Tue·Jun 21, 2022Tuesday·June 21, 2022

1. 01*

   Gluon mass from charmonium radiative decay and its impact on the hybrid meson properties

   Azzeddine Benhamida🇩🇿 · Lahouari Semlala🇩🇿

   We study the photon spectrum in the radiative decays of the charmonium $\frac{1}{\Gamma }\frac{d\Gamma (J/\psi \to \gamma gg)}{dz}$ as an excellent scene for hunting the exotic mesons (hybrids $q\bar{q}g$ and glueballs $gg$) and an ideal frame for the theoretical and phenomenological investigations of the gluon nature in IR, by subtle estimation of its non-zero effective mass which seems required in Quark-Gluon Constituent Model (QGCM) for identifying the nature of these exotic species.

   hep-phphysics.soc-ph1 citation
2. 02*

   Exploring Parameter Spaces with Artificial Intelligence and Machine Learning Black-Box Optimisation Algorithms

   Fernando Abreu de Souza🇵🇹 · Miguel Crispim Romão🇵🇹 · Nuno Filipe Castro🇵🇹 · Mehraveh Nikjoo🇵🇹 · Werner Porod🇩🇪

   Constraining Beyond the Standard Model theories usually involves scanning highly multi-dimensional parameter spaces and check observable predictions against experimental bounds and theoretical constraints. Such task is often timely and computationally expensive, especially when the model is severely constrained and thus leading to very low random sampling efficiency. In this work we tackled this challenge using Artificial Intelligence and Machine Learning search algorithms used for Black-Box optimisation problems. Using the cMSSM and the pMSSM parameter spaces, we consider both the Higgs mass and the Dark Matter Relic Density constraints to study their sampling efficiency and parameter space coverage. We find our methodology to produce orders of magnitude improvement of sampling efficiency whilst reasonably covering the parameter space.

   hep-phphysics.comp-phphysics.data-anPRD(2023)·28 citations
3. 03*

   Self-consistency in models of neutrino scattering and fast flavor conversion

   Lucas Johns🇺🇸 · Hiroki Nagakura🇯🇵

   Several recent numerical studies have examined the effects of neutrino neutral-current scattering on fast flavor conversion (FFC). Those studies are in apparent conflict, with some finding enhancement of flavor conversion and others finding suppression. The ones that report enhancement all use homogeneous models, and we discuss in detail the self-consistency issues that they face as a result. We reproduce scattering-enhanced FFC in our own homogeneous calculations, showing that it occurs for both neutral- and charged-current scattering and that it is due to isotropization of the angular distributions over time. Because this is the very feature of the calculations that is not self-consistent, we conclude that the enhancement effect is of unclear astrophysical relevance and may not occur in natural environments.

   hep-phastro-ph.HEPRD(2022)·24 citations
4. 04*

   Neutrino-anti-neutrino instability in dense neutrino systems, with applications to the early universe and to supernovae

   R. F. Sawyer🇺🇸

   We exhibit a new instability that leads to "fast" coherent neutrino-antineutrino mixing in a dense neutrino cloud, arising from the standard four-Fermi interaction induced by Z exchange, and overlooked in the big existing literature on fast processes in this venue. It can play an essential role in creation of an abundance of pseudoscalar mesons of mass in the KeV range in the early universe, at temperatures in the range 10-100 MeV. Also it can overpower existing calculations in the "neutrino bulb" regions of the supernova cloud.

   hep-ph7 citations
5. 05*

   Studying triangle singularity through spin observables

   Ke Wang🇨🇳 · Shao-Fei Chen🇨🇳 · Bo-Chao Liu🇨🇳

   In this work, we study the spin density matrix element ${\rho }_{00}$ of the $\varphi$ in the decay $J/\psi \to \eta \pi \varphi$. In previous studies, a band around 1.4 GeV on the ${\pi }^0\varphi$ distribution in Dalitz plot was reported by the BESIII Collaboration. This structure may be caused by the production of a resonance or the triangle singularity mechanism. We find that the predictions of the spin density matrix elements of the final $\varphi$ based on these mechanisms show distinct features. Thus the measurement of the spin density matrix elements of the $\varphi$ in this reaction may offer an alternative way to study the triangle singularity and to clarify the reaction mechanisms, i.e. resonance production or kinematic effects. This work also shows the potential of spin observables in studying kinematic singularities.

