Thu·Apr 8, 2021Thursday·April 8, 2021

1. 01*

   Neutrino collective effects during their decoupling era in the early universe

   Raymond F. Sawyer🇺🇸

   There is an accepted approach to calculation of the neutrino flavor density-matrix in the halo of a supernova, in which neutrino amplitudes, not cross-sections, need to be followed carefully in the region above the region of frequent scatterings. The same reasoning and techniques, applied to the evolution of neutrino flavors and energy distributions in the early universe in the era of neutrino decoupling, leads to radical changes in the predictions of the effects of the neutrino-neutrino interaction. Predictions for the production of sterile neutrinos, should they exist, will also be changed.

   hep-phastro-ph.CO5 citations
2. 02*

   Exploring the flavor content of light and heavy-light pseudoscalars

   R. M. Moita (Instituto Tecnológico de Aeronáutica, DCTA, São José dos Campos, Brazil)🇧🇷 · J. P. B. C. de Melo (Laboratório de Física Teórica e Computacional - LFTC - UCS/UNICID São Paulo, Brazil)🇧🇷 · K. Tsushima (Laboratório de Física Teórica e Computacional - LFTC - UCS/UNICID- São Paulo, Brazil)🇧🇷 · T. Frederico (Instituto Tecnológico de Aeronáutica, DCTA, São José dos Campos, Brazil)🇧🇷

   The electroweak properties of light and charmed D and Ds pseudoscalar mesons are investigated within a unified covariant constituent quark model. The quark-antiquark-meson vertices are assumed to have a symmetric form by the exchange of quark momenta, which is successful in describing the light pseudoscalar meson properties. The flavor decomposition of the elastic electromagnetic form factors, electromagnetic charge radii, and weak decay constants are calculated. Based on the results a discussion on the SU(3) and SU(4) symmetry breaking is made and a comparison with the pion and kaon properties to highlight the Higgs contribution to the structure of these mesons.

   hep-phnucl-thPRD(2021)·13 citations
3. 03*

   Electroweak and Left-Right Phase Transitions in $SO(5)\times U(1)\times SU(3)$ Gauge-Higgs Unification

   Shuichiro Funatsu🇨🇳 · Hisaki Hatanaka🇯🇵 · Yutaka Hosotani🇯🇵 · Yuta Orikasa🇨🇿 · Naoki Yamatsu🇯🇵

   The electroweak phase transition in GUT inspired $SO(5)\times U(1)\times SU(3)$ gauge-Higgs unification is shown to be weakly first order and occurs at $T=T_c^{\mathrm{EW}}\sim 163$GeV, which is very similar to the behavior in the standard model in perturbation theory. A new phase appears at higher temperatures. $SU(2{)}_L\times U(1{)}_Y$ (${\theta }_H=0$) and $SU(2{)}_R\times U(1{)}_{Y^{\prime }}$ (${\theta }_H=\pi$) phases become almost degenerate above $T\sim m_{\mathrm{KK}}$ where $m_{\mathrm{KK}}$ is the Kaluza-Klein mass scale typically around 13TeV and ${\theta }_H$ is the Aharonov-Bohm phase along the fifth dimension. The two phases become degenerate at $T=T_c^{\mathrm{LR}}\sim m_{\mathrm{KK}}$. As the temperature drops in the evolution of the early Universe the $SU(2{)}_R\times U(1{)}_{Y^{\prime }}$ phase becomes unstable. The tunneling rate from the $SU(2{)}_R\times U(1{)}_{Y^{\prime }}$ phase to the $SU(2{)}_L\times U(1{)}_Y$ phase becomes sizable and a first-order phase transition takes place at $T=2.5\sim 2.6$TeV. The amount of gravitational waves produced in this left-right phase transition is small, far below the reach of the sensitivity of Laser Interferometer Space Antenna (LISA). A detailed analysis of the $SU(2{)}_R\times U(1{)}_{Y^{\prime }}$ phase is also given. It is shown that the $W$ boson, $Z$ boson and photon, with ${\theta }_H$ varying from 0 to $\pi$, are transformed to gauge bosons in the $SU(2{)}_R\times U(1{)}_{Y^{\prime }}$ phase. Gauge couplings and wave functions of quarks, leptons and dark fermions in the $SU(2{)}_R\times U(1{)}_{Y^{\prime }}$ phase are determined.

   hep-phPRD(2021)·18 citations
4. 04*

   Topological interaction of neutrino with photon in the magnetic field -- Electroweak Hall effect

   Kenzo Ishikawa🇯🇵 · Yutaka Tobita🇯🇵

   The effective interaction of a neutrino with a photon in magnetized plasma is obtained from a strong field expansion in the electroweak standard model. The interaction is expressed by a Chern-Simons form of the neutrino current and the electromagnetic vector potential of the coupling strength proportional to $\frac{n_e}{B}\times e{G}_F$. The derivation of the interaction Lagrangian and its properties are presented.

