🇦 · Ethan T. Neil🇺🇸 · Jedidiah O. Thompson🇺🇸

    The Froggatt-Nielsen (FN) mechanism is an elegant solution to the flavor problem. In its minimal application to the quark sector, the different quark types and generations have different charges under a $U(1{)}_X$ flavor symmetry. The SM Yukawa couplings are generated below the flavor breaking scale with hierarchies dictated by the quark charge assignments. Only a handful of charge assignments are generally considered in the literature. We analyze the complete space of possible charge assignments with $|X_{q_i}|\le 4$ and perform both a set of Bayesian-inspired numerical scans and an analytical spurion analysis to identify those charge assignments that reliably generate SM-like quark mass and mixing hierarchies. The resulting set of top-20 flavor charge assignments significantly enlarges the viable space of FN models but is still compact enough to enable focused phenomenological study. We then apply our numerical methodology to demonstrate that these distinct charge assignments result in the generation of correlated flavor-violating four-quark operators characterized by significantly varied strengths, potentially differing substantially from the possibilities previously explored in the literature. Future precision measurement of $\Delta F=2$ observables, along with increasingly accurate SM predictions, may therefore enable us to distinguish among otherwise equally plausible FN charges, thus shedding light on the UV structure of the flavor sector.

    hep-phPRD(2025)·32 citations
20. 20*

    NNLL Resummation of Sudakov Shoulder Logarithms in the Heavy Jet Mass Distribution

    Arindam Bhattacharya🇺🇸 · Johannes K. L. Michel🇺🇸 · Matthew D. Schwartz🇺🇸 · Iain W. Stewart🇺🇸 · Xiaoyuan Zhang🇺🇸

    The heavy jet mass event shape has large perturbative logarithms near the leading order kinematic threshold at $\rho =\frac{1}{3}$. Catani and Webber named these logarithms Sudakov shoulders and resummed them at double-logarithmic level. A resummation to next-to-leading logarithmic level was achieved recently. Here, we extend the resummation using an effective field theory framework to next-to-next-to-leading logarithmic order and show how to combine it with the resummation of dijet logarithms. We also solve the open problem of an unphysical singularity in the resummed momentum space distribution, in a way similar to how it is resolved in the Drell-Yan $q_T$ spectrum: through a careful analysis of the kinematics and scale-setting in position space. The heavy jet mass Sudakov shoulder is the first observable that does not involve transverse momentum for which position space resummation is critical. These advances may lead to a more precise extraction of the strong coupling constant from $e^{+}{e}^{-}$ data.

    hep-phnucl-thJHEP(2023)·18 citations
21. 21*

    Running beyond ALPs: shift-breaking and CP-violating effects

    Supratim Das Bakshi🇪🇸 · Jonathan Machado-Rodríguez🇪🇸 · Maria Ramos🇪🇸

    We compute the renormalization group equations (RGEs) of the Standard Model effective field theory (EFT) extended with a real scalar singlet, up to dimension-five and one-loop accuracy. We compare our renormalization results with those found in the shift-symmetry preserving limit, which characterizes axion-like particles (ALPs). The matching and running equations below the electroweak scale are also obtained, including the mixing effects in the scalar sector. Such mixing leads to interesting phenomenological consequences that are absent in the EFT at the renormalizable level, namely new correlations among the triplet and quartic Higgs couplings are predicted. All RGEs obtained in this work are implemented in a new Mathematica package - ALPRunner, together with functions to solve the running numerically for an arbitrary set of UV parameters. As an application, we obtain the improved electric dipole moment constraints on particular regions of the singlet parameter space, and quantify the level of shift-breaking in these regions.