   hep-phhep-exPRD(2022)·7 citations
6. 06*

   Nucleon form factors and parton distributions in nonlocal chiral effective theory

   P. Wang🇨🇳 · Fangcheng He🇨🇳 · Chueng-Ryong Ji🇺🇸 · W. Melnitchouk🇺🇸

   We present a review of recent applications of nonlocal chiral effective theory to hadron structure studies. Starting from a nonlocal meson--baryon effective chiral Lagrangian, we show how the introduction of a correlation function representing the finite extent of hadrons regularizes the meson loop integrals and introduces momentum dependence in vertex form factors in a gauge invariant manner. We apply the framework to the calculation of nucleon electromagnetic form factors, unpolarized and polarized parton distributions, as well as transverse momentum dependent distributions and generalized parton distributions. Assuming that the nonlocal behavior is a general property of all interactions, we also discuss the application to the lepton anomalous magnetic moment in nonlocal QED.

   hep-phhep-exhep-latnucl-thPPNP(2023)·14 citations
7. 07*

   The high-energy spectrum of QCD from inclusive emissions of charmed $B$-mesons

   Francesco Giovanni Celiberto🇮🇹

   We investigate the high-energy behavior of strong interactions through a study on the inclusive hadroproduction of charmed $B$-mesons ($B_c$ or $B_c^{\ast }$ states) accompanied by non-charmed $b$-hadron or light-flavored jet emissions at LHC energies and kinematic configurations. By making use of the hybrid high-energy and collinear factorization, where the standard fixed-order description based on collinear parton densities and fragmentation functions is enhanced via the Balitsky-Fadin-Kuraev-Lipatov (BFKL) resummation of energy logarithms, we perform a full next-to-leading order analysis of distributions differential in rapidities and azimuthal angles calculated by the hands of the JETHAD multi-modular working package. The large observed transverse momenta justify the use of non-relativistic QCD next-to-leading order fragmentation functions to describe the heavy-flavored meson production mechanism. We come out with the conclusion that the study of this process can be included in forthcoming analyses at the (high-luminosity) LHC as a tool to access the QCD dynamics at high energies and to explore possible common ground between different resummation approaches.

   hep-phhep-exPLB(2022)·56 citations
8. 08*

   Effects of electroweak radiative corrections in polarized low-energy electron-positron annihilation into lepton pairs

   A.Arbuzov (1)🇷🇺 · S.Bondarenko (1)🇷🇺 · Ya.Dydyshka (2,3)🇷🇺 · L.Kalinovskaya (2)🇷🇺 · L.Rumyantsev (2)🇷🇺 · R.Sadykov (2)🇷🇺 · V.Yermolchyk (2,3)🇷🇺 · U.Yermolchyk (2,3) ((1) Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna, Moscow region, Russia, (2) Dzhelepov Laboratory of Nuclear Problems, JINR, 141980 Dubna, Moscow region, Russia, (3) Institute for Nuclear Problems, Belarusian State University, Minsk, 220006 Belarus)🇷🇺

   Complete one-loop electroweak radiative corrections to the cross section of the process $e^{+}{e}^{-}\to {\mu }^{-}{\mu }^{+}({\tau }^{-}{\tau }^{+})$ are evaluated with the help of the \SANC system. Higher-order contributions of the initial state radiation are computed in the QED structure function formalism. Numerical results are given for the center-of-mass energy range $\sqrt{s}=5,7$~GeV for various polarization degrees of the initial particles.