   hep-phastro-ph.SRhep-thPhys.Open(2023)·4 citations
5. 05*

   Gravitino Cosmology Helped by a Right Handed (S)Neutrino

   Gongjun Choi🇨🇳 · Tsutomu T. Yanagida🇨🇳

   In this paper, we discuss interesting scenarios resulting from the interplay between the gravitino and the lightest right-handed (s)neutrino. We consider two gravitino mass regimes vastly separated, that is, $m_{3/2}=\mathcal{O}(100)\mathrm{eV}$ and $m_{3/2}\simeq 100\mathrm{GeV}$. For the former case, a significant amount of the entropy production in the cosmological history to dilute the gravitino relic abundance is unavoidable for consistency with the number of satellite galaxies in the Milky way. We will show that the right-handed (s)neutrino can play the role of the heavy particle whose late time decay provides such an additional radiation. For the later case, the gravitino of $m_{3/2}\simeq 100\mathrm{GeV}$ may resolve the $S_8$ tension as a decaying dark matter. We will show how the lightest right-handed neutrino and its superpartner can help the gravitino decaying dark matter be equipped with a long enough life time and mass degeneracy with a massive decay product to address the $S_8$ tension.

   hep-phastro-ph.COPLB(2022)·15 citations
6. 06*

   Leptoquark Option for $B$-meson Anomalies and Leptonic Signatures

   Hyun Min Lee🇰🇷

   We entertain the option of scalar leptoquarks to explain the anomalies in the semi-leptonic decays of $B$-mesons and the discrepancies in the lepton $(g-2{)}_l$'s including the recent results at Fermilab E989. The $R_{K^{(\ast )}}$ and $R_{D^{(\ast )}}$ anomalies can be accommodated by the specific couplings for triplet and singlet leptoquarks, respectively, subject to the bounds from $B\to K\nu \bar{\nu }$. We discuss the correlation between the leptonic signatures from leptoquarks such as $\mu \to e\gamma$ and the electric dipole moment of electron and show that desirable neutrino masses can be generated dominantly by top-quark loops in the extension of the model with several doublet leptoquarks.

   hep-phPRD(2021)·44 citations
7. 07*

   Resurgence of the QCD Adler function

   Alessio Maiezza🇭🇷 · Juan Carlos Vasquez🇺🇸

   We study the QCD Adler function in the energy region $\approx 0.7-2.5$ GeV, in which the non-perturbative effects become dominant. Our analysis is a renormalon-based evaluation using transseries within the resurgence of the Renormalization-Group-Equation and does not require the Operator-Product-Expansion.

   hep-phhep-thPLB(2021)·14 citations
8. 08*

   Analysis of the ${\overline{\Xi }}_{cc}{\Xi }_{cc}$ hexaquark molecular state with the QCD sum rules

   Zhi-Gang Wang🇨🇳

   In this work, we construct the color-singlet-color-singlet type six-quark pseudoscalar current to investigate the ${\overline{\Xi }}_{cc}{\Xi }_{cc}$ hexaquark molecular state with the QCD sum rules, the predicted mass $M_X\sim 7.2\mathrm{GeV}$ supports assigning the $X(7200)$ to be the ${\overline{\Xi }}_{cc}{\Xi }_{cc}$ hexaquark molecular state with the quantum numbers $J^{PC}=0^{-+}$. The $X(7200)$ can decay through fusions of the $\bar{c}c$ and $\bar{q}q$ pairs, we can search for the $X(7200)$ and explore its properties in the $J/\psi J/\psi$, ${\chi }_{c1}{\chi }_{c1}$, $D^{\ast }{\bar{D}}^{\ast }$ and $D_1{\bar{D}}_1$ invariant mass spectrum in the future.

   hep-phPLB(2021)·10 citations
9. 09*

   Axial-vector nucleon-to-delta transition form factors using the complex-mass renormalization scheme

   Y. Ünal🇹🇷 · A. Küçükarslan🇹🇷 · S. Scherer🇩🇪

   We investigate the axial-vector nucleon-to-delta transition form factors in the framework of relativistic baryon chiral perturbation theory at the one-loop order using the complex-mass renormalization scheme. We determine the available six free parameters by fitting to an empirical parametrization of the form factors obtained from the BNL neutrino bubble chamber experiments. A unique feature of our calculation is the prediction of a non-vanishing form factor $C_3^A(Q^2)$. Moreover, our results show a surprising sensitivity to the coupling constant ${\text{g}}_1$ of the leading-order Lagrangian ${\mathcal{L}}_{\pi \Delta }^{(1)}$.