    hep-phhep-thJHEP(2023)·27 citations
22. 22*

    Reheating after Inflaton Fragmentation

    Marcos A. G. Garcia🇲🇽 · Mathias Pierre🇩🇪

    In the presence of self-interactions, the post-inflationary evolution of the inflaton field is driven into the non-linear regime by the resonant growth of its fluctuations. The once spatially homogeneous coherent inflaton is converted into a collection of inflaton particles with non-vanishing momentum. Fragmentation significantly alters the energy transfer rate to the inflaton's offspring during the reheating epoch. In this work we introduce a formalism to quantify the effect of fragmentation on particle production rates, and determine the evolution of the inflaton and radiation energy densities, including the corresponding reheating temperatures. For an inflaton potential with a quartic minimum, we find that the efficiency of reheating is drastically diminished after backreaction, yet it can lead to temperatures above the big bang nucleosynthesis limit for sufficiently large couplings. In addition, we use a lattice simulation to estimate the spectrum of induced gravitational waves, sourced by the scalar inhomogeneities, and discuss detectability prospects. We find that a Boltzmann approach allows to accurately predict some of the main features of this spectrum.

    hep-phastro-ph.COhep-thJCAP(2023)·48 citations
23. 23*

    Dark Matter Search with a Resonantly-Coupled Hybrid Spin System

    Kai Wei🇨🇳 · Zitong Xu🇨🇳 · Yuxuan He🇨🇳 · Xiaolin Ma🇨🇳 · Xing Heng🇨🇳 · Xiaofei Huang🇨🇳 · Wei Quan🇨🇳 · Wei Ji🇩🇪 · Jia Liu🇨🇳 · Xiao-Ping Wang🇨🇳 · Dmitry Budker🇩🇪 · Jiancheng Fang🇨🇳

    Recent advances in tabletop quantum sensor technology have enabled searches for nongravitational interactions of dark matter (DM). Traditional axion DM experiments rely on sharp resonance, resulting in extensive scanning time to cover a wide mass range. In this work, we present a broadband approach in an alkali-${}^{21}$Ne spin system. We identify two distinct hybrid spin-coupled regimes: a self-compensation (SC) regime at low frequencies and a hybrid spin resonance (HSR) regime at higher frequencies. By utilizing these two distinct regimes, we significantly enhance the bandwidth of ${}^{21}$Ne nuclear spin compared to conventional nuclear magnetic resonance, while maintaining competitive sensitivity. We present a comprehensive broadband search for axion-like dark matter, covering 5 orders of magnitude of Compton frequencies range within $[10^{-2},10^3]$ Hz. We set new constraints on the axion dark matter interactions with neutrons and protons, accounting for the effects of DM stochasticity. For the axion-neutron coupling, our results reach a low value of $|g_{ann}|\le 3\times 10^{-10}$ in the frequency range $[2\times 10^{-2},4]$ Hz surpassing astrophysical limits and providing the strongest laboratory constraints in the $[10,100]$ Hz range. For the axion-proton coupling, we offer the best terrestrial constraints for the frequency ranges $[2\times 10^{-2},5]$Hz and $[16,7\times 10^2]$ Hz.

    hep-phastro-ph.COhep-exphysics.atom-ph+1Rept.Prog.Phys.(2025)·49 citations
24. 24*

    Hydrodynamic theories for a system of weakly self-interacting classical ultra-relativistic scalar particles: microscopic derivations and attractors

    Gabriel S. Rocha🇧🇷 · Caio V. P. de Brito🇧🇷 · Gabriel S. Denicol🇧🇷

    We derive and investigate several hydrodynamic formalisms that emerge from a system of classical, ultra-relativistic scalar particles self-interacting via a quartic potential. The specific form of the total cross-section enables the analytical computation of all transport coefficients that appear in Navier-Stokes (NS), Bemfica-Disconzi-Noronha-Kovtun (BDNK), and second-order transient hydrodynamic theories. We solve all these formalisms in a Bjorken flow scenario and show that NS and BDNK theories display unphysical features when gradients become sufficiently large. This implies that these hydrodynamic approaches may not be suitable to describe the early stages of heavy ion collisions.