   hep-phJETP Lett.(2022)·5 citations
9. 09*

   Highly excited and exotic fully-strange tetraquark states

   Rui-Rui Dong🇨🇳 · Niu Su🇨🇳 · Hua-Xing Chen🇨🇳

   Some hadrons have the exotic quantum numbers that the traditional $\bar{q}q$ mesons and $qqq$ baryons can not reach, such as $J^{PC}=0^{--}/0^{+-}/1^{-+}/2^{+-}/3^{-+}/4^{+-}$, etc. We investigate for the first time the exotic quantum number $J^{PC}=4^{+-}$, and study the fully-strange tetraquark states with such an exotic quantum number. We systematically construct all the diquark-antidiquark interpolating currents, and apply the method of QCD sum rules to calculate both the diagonal and off-diagonal correlation functions. The obtained results are used to construct three mixing currents that are nearly non-correlated, and we use one of them to extract the mass of the lowest-lying state to be $2.85_{-0.22}^{+0.19}$ GeV. We apply the Fierz rearrangement to transform this mixing current to be the combination of three meson-meson currents, and the obtained Fierz identity suggests that this state dominantly decays into the $P$-wave $\varphi (1020)f_2^{\prime }(1525)$ channel. This fully-strange tetraquark state of $J^{PC}=4^{+-}$ is a purely exotic hadron to be potentially observed in future particle experiments.

   hep-phhep-exhep-latEPJC(2022)·14 citations
10. 10*

    P-even, CP-violating Signals in Scalar-Mediated Processes

    Howard E. Haber🇺🇸 · Venus Keus🇮🇪 · Rui Santos🇵🇹

    Most studies of Higgs sector CP violation focus on the detection of CP-violating neutral Higgs-fermion Yukawa couplings, which yield P-odd, CP-violating phenomena. There is some literature on purely bosonic signatures of Higgs sector CP violation, where the simultaneous observation of three processes (suitably chosen) constitutes a signal of P-even CP violation. However, in the examples previously analyzed, some of the processes are strongly suppressed in the approximate Higgs alignment limit (corresponding to the existence of a Standard Model like Higgs boson as suggested by LHC data), in which case the proposed CP-violating signals are difficult to observe in practice. In this paper, we extend the existing literature by examining processes that do not vanish in the Higgs alignment limit and whose simultaneous observation would provide unambiguous evidence for scalar-mediated P-even CP violation. We assess the discovery potential of such signals at various future multi-TeV lepton (and $\gamma \gamma$) colliders. The potential for detecting loop-induced P-even, CP-violating phenomena is also considered.

    hep-phPRD(2022)·19 citations
11. 11*

    Neutrinoless double beta decay and the muonium-to-antimuonium transition in models with a doubly charged scalar

    Takeshi Fukuyama🇯🇵 · Yukihiro Mimura🇯🇵 · Yuichi Uesaka🇯🇵

    The lepton number and flavor violations are important possible ingredients of the lepton physics. The neutrinoless double beta decay and the transition of the muonium into antimuonuim are related to those violations. The former can give us an essential part of fundamental physics, and there are plenty of experimental attempts to observe the process. The latter has also been one of the attractive phenomena, and the experimental bound will be updated in planned experiments at new high-intensity muon beamlines. In models with a doubly charged scalar, not only can those two processes be induced, but also the active neutrino masses can be induced radiatively. The flavor violating decays of the charged leptons constrain the flavor parameters of the models. We study how the muonium-to-antimuonium transition rate can be as large as the current experimental bound, and we insist that the updated bound of the transition rate will be useful to distinguish the models to generate the neutrinoless double beta decay via the doubly charged scalar. We also study a possible extension of the model to the left-right model which can induce the neutrinoless double beta decay.