   hep-phnucl-thPRD(2021)·12 citations
10. 10*

    One-loop Corrections to the Higgs Boson Invisible Decay in the Dark Doublet Phase of the N2HDM

    Duarte Azevedo🇵🇹 · Pedro Gabriel🇵🇹 · Margarete Muhlleitner🇩🇪 · Kodai Sakurai🇩🇪 · Rui Santos🇵🇹

    The Higgs invisible decay width may soon become a powerful tool to probe extensions of the Standard Model with dark matter candidates at the Large Hadron Collider. In this work, we calculate the next-to-leading order (NLO) electroweak corrections to the 125 GeV Higgs decay width into two dark matter particles. The model is the next-to-minimal 2-Higgs-doublet model (N2HDM) in the dark doublet phase, that is, only one doublet and the singlet acquire vacuum expectation values. We show that the present measurement of the Higgs invisible branching ratio, BR$(H\to$ invisible $<0.11$), does not lead to constraints on the parameter space of the model at leading order. This is due to the very precise measurements of the Higgs couplings but could change in the near future. Furthermore, if NLO corrections are required not to be unphysically large, no limits on the parameter space can be extracted from the NLO results.

    hep-phJHEP(2021)·21 citations
11. 11*

    Impact of A0 data on the Higgs boson production cross section at the LHC

    Francesco Giuli🇮🇹

    In this talk, we present a way to improve the accuracy of theoretical predictions for Higgs boson production cross sections at the LHC using the measurements of lepton angular distributions. In this regards, we exploit the sensitivity of the lepton angular coefficient associated with the longitudinal Z-boson polarization to the parton density function (PDF) for gluons resolved from the incoming protons, in order to constrain the Higgs boson cross section from gluon fusion processes. We find that high-statistics determinations of the longitudinally polarized angular coefficient at the LHC Run 3 and high-luminosity HL-LHC improve the PDF systematics of the Higgs boson cross section predictions by 50% over a broad range of Higgs boson rapidities. This study has been conducted using the open-source fitting framework xFitter. This talk refers to the following paper: arXiv:2012.10298[hep-ph]

    hep-phhep-ex0 citations
12. 12*

    Consequences of chirally enhanced explanations of $(g-2{)}_{\mu }$ for $h\to \mu \mu$ and $Z\to \mu \mu$

    Andreas Crivellin🇨🇭 · Martin Hoferichter🇨🇭

    With the long-standing tension between experiment and Standard-Model (SM) prediction in the anomalous magnetic moment of the muon $a_{\mu }$ recently reaffirmed by the Fermilab experiment, the crucial question becomes which other observables could be sensitive to the underlying physics beyond the SM to which $a_{\mu }$ may be pointing. While from the effective field theory (EFT) point of view no direct correlations exist, this changes in specific new physics models. In particular, in the case of explanations involving heavy new particles above the electroweak (EW) scale with chiral enhancement, which are preferred to evade exclusion limits from direct searches, correlations with other observables sensitive to EW symmetry breaking are expected. Such scenarios can be classified according to the $SU(2{)}_L$ representations and the hypercharges of the new particles. We match the resulting class of models with heavy new scalars and fermions onto SMEFT and study the resulting correlations with $h\to \mu \mu$ and $Z\to \mu \mu$ decays, where, via $SU(2{)}_L$ symmetry, the latter process is related to $Z\to \nu \nu$ and modified $W$-$\mu$-$\nu$ couplings.

    hep-phhep-exJHEP(2021)·128 citations
13. 13*

    Genuine empirical pressure within the proton

    Adam Freese🇺🇸 · Gerald A. Miller🇺🇸

    A phenomenological extraction of pressure within the proton has recently been performed using JLab CLAS data (arXiv:2104.02031 [nucl-ex]). The extraction used a 3-dimensional Breit frame description in which the initial and final proton states have different momenta. Instead, we obtain the two-dimensional transverse light front pressure densities that incorporate relativistic effects arising from the boosts that cause the initial and final states to differ. The mechanical radius is then determined to be $0.518\pm 0.062_{\mathrm{fit}}\pm 0.126_{\mathrm{sys}}\mathrm{fm}$, which is smaller than the electric charge radius and larger than the light front momentum radius. The forces within the proton are shown to be predominantly repulsive at distances less than $0.43\pm 0.12\mathrm{fm}$ from the center, and predominantly attractive further out.