    ↳ nucl-thhep-phhep-thPRD(2023)·28 citations
25. 25*

    On the Anisotropy of the Stochastic Gravitational Wave Background from Sub-Horizon-Collapsed Primordial Black Hole Mergers

    Stefano Profumo🇺🇸 · Fengwei Yang🇺🇸

    We study the properties of the stochastic gravitational wave background (SGWB) resulting from the mergers of primordial black holes (PBH) that formed from the collapse of sub-horizon regions in the early universe. We adopt a model-independent approach, where we parameterize the fraction $f_H$ of the wavelength of the perturbation mode in units of the horizon radius when the patch starts to gravitationally collapse. Assuming a monochromatic spectrum of isocurvature perturbations and spherically-symmetric density perturbations, we investigate the isotropic SGWB energy density and angular power spectrum at various frequencies, PBH masses, and horizon size fractions. The key effect of sub-horizon formation is a change in the PBH mass function and formation redshift, which, in turn, affects gravitational wave (GW) observables. We find that sub-horizon PBH formation in general enhances the isotropic SGWB energy density and the absolute angular power spectrum. However, the quasi-monotonic increases in both quantities as $f_H$ decreases cease when the chirp mass of the binary PBHs reaches a mass threshold determined by the frequency of observation; the isotropic SGWB energy density spectrum significantly drops above the corresponding cutoff frequency.

    ↳ astro-ph.COhep-phPRD(2023)·9 citations
26. 26*

    Causality Criteria from Stability Analysis at Ultra-High Boost

    Shuvayu Roy🇮🇳 · Sukanya Mitra🇮🇳

    In this work, we have exclusively employed the linear stability analysis at ultra-high boost on two well-known stable-causal theories - second-order MIS and first-order BDNK, to identify the region of parameter space over which they are frame-invariantly stable and obey causal signal propagation. It has been shown that at near-luminal boost, stability criteria alone can provide the causality constraints on transport coefficients, which are identical to the asymptotic causality conditions, without actually going to the asymptotic limit of the theories. Thus, we present an alternative approach to derive the causality constraints, which is more appropriate for low-energy effective theories like relativistic hydrodynamics.

    ↳ hep-thhep-phnucl-thPRD(2024)·8 citations
27. 27*

    Gravitational and dark wave emission at binary merger

    Kunio Kaneta🇯🇵 · Kin-ya Oda🇯🇵 · Motohiko Yoshimura🇯🇵

    The recently proposed formalism of extended Jordan-Brans-Dicke gravity makes it possible to calculate energy loss rate due to both gravitational wave and scalar field (giving the origin of dark energy) wave emission at merger of a black hole and a neutron star; a binary system of no scalar hair and a star with the scalar charge. The scalar field emission changes orbit parameters of the binary system, thereby changes detectable gravitational wave emission. When neutron stars carry significantly large scalar charge, significant dark wave (namely, scalar field wave) emission occurs at the same time of gravitational wave emission. It is found that solutions of coupled differential equations predict non-vanishing remnant dark charge after the gravitational collapse. This gives two interesting possibilities: (1) the no-hair conjecture of black hole is violated, or (2) a bosonic cloud is formed outside the event horizon of black hole. The bosonic cloud proposed in the literature is a gigantic atom made of gravitationally bound dark energy quanta surrounding a black hole. One can either constrain, or even determine, parameters of extended Jordan-Brans-Dicke gravity from accumulated gravitational wave observations of merging black hole and neutron star.

    ↳ gr-qchep-ph1 citation
28. 28*

    Comment on "Gravitational Pair Production and Black Hole Evaporation"

    Antonio Ferreiro🇳🇱 · Jose Navarro-Salas🇪🇸 · Silvia Pla🇬🇧

    We scrutinize the recent Letter "Gravitational pair production and black hole evaporation" by M.F. Wondrak, W.D. van Suijlekom and H. Falcke [Phys. Rev. Lett. 130, 221502 (2023); arXiv:2305.18521]. We show that some consequences based on the proposed imaginary part of the lowest order effective action are in sharp tension with exact results on pair creation in electrodynamics and cosmology. This casts serious doubt on their claims for particle production in a Schwarzschild spacetime.