    hep-phPRD(2022)·6 citations
12. 12*

    On a model with two scalar leptoquarks -- $R_2$ and $S_3$

    Damir Bečirević🇫🇷 · Ilja Doršner🇭🇷 · Svjetlana Fajfer🇸🇮 · Darius A. Faroughy🇨🇭 · Florentin Jaffredo🇫🇷 · Nejc Košnik🇸🇮 · Olcyr Sumensari🇫🇷

    We discuss a model that can accommodate the $B$-physics anomalies, based on combining two scalar leptoquarks, $R_2$ and $S_3$, of mass $\mathcal{O}(1\mathrm{TeV})$, and that we proposed in our previous paper. We update the analysis of its parameter space and show that a model remains viable and consistent with a number of low energy and high energy flavor physics constraints. Since the model predicts a non-zero New Physics phase, we discuss the possibility to test its contribution to the neutron electric dipole moment and to the angular distributions of the exclusive $b\to c\tau \bar{\nu }$ decays. We find that the model can provide a significant enhancement to $\mathcal{B}(B\to K^{(\ast )}\nu \nu )$ and provides both the upper and lower bounds to $\mathcal{B}(B\to K^{(\ast )}\mu \tau )$.

    hep-phhep-exhep-latPRD(2022)·29 citations
13. 13*

    Neutrino mass square ratio and neutrinoless double beta decay in random neutrino mass matrices

    Naoyuki Haba🇯🇵 · Yasuhiro Shimizu🇯🇵 · Toshifumi Yamada🇯🇵

    We study the neutrino mass anarchy in the Dirac neutrino, seesaw, double seesaw models. Assuming the anarchy hypothesis, the mass matrices are random and distributed in accordance with the Gaussian measure. We focus on the distributions of mass square ratio of the light neutrinos and examine which of these models shows a peak in the probability distribution around the experimental value. We show that the peak position depends on the number of random matrix products. We find that the light neutrino mass hierarchy becomes larger as the number of random matrix products is increased and the seesaw model with the random Dirac and Majorana mass matrices is the most probable to realize the current experimental data. We also investigate the distributions of the effective Majorana mass for neutrinoless double beta decay. We find that the effective Majorana mass is smaller than the experimental upper bound and tends to be smaller as the number of random matrix products increases because the light neutrino masses become more hierarchical. We argue that the tendency for lighter neutrino masses to become more hierarchical as the number of products in the random matrix increases can be understood from the probability distribution of singular values in random matrix theory.

    hep-phPTEP(2023)·4 citations
14. 14*

    Leptoquarks, axions and the unification of B, L, and Peccei-Quinn symmetries

    Fernando Arias-Aragón🇫🇷 · Christopher Smith🇫🇷

    In this paper, axion models supplemented by leptoquarks and diquarks are systematically analyzed. Turning on some couplings to and among these latter states permits to unify the Peccei-Quinn symmetry with baryon (B) and lepton (L) numbers, such that the axion becomes associated to the spontaneous breaking of the three $U(1)$ symmetries. All possible four- and six-fermion patterns of B and L violation are discussed, including those inducing proton decay, with $\Delta B=1$ and $\Delta L=\pm 1,\pm 3$, neutron-antineutron oscillations with $\Delta B=2$, and Majorana neutrino masses with $\Delta L=2$. Scenarios in which one or two axion fields necessarily appear in any B and/or L violating operators are also constructed. Nucleon decays would then necessarily involve an axion in the final state, while neutron-antineutron oscillations would only happen in an axionic background. This could have implications for the neutron lifetime puzzle, and more generally, opens the door to new phenomenological and cosmological applications.