    hep-phnucl-exnucl-thPRD(2021)·30 citations
14. 14*

    Supersymmetric Interpretation of the Muon $g-2$ Anomaly

    Motoi Endo🇯🇵 · Koichi Hamaguchi🇯🇵 · Sho Iwamoto🇭🇺 · Teppei Kitahara🇯🇵

    The Fermilab Muon $g-2$ collaboration recently announced the first result of measurement of the muon anomalous magnetic moment ($g-2$), which confirmed the previous result at the Brookhaven National Laboratory and thus the discrepancy with its Standard Model prediction. We revisit low-scale supersymmetric models that are naturally capable to solve the muon $g-2$ anomaly, focusing on two distinct scenarios: chargino-contribution dominated and pure-bino-contribution dominated scenarios. It is shown that the slepton pair-production searches have excluded broad parameter spaces for both two scenarios, but they are not closed yet. For the chargino-dominated scenario, the models with $m_{{\tilde{\mu }}_{\mathrm{L}}}\gtrsim m_{{\tilde{\chi }}_1^{\pm }}$ are still widely allowed. For the bino-dominated scenario, we find that, although slightly non-trivial, the region with low $\tan \beta$ with heavy higgsinos is preferred. In the case of universal slepton masses, the low mass regions with $m_{\tilde{\mu }}\lesssim 230$ GeV can explain the $g-2$ anomaly while satisfying the LHC constraints. Furthermore, we checked that the stau-bino coannihilation works properly to realize the bino thermal relic dark matter. We also investigate heavy staus case for the bino-dominated scenario, where the parameter region that can explain the muon $g-2$ anomaly is stretched to $m_{\tilde{\mu }}\lesssim 1.3$ TeV.

    hep-phhep-exJHEP(2021)·110 citations
15. 15*

    Wino-Higgsino dark matter in the MSSM from the $g-2$ anomaly

    Sho Iwamoto🇭🇺 · Tsutomu T. Yanagida🇨🇳 · Norimi Yokozaki🇨🇳

    In this letter, we show that the wino-Higgsino dark matter (DM) is detectable in near future DM direct detection experiments for almost all consistent parameter space in the spontaneously broken supergravity (SUGRA) if the muon g-2 anomaly is explained by the wino-Higgsino loop diagrams. We also point out that the present and future LHC experiments can exclude or confirm this SUGRA explanation of the observed muon g-2 anomaly.

    hep-phhep-exPLB(2021)·44 citations
16. 16*

    Lepton-specific inert two-Higgs-doublet model confronted with the new results for muon and electron g-2 anomalies and multi-lepton searches at the LHC

    Xiao-Fang Han🇨🇳 · Tianjun Li🇨🇳 · Hong-Xin Wang🇨🇳 · Lei Wang🇨🇳 · Yang Zhang🇨🇳

    Combining the multi-lepton searches at the LHC, we study the possibilities of accommodating the new data of muon and electron $g-2$ anomalies in the lepton-specific inert two-Higgs-doublet model. We take the heavy CP-even Higgs as the 125 GeV Higgs, and find the muon and electron $g-2$ anomalies can be explained simultaneously in the region of 5 GeV $<m_h<60$ GeV, 200 GeV $<m_A<620$ GeV, 190 GeV $<m_{H^{\pm }}<620$ GeV for appropriate Yukawa couplings between leptons and inert Higgs. Meanwhile, the model can give a better fit to the data of lepton universality in $\tau$ decays than the SM. Further, the multi-lepton event searches at the LHC impose a stringent upper bound on $m_h$, $m_h<$ 35 GeV.

    hep-phPRD(2021)·54 citations
17. 17*

    Muon $g-2$ and $B$-anomalies from Dark Matter

    Giorgio Arcadi🇮🇹 · Lorenzo Calibbi🇨🇳 · Marco Fedele🇩🇪 · Federico Mescia🇪🇸

    In the light of the recent result of the Muon g-2 experiment and the update on the test of lepton flavour universality $R_K$ published by the LHCb collaboration, we systematically build and discuss a set of models with minimal field content that can simultaneously give: (i) a thermal Dark Matter candidate; (ii) large loop contributions to $b\to s\ell \ell$ processes able to address $R_K$ and the other $B$ anomalies; (iii) a natural solution to the muon $g-2$ discrepancy through chirally-enhanced contributions.

    hep-phhep-exPRL(2021)·91 citations
18. 18*

    Confronting spin-3/2 and other new fermions with the muon g-2 measurement

    Juan C. Criado🇬🇧 · Abdelhak Djouadi🇪🇸 · Niko Koivunen🇪🇪 · Kristjan Müürsepp🇪🇪 · Martti Raidal🇪🇪 · Hardi Veermäe🇪🇪

    The new measurement of the muon's anomalous magnetic moment released by the Muon g-2 experiment at Fermilab sets strong constraints on the properties of many new particles. Using an effective field theory approach to the interactions of higher-spin fields, we evaluate the contribution of an electrically neutral and colour singlet spin-3/2 fermion to $(g-2{)}_{\mu }$ and derive the corresponding constraints on its mass and couplings. These constraints are then compared with the ones on spin-1/2 fermions, such as the vector-like leptons that are predicted by various extensions of the Standard Model, the excited leptons which appear in composite models, as well as the charginos and neutralinos of supersymmetric theories. Unlike these new spin-1/2 fermions, the spin-3/2 particles generate only small contributions to the muon anomalous magnetic moment.