    ↳ gr-qchep-phhep-thPRL(2024)·14 citations
29. 29*

    Born-Infeld nonlinear electromagnetism in relativistic heavy ion collisions

    Will Price🇺🇸 · Martin Formanek🇨🇿 · Johann Rafelski🇺🇸

    We study the effect of the limiting field strength of Born-Infeld electromagnetism on the dynamics of charged particle scattering. We formulate the Born-Infeld limiting field in an invariant manner, showing that it is the electric field-dominated eigenvalue `$a$' of the field tensor $F^{\mu \nu }$ which is limited rather than the individual field vectors. Heavy ion collisions in particular provide uniquely large values of the field invariants that appear in the BI action, amplifying nonlinear effects. Thus ``$a$'' is the dominant input into the force between heavy ions that we use to compute the scattering angle as a function of impact parameter. We evaluate the BI effects, showing relevance at small impact parameters and exhibiting their dependence on the value of the limiting field strength.

    ↳ nucl-thhep-phquant-phActa Phys.Polon.A(2023)·3 citations
30. 30*

    Do the Early Galaxies observed by JWST disagree with Planck's CMB polarization measurements?

    Matteo Forconi🇮🇹 · Ruchika🇮🇹 · Alessandro Melchiorri🇮🇹 · Olga Mena🇪🇸 · Nicola Menci🇮🇹

    The recent observations from the James Webb Space Telescope have led to a surprising discovery of a significant density of massive galaxies with masses of $M\ge 10^{10.5}{M}_{\odot }$ at redshifts of approximately $z\sim 10$. This corresponds to a stellar mass density of roughly ${\rho }_{\ast }\sim 10^6{M}_{\odot }Mp{c}^{-3}$. Despite making conservative assumptions regarding galaxy formation, this finding may not be compatible with the standard $\Lambda$CDM cosmology that is favored by observations of CMB Anisotropies from the Planck satellite. In this paper, we confirm the substantial discrepancy with Planck's results within the $\Lambda$CDM framework. Assuming a value of $ϵ=0.2$ for the efficiency of converting baryons into stars, we indeed find that the $\Lambda$CDM model is excluded at more than $99.7\%$ confidence level (C.L.). An even more significant exclusion is found for $ϵ\sim 0.1$, while a better agreement, but still in tension at more than $95\%$, is obtained for $ϵ=0.32$. This tension, as already discussed in the literature, could arise either from systematics in the JWST measurements or from new physics. Here, as a last-ditch effort, we point out that disregarding the large angular scale polarization obtained by Planck, which allows for significantly larger values of the matter clustering parameter ${\sigma }_8$, could lead to better agreement between Planck and JWST within the $\Lambda$CDM framework. Interestingly, the model compatible with Planck temperature-only data and JWST observation also favors a higher Hubble constant $H_0=69.0\pm 1.1$ km/s/Mpc at $68\%$ C.L., in better agreement with observations based on SN-Ia luminosity distances.

    ↳ astro-ph.COhep-phJCAP(2023)·32 citations
31. 31*

    Old Data, New Forensics: The First Second of SN 1987A Neutrino Emission

    Shirley Weishi Li🇺🇸 · John F. Beacom🇺🇸 · Luke F. Roberts🇺🇸 · Francesco Capozzi🇮🇹

    The next Milky Way supernova will be an epochal event in multi-messenger astronomy, critical to tests of supernovae, neutrinos, and new physics. Realizing this potential depends on having realistic simulations of core collapse. We investigate the neutrino predictions of nearly all modern models (1-, 2-, and 3-d) over the first $\simeq$1 s, making the first detailed comparisons of these models to each other and to the SN 1987A neutrino data. Even with different methods and inputs, the models generally agree with each other. However, even considering the low neutrino counts, the models generally disagree with data. What can cause this? We show that neither neutrino oscillations nor different progenitor masses appear to be a sufficient solution. We outline urgently needed work.