    hep-phPRD(2022)·15 citations
15. 15*

    Kinetic Mixing, Dark Higgs Triplets, $M_W$ and All That

    Thomas G. Rizzo🇺🇸

    The kinetic mixing (KM) portal is a popular mechanism which allows light dark matter (DM) in the mass range below $\sim 1$ GeV to achieve the observed relic density by thermal means and can be effectively described by only a few parameters, e.g., $ϵ$, the strength of this KM. In the simplest setup, the Standard Model (SM) $U(1{)}_Y$ hypercharge gauge boson and a $U(1{)}_D$ dark photon (DP), which only couples to fields in the dark sector, experience KM via loops of portal matter (PM) fields which have both SM and dark charges thus generating a small coupling between us and dark matter (DM). However, if one wishes to understand the underlying physics behind this idea in a deeper fashion we need to take a step upward to a more UV-complete picture. Meanwhile, CDFII has measured a value for the $W$-boson mass which lies significantly above SM expectations. In this paper we speculate that this shift in the $W$'s mass may be related to the $\sim 1$ GeV mass of the DP within a framework of scalar PM that leads to phenomenologically interesting values of $ϵ$ via non-abelian KM due to the existence of an $SU(2{)}_L$, $Y=0$, {\it complex} Higgs triplet which carries a non-zero value of the $U(1{)}_D$ dark charge. Possible gauge boson plus missing energy signatures of this scenario that can appear at the LHC and elsewhere are examined. Indeed, with modest assumptions, all of the new scalar PM states are predicted to have masses below roughly $\simeq 630$ GeV and so should be at least kinematically accessible. The HL-LHC will very likely to be able to explore all of this model's allowed parameter space.

    hep-phPRD(2022)·36 citations
16. 16*

    Reheating constraints on modified single-field Natural Inflation models

    Hua Zhou🇨🇳 · Qing Yu🇨🇳 · Yu Pan🇨🇳 · Ruiyu Zhou🇨🇳 · Wei Cheng🇨🇳

    In this paper, we discuss three modified single-field natural inflation models in detail, including Special generalized Natural Inflation model(SNI), Extended Natural Inflation model(ENI) and Natural Inflation inspired model(NII). We derive the analytical expression of the tensor-to-scalar ratio $r$ and the spectral index $n_s$ for those models. Then the reheating temperature $T_{re}$ and reheating duration $N_{re}$ are analytically derived. Moreover, considering the CMB constraints, the feasible space of the SNI model in $(n_s,r)$ plane is almost covered by that of the NII, which means the NII is more general than the SNI. In addition, there is no overlapping space between the ENI and the other two models in $(n_s,r)$ plane, which indicates that the ENI and the other two models exclude each other, and more accurate experiments can verify them. Furthermore, the reheating brings tighter constraints to the inflation models, but they still work for a different reheating universe. Considering the constraints of $n_s$, $r$, $N_k$ and choosing $T_{re}$ near the electroweak energy scale, one can find that the decay constants of the three models have no overlapping area and the effective equations of state ${\omega }_{re}$ should be within $\frac{1}{4}\lesssim {\omega }_{re}\lesssim \frac{4}{5}$ for the three models.

    hep-phEPJC(2022)·15 citations
17. 17*

    Neutrino Detection without Neutrino Detectors: Discovering Collider Neutrinos at FASER with Electronic Signals Only

    Jason Arakawa🇺🇸 · Jonathan L. Feng🇺🇸 · Ahmed Ismail🇺🇸 · Felix Kling🇩🇪 · Michael Waterbury🇮🇱

    The detection of collider neutrinos will provide new insights about neutrino production, propagation, and interactions at TeV energies, the highest human-made energies ever observed. During Run 3 of the LHC, the FASER experiment is expected to detect roughly $10^4$ collider neutrinos using its emulsion-based neutrino detector FASER$\nu$. In this study, we show that, even without processing the emulsion data, low-level input provided by the electronic detector components of FASER and FASER$\nu$ will be able to establish a $5\sigma$ discovery of collider neutrinos with as little as $5{\text{fb}}^{-1}$ of integrated luminosity. These results foreshadow the possible early discovery of collider neutrinos in LHC Run 3.