    hep-phhep-exhep-thPLB(2021)·17 citations
19. 19*

    Probing the flavor-specific scalar mediator for the muon $(g-2)$ deviation, the proton radius puzzle and the light dark matter production

    Bin Zhu🇨🇳 · Xuewen Liu🇨🇳

    Flavor-specific scalar bosons exist in various Standard Model extensions and couple to a single generation of fermions via a global flavor symmetry breaking mechanism. Given this strategy, we propose a MeV flavor-specific scalar model in dimension-$5$ operator series, which explains the muon g-2 anomaly and proton radius puzzle by coupling with the muon and down-quark at the same time. The framework is consistent with the null result of high-intensity searches. Specifically, the supernova constraints for muon couplings become weakened by including the contribution of down-quark interaction. The parameter space for explaining muon $g-2$ discrepancy is available when $10\%$ energy deposition is required in the energy explosion process in the supernova, but this is ruled out by the $1\%$ energy deposition requirement. We also investigate the searches for mediator and dark matter and the resulting constraints on viable parameter space such as nuclear physics constraints, direct detection for light boosted dark matter, and possible CMB constraints. When compared to conventional dark matter production, light dark matter production has two additional modifications: bound state formation and early kinetic equilibrium decoupling. We are now looking into the implications of these effects on the relic density of light dark matter.

    hep-phSCPMA(2022)·33 citations
20. 20*

    Heavy Bino and Slepton for Muon g-2 Anomaly

    Yuchao Gu🇨🇳 · Ning Liu🇨🇳 · Liangliang Su🇨🇳 · Daohan Wang🇨🇳

    In light of very recent E989 experimental result, we investigate the possibility that heavy sparticles explain the muon g-2 anomaly. We focus on the bino-smuon loop in an effective SUSY scenario, where a light gravitino plays the role of dark matter and other sparticles are heavy. Due to the enhancement of left-right mixing of smuons by heavy higgsinos, the contribution of bino-smuon loop can sizably increase the prediction of muon g-2 to the experimental value. Under collider and vacuum stability constraints, we find that TeV scale bino and smuon can still account for the new muon g-2 anomaly. The implications for LHC phenomenology are also discussed.

    hep-phNPB(2021)·43 citations
21. 21*

    muon $g-2$ anomaly and $\mu$-$\tau$-philic Higgs doublet with a light CP-even component

    Hong-Xin Wang🇨🇳 · Lei Wang🇨🇳 · Yang Zhang🇨🇳

    We examine the possibilities of accommodating the muon $g-2$ anomaly reported by Fermilab in the 2HDM with a discrete $Z_4$ symmetry in which an inert Higgs doublet field ($H,A,H^{\pm }$) has the lepton flavor violation $\mu$-$\tau$ interactions. We study the case of light $H$ (5 GeV $<m_H<$ 115 GeV) and assume the Yukawa matrices to be real and symmetrical. Considering relevant theoretical and experimental constraints, especially for the multi-lepton searches at the LHC, we find the muon $g-2$ anomaly can be explained within $2\sigma$ range in the region of 5 GeV $<m_H<20$ GeV, 130 GeV $<m_A(m_{H^{\pm }})<$ 610 GeV, and 0.005 $<\rho <$ 0.014. Meanwhile, the ${\chi }_{\tau }^2$ fitting the data of lepton flavour universality in the $\tau$ decays approaches to the SM prediction.

    hep-phEPJC(2021)·34 citations
22. 22*

    Dark matter, fine-tuning and $(g-2{)}_{\mu }$ in the pMSSM

    Melissa van Beekveld🇬🇧 · Wim Beenakker🇳🇱 · Marrit Schutten🇳🇱 · Jeremy de Wit🇳🇱

    In this paper we analyze spectra in the phenomenological supersymmetric Standard Model that simultaneously result in the right dark-matter relic density ${\Omega }_{\mathrm{DM}}{h}^2$, offer an explanation for the $(g-2{)}_{\mu }$ discrepancy $\Delta a_{\mu }$ and are minimally fine-tuned. We discuss the LHC phenomenology resulting from these spectra and the sensitivity of dark-matter direct detection experiments to these spectra. We find that the latter type of experiments with sensitivity to the spin-dependent dark-matter-nucleon scattering cross section ${\sigma }_{\mathrm{SD},\mathrm{p}}$ will probe all of our found solutions.

    hep-phSciPost Phys.(2021)·83 citations
23. 23*

    Explanations for anomalies of muon anomalous magnetic dipole moment, $b\to s\mu \bar{\mu }$ and radiative neutrino masses in a leptoquark model