    ↳ astro-ph.HEhep-phPRD(2024)·35 citations
32. 32*

    Regularization Scheme Dependence of the Counterterms in the Galaxy Bias Expansion

    Samuel Patrone🇺🇸 · Adriano Testa🇺🇸 · Mark B. Wise🇺🇸

    In this paper we explore how different regularization prescriptions affect the counterterms in the renormalization of the galaxy bias expansion. We work in the context of primordial local non-Gaussianity including non-linear gravitational evolution. We carry out the one-loop renormalization of the field ${\delta }_{\rho }^2$ (i.e. the square of the matter overdensity field) up to third order in gravitational evolution. Three regularization schemes are considered and their impact on the values of the counterterms is studied. We explicitly verify that the coefficients of the non-boost invariant operators are regularization scheme independent.

    ↳ astro-ph.COhep-phJCAP(2023)·5 citations
33. 33*

    The impact of baryonic potentials on the gravothermal evolution of self-interacting dark matter haloes

    Yi-Ming Zhong🇺🇸 · Daneng Yang🇺🇸 · Hai-Bo Yu🇺🇸

    The presence of a central baryonic potential can have a significant impact on the gravothermal evolution of self-interacting dark matter (SIDM) haloes. We extend a semi-analytical fluid model to incorporate the influence of a static baryonic potential and calibrate it using controlled N-body simulations. We construct benchmark scenarios with varying baryon concentrations and different SIDM models, including constant and velocity-dependent self-interacting cross sections. The presence of the baryonic potential induces changes in SIDM halo properties, including central density, core size, and velocity dispersion, and it accelerates the halo's evolution in both expansion and collapse phases. Furthermore, we observe a quasi-universality in the gravothermal evolution of SIDM haloes with the baryonic potential, resembling a previously known feature in the absence of the baryons. By appropriately rescaling the physical quantities that characterize the SIDM haloes, the evolution of all our benchmark cases exhibits remarkable similarity. Our findings offer a framework for testing SIDM predictions using observations of galactic systems where baryons play a significant dynamical role.

    ↳ astro-ph.COastro-ph.GAhep-phMNRAS(2023)·58 citations
34. 34*

    Strong Interaction Physics at the Luminosity Frontier with 22 GeV Electrons at Jefferson Lab

    A. Accardi🇺🇸 · P. Achenbach🇺🇸 · D. Adhikari🇺🇸 · A. Afanasev🇺🇸 · C.S. Akondi🇺🇸 · N. Akopov🇦🇲 · M. Albaladejo🇪🇸 · H. Albataineh🇺🇸 · M. Albrecht🇺🇸 · B. Almeida-Zamora🇲🇽 · M. Amaryan🇺🇸 · D. Androić🇭🇷 and 432 other authors

    This document presents the initial scientific case for upgrading the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (JLab) to 22 GeV. It is the result of a community effort, incorporating insights from a series of workshops conducted between March 2022 and April 2023. With a track record of over 25 years in delivering the world's most intense and precise multi-GeV electron beams, CEBAF's potential for a higher energy upgrade presents a unique opportunity for an innovative nuclear physics program, which seamlessly integrates a rich historical background with a promising future. The proposed physics program encompass a diverse range of investigations centered around the nonperturbative dynamics inherent in hadron structure and the exploration of strongly interacting systems. It builds upon the exceptional capabilities of CEBAF in high-luminosity operations, the availability of existing or planned Hall equipment, and recent advancements in accelerator technology. The proposed program cover various scientific topics, including Hadron Spectroscopy, Partonic Structure and Spin, Hadronization and Transverse Momentum, Spatial Structure, Mechanical Properties, Form Factors and Emergent Hadron Mass, Hadron-Quark Transition, and Nuclear Dynamics at Extreme Conditions, as well as QCD Confinement and Fundamental Symmetries. Each topic highlights the key measurements achievable at a 22 GeV CEBAF accelerator. Furthermore, this document outlines the significant physics outcomes and unique aspects of these programs that distinguish them from other existing or planned facilities. In summary, this document provides an exciting rationale for the energy upgrade of CEBAF to 22 GeV, outlining the transformative scientific potential that lies within reach, and the remarkable opportunities it offers for advancing our understanding of hadron physics and related fundamental phenomena.

    ↳ nucl-exhep-exhep-phnucl-thEPJA(2024)·225 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.