    hep-phphysics.ins-detPRD(2022)·16 citations
18. 18*

    High Energy Physics activities in Africa: An overview

    Yasmine Amhis🇫🇷 · Mohamed Chabab🇲🇦 · Zinhle Buthelzi🇿🇦

    This document summarizes our best knowledge of the ongoing High Energy Physics activities in Africa. The information was primarily extracted from the first ASFAP Particle Physics day organised on November 2021 and on our working group talk presented at ACP 2021 conference on March 2022.

    hep-phphysics.soc-ph1 citation
19. 19*

    Score-based Generative Models for Calorimeter Shower Simulation

    Vinicius Mikuni🇺🇸 · Benjamin Nachman🇺🇸

    Score-based generative models are a new class of generative algorithms that have been shown to produce realistic images even in high dimensional spaces, currently surpassing other state-of-the-art models for different benchmark categories and applications. In this work we introduce CaloScore, a score-based generative model for collider physics applied to calorimeter shower generation. Three different diffusion models are investigated using the Fast Calorimeter Simulation Challenge 2022 dataset. CaloScore is the first application of a score-based generative model in collider physics and is able to produce high-fidelity calorimeter images for all datasets, providing an alternative paradigm for calorimeter shower simulation.

    hep-phcs.LGhep-exphysics.data-an+1PRD(2022)·125 citations
20. 20*

    Analytical calculations of the Quantum Tsallis thermodynamic variables

    Ayman Hussein🇪🇬 · Trambak Bhattacharyya🇷🇺

    In this article, we provide an account of analytical results related to the Tsallis thermodynamics that have been the subject matter of a lot of studies in the field of high-energy collisions. After reviewing the results for the classical case in the massless limit and for arbitrarily massive classical particles, we compute the quantum thermodynamic variables. For the first time, the analytical formula for the pressure of a Tsallis-like gas of massive bosons has been obtained. Hence, this article serves both as a brief review of the knowledge gathered in this area, and as an original research that forwards the existing scholarship. The results of the present paper will be important in a plethora of studies in the field of high-energy collisions including the propagation of non-linear waves generated by the traversal of high-energy particles inside the quark-gluon plasma medium showing the features of non-extensivity.

    ↳ cond-mat.stat-mechhep-phhep-thnucl-thMDPI Physics(2022)·1 citation
21. 21*

    Strange quark matter from a baryonic approach

    Eduardo S. Fraga🇧🇷 · Rodrigo da Mata🇧🇷 · Savvas Pitsinigkos🇬🇧 · Andreas Schmitt🇬🇧

    We construct a model for dense matter based on low-density nuclear matter properties that exhibits a chiral phase transition and that includes strangeness through hyperonic degrees of freedom. Empirical constraints from nuclear matter alone allow for various scenarios, from a strong first-order chiral transition at relatively low densities through a weaker transition at higher densities, even up to a smooth crossover not far beyond the edge of the allowed range. The model parameters can be chosen such that at asymptotically large densities the chirally restored phase contains strangeness and the speed of sound approaches the conformal limit, resulting in a high-density phase that resembles deconfined quark matter. Additionally, if the model is required to reproduce sufficiently massive compact stars, the allowed parameter range is significantly narrowed down, resulting for instance in a very narrow range for the poorly known slope parameter of the symmetry energy, $L\simeq (88-92)\mathrm{MeV}$. We also find that for the allowed parameter range strangeness does not appear in the form of hyperons in the chirally broken phase and the chiral transition is of first order. Due to its unified approach and relative simplicity - here we restrict ourselves to zero temperature and the mean-field approximation - the model can be used in the future to study dense matter under compact star conditions in the vicinity of the chiral phase transition, for instance to compute the surface tension or to investigate spatially inhomogeneous phases.