    Takaaki Nomura🇨🇳 · Hiroshi Okada🇰🇷

    We propose a leptoquark model simultaneously to explain anomalies of muon anomalous magnetic dipole moment and $b\to s\mu \bar{\mu }$ in light of experimental reports very recently. Here, we satisfy several stringent constraints such as $\mu \to e\gamma$ and meson mixings. In addition, we find these leptoquarks also play an role in generating tiny neutrino masses at one-loop level without introducing any additional symmetries. We have numerical analysis and show how degrees our parameter space is restricted.

    hep-phPRD(2021)·46 citations
24. 24*

    A fake doublet solution to the muon anomalous magnetic moment

    Damiano Anselmi🇮🇹 · Kristjan Kannike🇪🇪 · Carlo Marzo🇪🇪 · Luca Marzola🇪🇪 · Aurora Melis🇪🇪 · Kristjan Müürsepp🇪🇪 · Marco Piva🇪🇪 · Martti Raidal🇪🇪

    Extensions to the Standard Model that use strictly off-shell degrees of freedom - the fakeons - allow for new measurable interactions at energy scales usually precluded by the constraints that target the on-shell propagation of new particles. Here we employ the interactions between a new fake scalar doublet and the muon to explain the recent Fermilab measurement of its anomalous magnetic moment. Remarkably, unlike in the case of usual particles, the experimental result can be matched for fakeon masses below the electroweak scale without contradicting the stringent precision data and collider bounds on new light degrees of freedom. Our analysis, therefore, demonstrates that the fakeon approach offers unexpected viable possibilities to model new physics naturally at low scales.

    hep-phhep-exhep-thPRD(2021)·15 citations
25. 25*

    Muon $g-2$ Anomaly in Anomaly Mediation

    Wen Yin🇯🇵

    The long-standing muon $g-2$ anomaly has been confirmed recently at the Fermilab. The combined discrepancy from Fermilab and Brookhaven results shows a difference from the theory at a significance of 4.2 $\sigma$. In addition, the LHC has updated the lower mass bound of a pure wino. In this letter, we study to what extent the $g-2$ can be explained in anomaly mediation scenarios, where the pure wino is the dominant dark matter component. To this end, we derive some model-independent constraints on the particle spectra and $g-2$. We find that the $g-2$ explanation at the 1$\sigma$ level is driven into a corner if the higgsino threshold correction is suppressed. On the contrary, if the threshold correction is sizable, the $g-2$ can be explained. In the whole viable parameter region, the gluino mass is at most $2-4$TeV, the bino mass is at most $2$TeV, and the wino dark matter mass is at most $1-2$TeV. If the muon $g-2$ anomaly is explained in the anomaly mediation scenarios, colliders and indirect search for the dark matter may find further pieces of evidence in the near future. Possible UV models for the large threshold corrections are discussed.

    hep-phhep-exJHEP(2021)·61 citations
26. 26*

    GUT-scale constrained SUSY in light of E989 muon g-2 measurement

    Fei Wang🇨🇳 · Lei Wu🇨🇳 · Yang Xiao🇨🇳 · Jin Min Yang🇨🇳 · Yang Zhang🇨🇳

    The new FNAL result of the muon $g-2$, combined with the BNL result, shows a 4.2$\sigma$ deviation from the SM. We use the new data of the muon $g-2$ to revisit several GUT-scale constrained SUSY models with the constraints from the LHC searches, the dark matter detection, the flavor data and the electroweak vacuum stability. We first demonstrate the tension between the muon $g-2$ and other experimental measurements in the CMSSM/mSUGRA. Then after discussing the possible ways to alleviate such a tension and showing the muon $g-2$ in pMSSM under relevant experimental constraints, we survey several extensions of the CMSSM/mSUGRA with different types of universal boundary conditions at the GUT scale. Finally, we briefly discuss the muon $g-2$ in other popular SUSY breaking mechanisms, namely the GMSB and AMSB mechanisms and their extensions.

    hep-phNPB(2021)·101 citations
27. 27*

    Challenges for an axion explanation of the muon $g-2$ measurement

    Manuel A. Buen-Abad🇺🇸 · JiJi Fan🇺🇸 · Matthew Reece🇺🇸 · Chen Sun🇮🇱

    The discrepancy between the muon $g-2$ measurement and the Standard Model prediction points to new physics around or below the weak scale. It is tantalizing to consider the loop effects of a heavy axion (in the general sense, also known as an axion-like particle) coupling to leptons and photons as an explanation for this discrepancy. We provide an updated analysis of the necessary couplings, including two-loop contributions, and find that the new physics operators point to an axion decay constant on the order of 10s of GeV. This poses major problems for such an explanation, as the axion couplings to leptons and photons must be generated at low scales. We outline some possibilities for how such couplings can arise, and find that these scenarios predict new charged matter at or below the weak scale and new scalars can mix with the Higgs boson, raising numerous phenomenological challenges. These scenarios also all predict additional contributions to the muon $g-2$ itself, calling the initial application of the axion effective theory into question. We conclude that there is little reason to favor an axion explanation of the muon $g-2$ measurement relative to other models postulating new weak-scale matter.

    hep-phJHEP(2021)·80 citations
28. 28*

    The FIMP-WIMP dark matter in the extended singlet scalar model

    Pritam Das🇮🇳 · Mrinal Kumar Das🇮🇳 · Najimuddin Khan🇮🇳

    We explore the simplest viable dark matter model with a real singlet scalar, vector-like singlet and doublet fermions. The Yukawa couplings associated with the fermion sector play a crucial role in getting the current relic density through Freeze-in and Freeze-out mechanism. We discuss the constraints from the recent muon anomalous magnetic moment experimental data and relic density. We also perform the collider analysis for the FIMP dark matter in the context of 14 TeV LHC experiments with the MATHUSLA100/200 detector. Our analysis shows that one can get enough events $>3$ for heavy charged fermion track at 14 TeV LHC with an integrated luminosity $\mathcal{L}=10^6\mathrm{f}{\mathrm{b}}^{-1}$.

    hep-phNPB(2022)·34 citations
29. 29*

    A common origin of muon g-2 anomaly, Galaxy Center GeV excess and AMS-02 anti-proton excess in the NMSSM

    Murat Abdughani🇨🇳 · Yi-Zhong Fan🇨🇳 · Lei Feng🇨🇳 · Yue-Lin Sming Tsai🇨🇳 · Lei Wu🇨🇳 · Qiang Yuan🇨🇳

    The supersymmetric model is one of the most attractive extensions of the Standard Model of particle physics. In light of the most recently reported anomaly of the muon g-2 measurement by the FermiLab E989 experiment, and the excesses of gamma rays at the Galactic center observed by Fermi-LAT space telescope, as well as the antiproton excess observed by the Alpha Magnetic Spectrometer, we propose to account for all these anomalies or excesses in the Next-to-Minimal Supersymmetric Standard Model. Considering various experimental constraints including the Higgs mass, B-physics, collider data, dark matter relic density and direct detections, we find that a $\sim 60$ GeV bino-like neutralino is able to successfully explain all these observations. Our scenario can be sensitively probed by future direct detection experiments.

    hep-phastro-ph.HESci.Bull.(2021)·73 citations
30. 30*

    Muon $g-2$ in a two-Higgs-doublet model with a type-II seesaw mechanism

    Chuan-Hung Chen🇹🇼 · Cheng-Wei Chiang🇹🇼 · Takaaki Nomura🇨🇳

    We study the two-Higgs-doublet model with type-II seesaw mechanism. In view of constraints from the Higgs data, we consider the aligned two-Higgs-doublet scheme and its effects on muon anomalous magnetic dipole moment, $a_{\mu }$, including both one-loop and two-loop Barr-Zee type diagrams. Thanks to a sizable trilinear scalar coupling, the Barr-Zee type diagrams mediated by the Higgs triplet fields have a dominant effect on $a_{\mu }$. In particular, unlike the usual two-Higgs-doublet models that require exotic Higgs bosons light in mass, the masses of the corresponding particles in the model are of $\mathcal{O}(100)$~GeV. The doubly-charged Higgs boson presents a different decay pattern from the usual Higgs triplet model and thus calls for a new collider search strategy, such as multi-$\tau$ searches at the LHC.

    hep-phhep-exPRD(2021)·38 citations
31. 31*

    Probing the Dark Axion Portal with Muon Anomalous Magnetic Moment

    Shao-Feng Ge🇨🇳 · Xiao-Dong Ma🇨🇳 · Pedro Pasquini🇨🇳

    We propose a new scenario of using the dark axion portal at one-loop level to explain the recently observed muon anomalous magnetic moment by the Fermilab Muon g-2 experiment. Both axion/axion-like particle (ALP) and dark photon are involved in the same vertex with photon. Although ALP or dark photon alone cannot explain muon $g-2$, since the former provides only negative contribution while the latter has very much constrained parameter space, dark axion portal can save the situation and significantly extend the allowed parameter space. The observed muon anomalous magnetic moment provides a robust probe of the dark axion portal scenario.

    hep-phhep-exEPJC(2021)·54 citations
32. 32*

    Muon and electron g-2 and proton and cesium weak charges implications on dark ${\mathbf{Z}}_{\mathbf{d}}$ models