    ↳ nucl-thastro-ph.HEhep-phPRD(2022)·15 citations
22. 22*

    Non-radial oscillations and global stellar properties of anisotropic compact stars using realistic equations of state

    Elvis J. Aquino Curi · Luis B. Castro🇧🇷 · Cesar V. Flores🇧🇷 · César H. Lenzi🇧🇷

    In this work, we have made a systematic study of how the gravitational wave frequency of the fundamental mode from compact stars is affected by anisotropic effects using realistic equations of state. Our study is an extension of the seminal research performed by Doneva [Phys. Rev. D 85 (2012) 124023], where a polytropic equation of state was used. To achieve our objective, we considered compact stars which were built by using equations of state in the framework of a relativistic mean field theory for the case of hadronic stars and in the framework of the MIT model for the case of quark stars. In order to obtain some pertinent information that could give us the possibility to detect the anisotropy in compact stars, we also studied and analized the behaviour of various global stellar quantities, e.g., gravitational redshift, stellar mass, radius, among others. We concluded that the anisotropic effects can have important consequences, which are strongly related to the anisotropic parameter and the equation of state of high density matter. Additionally, a comparison with observational data has been made and we have shown that the anisotropic parameter $\lambda$ can be used as a tuning parameter to reproduce mass and radius observational data of neutron stars.

    ↳ gr-qcastro-ph.HEastro-ph.SRhep-ph+1EPJC(2022)·37 citations
23. 23*

    Lattice Monte Carlo Simulations with Two Impurity Worldlines

    Fabian Hildenbrand🇩🇪 · Serdar Elhatisari🇹🇷 · Timo A. Lähde🇩🇪 · Dean Lee🇺🇸 · Ulf-G. Meißner🇩🇪

    We develop the impurity lattice Monte Carlo formalism, for the case of two distinguishable impurities in a bath of polarized fermions. The majority particles are treated as explicit degrees of freedom, while the impurities are described by worldlines. The latter serve as localized auxiliary fields, which affect the majority particles. We apply the method to non-relativistic three-dimensional systems of two impurities and a number of majority particles where both the impurity-impurity interaction and the impurity-majority interaction have zero range. We consider the case of an attractive impurity-majority interaction, and we study the formation and disintegration of bound states as a function of the impurity-impurity interaction strength. We also discuss the potential applications of this formalism to other quantum many-body systems.

    ↳ nucl-thhep-lathep-phphysics.comp-phEPJA(2022)·10 citations
24. 24*

    Equation of state of fermions in neutron stars

    Samina Masood🇺🇸 · Serkan Caliskan🇺🇸

    Employing both the number density and energy density, the equation of state of fermions for each microscopic region of a neutron star is derived in the presence of various statistical effects. It is computed as functions of temperature (T), chemical potential (\mu) and magnetic field (B) based on the statistical properties and corresponding phases of neutron stars. It is revealed that the measurable properties describing the dynamic behavior of a neutron star are determined by the unusual statistical conditions. It is demonstrated that, in a strong magnetic field (B larger than\mu), the pressure (P) shows a logarithmic dependence on B (P is proportional to logarithm of(\mu/B). It is found that the regions with a higher (lower) magnetic field (density) have a shorter (longer) life time. Moreover, the relationship between the magnetic field and chemical potential confirms that the large magnetic field and high density are short lived as compared to low magnetic field and low density at the same temperature.

    ↳ astro-ph.HEhep-ph0 citations
25. 25*

    Rebalance and Smear for Multi-jet Background Estimation

    Samuel Bein (Universität Hamburg)🇩🇪 · Christian Sander (Deutsches Elektronen-Synchrotron DESY)🇩🇪

    For many particle collider searches for physics beyond the Standard Model in final states with jets and missing transverse momentum, events from QCD multi-jet processes are an important and challenging background contribution. The CMS and ATLAS experiments have previously developed data-driven methods designed to succeed where Monte Carlo methods suffer large theoretical and experimental uncertainties. One such method is Rebalance and Smear (R&S), which predicts QCD backgrounds by applying a series of folding and unfolding techniques to data control regions. A top-to-bottom description of the R&S method is presented, along with a discussion of its applicability and limitations. A software application is provided that performs the R\&S method using public, non-proprietary tools, interfacing with data sets produced by Delphes3. In general, the method is suitable for predicting multi-jet backgrounds in searches for stable non-detectable particles, such as dark matter candidates. A case study is carried out in simulated events of proton-proton collisions at 14 TeV in the context of a potential search for Higgsino dark matter produced in the decay products of supersymmetric quark partners. Sources of potential bias are explored and prescriptions for evaluating systematic uncertainties are suggested.

    ↳ hep-exhep-phJINST(2022)·1 citation
26. 26*

    Detailed analysis of the curvature bounce: background dynamics and imprints in the CMB

    Cyril Renevey🇫🇷 · Aurélien Barrau🇫🇷 · Killian Martineau🇫🇷

    If the spatial sections of the Universe are positively curved, extrapolating the inflationary stage backward in time inevitably leads to a classical bounce. This simple scenario, non-singular and free of exotic physics, deserves to be investigated in details. The background dynamics exhibits interesting features and is shown to be mostly insensitive to initial conditions as long as observational consequences are considered. The primordial scalar power spectrum is explicitly computed, for different inflaton potentials, and the subsequent CMB temperature anisotropies are calculated. The results are compatible with current measurements. Some deviations with respect to the standard paradigm can however appear at large scales and we carefully disentangle what is associated with the vacuum choice with what is more fundamentally due to the bounce itself.

    ↳ gr-qcastro-ph.COhep-phEPJC(2022)·5 citations
27. 27*

    One-loop fixed points of adjoint multi-scalar gauge theory in four dimensions

    Nadia Flodgren🇸🇪 · Bo Sundborg🇸🇪

    We determine complete one-loop beta functions of the multi-scalar four-point couplings in four-dimensional $SU(N)$ gauge theories with $M$ adjoint scalar multiplets. For adjoints scalars, the sign of the one loop gauge coupling beta function depends solely on $M$, vanishing and changing sign precisely at $M=22$. For the multi-scalar potential at fixed gauge coupling we find several fixed points with different stability properties at large $N$. The analysis crucially involves the full set of four $SU(N)$ and $O(M)$ invariant single trace and double trace couplings. Taking the gauge coupling into account, there are asymptotically free RG flows for $M<22$ and non-trivial fixed points for $M=22$ at one loop, while $M>22$ appears to ruin the UV properties of the theory. Surprisingly, uniquely between $M=22$ and $M=21$ the number of fixed flows drops from eight to four in the large $N$ limit. There seems to be something very special about $M=22$. More speculatively, the $M=22$ one-loop conformal fixed point theory with $M$ adjoint scalars in $d=4$ suggests the possibility of an isolated non-supersymmetric, purely bosonic AdS${}_{4+1}\times$S${}^{22-1}$/CFT${}_4$ correspondence. Our example suggests that extending the potential to the complete set of terms allowed by symmetries may lead to real fixed points also in non-supersymmetric theories descending from $\mathcal{N}=4$ super-Yang-Mills theory.

    ↳ hep-thhep-ph0 citations
28. 28*

    First-order phase transition and fate of false vacuum remnants

    Kiyoharu Kawana🇰🇷 · Philip Lu🇰🇷 · Ke-Pan Xie🇺🇸

    False vacuum remnants in first-order phase transitions in the early Universe can form compact objects which may constitute dark matter. Such remnants form because particles develop large mass gaps between the two phases and become trapped in the old phase. We focus on remnants generated in a class of models with trapped dark sector particles, trace their development, and determine their ultimate fate. Depending on model and phase transition parameters, the evolutionary endpoint of these remnants can be primordial black holes, Fermi-balls, Q-balls, or thermal balls, and they all have the potential to constitute some portion or the whole of dark matter within a broad mass range. Notably, dark sector thermal balls can remain at high temperatures until the present day and are a new compact dark matter candidate which derives its energy from the thermal energy of internal particles instead of their mass or quantum pressure.

    ↳ astro-ph.COhep-phJCAP(2022)·54 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.