    M. Cadeddu🇮🇹 · N. Cargioli🇮🇹 · F. Dordei🇮🇹 · C. Giunti🇮🇹 · E. Picciau🇮🇹

    Theories beyond the standard model involving a sub-GeV-scale vector $Z_d$ mediator have been largely studied as a possible explanation of the experimental values of the muon and electron anomalous magnetic moments. Motivated by the recent determination of the anomalous muon magnetic moment performed at Fermilab, we derive the constraints on such a model obtained from the magnetic moment determinations and the measurements of the proton and cesium weak charge, $Q_W$, performed at low-energy transfer. In order to do so, we revisit the determination of the cesium $Q_W$ from the atomic parity violation experiment, which depends critically on the value of the average neutron rms radius of ${}^{133}\text{Cs}$, by determining the latter from a practically model-independent extrapolation from the recent average neutron rms radius of ${}^{208}\text{Pb}$ performed by the PREX-2 Collaboration. From a combined fit of all the aforementioned experimental results, we obtain rather precise limits on the mass and the kinetic mixing parameter of the $Z_d$ boson, namely $m_{Z_d}=47{}_{-16}^{+61}\mathrm{MeV}$ and $\epsilon =2.3{}_{-0.4}^{+1.1}\times 10^{-3}$, when marginalizing over the $Z-Z_d$ mass mixing parameter $\delta$.

    hep-phPRD(2021)·63 citations
33. 33*

    Semi-secretly interacting ALP as an explanation of Fermilab muon $g-2$ measurement

    Vedran Brdar🇺🇸 · Sudip Jana🇩🇪 · Jisuke Kubo🇩🇪 · Manfred Lindner🇩🇪

    The muon anomalous magnetic moment measurement has, for more than a decade, been a long-standing anomaly hinting the physics beyond the Standard Model (BSM). The recently announced results from muon $g-2$ collaboration, corresponding to 3.3$\sigma$ deviation from Standard Model value (4.2$\sigma$ in combination with previous measurement) are strengthening the need for new physics coupled to muons. In this letter, we propose a novel scenario in which Standard Model (SM) is augmented by an axion-like particle (ALP) and vector-like fermions. We find that such a model admits an excellent interpretation of recent muon $g-2$ measurement through quantum process featuring ALP interacting with muons and newly introduced fermions. Previously proposed explanations with ALPs utilize interactions with photons and/or SM fermions. Therefore, in this letter we complement and extend such scenarios. We also discuss collider prospects for the model as well as the possibility that ALP is long lived or stable dark matter (DM) candidate.

    hep-phhep-exPLB(2021)·30 citations
34. 34*

    Improved $(g-2{)}_{\mu }$ measurement and singlino dark matter in $\mu$-term extended ${\mathbb{Z}}_3$-NMSSM

    Junjie Cao🇨🇳 · Jingwei Lian🇨🇳 · Yusi Pan🇨🇳 · Di Zhang🇨🇳 · Pengxuan Zhu🇨🇳

    Very recently, a Fermilab report of muon $g-2$ showed a $4.2\sigma$ discrepancy between it and the standard model (SM) prediction. Motivated by this inspiring result and the increasing tension in supersymmetric interpretation of the anomalous magnetic moment, it is argued that in the general next-to-minimal supersymmetric standard model (GNMSSM), a singlino-dominated neutralino can act as a feasible dark matter (DM) candidate in explaining the discrepancy naturally. In this case, the singlino-dominated DM and singlet-dominated Higgs bosons can form a secluded DM sector with ${\tilde{\chi }}_1^0{\tilde{\chi }}_1^0\to h_s{A}_s$ responsible for the measured DM relic abundance. when $m_{{\tilde{\chi }}_1^0}\gtrsim 150\mathrm{GeV}$ and the Yukawa coupling $\kappa$ is around $0.2$. This sector communicates with the SM sector by weak singlet-doublet Higgs mixing, so the scatterings of the singlino-dominated DM with nucleons are suppressed. Furthermore, due to the singlet nature of the DM and the complex mass hierarchy, sparticle decay chains in the GNMSSM are lengthened in comparison with the prediction of the minimal supersymmetric standard model. These characteristics lead to sparticle detection at the Large Hadron Collider (LHC) being rather tricky. This study surveys a specific scenario of the GNMSSM, which extends the ${\mathbb{Z}}_3$-NMSSM by adding an explicit $\mu$-term, to reveal the features. It indicates that the theory can readily explain the discrepancy of the muon anomalous magnetic moment without conflicting with the experimental results in DM and Higgs physics, and the LHC searches for sparticles.

    hep-phJHEP(2021)·79 citations
35. 35*

    The new "MUON G-2" Result and Supersymmetry

    Manimala Chakraborti🇵🇱 · Sven Heinemeyer🇪🇸 · Ipsita Saha🇯🇵

    The electroweak (EW) sector of the Minimal Supersymmetric Standard Model (MSSM), with the lightest neutralino as Dark Matter (DM) candidate, can account for a variety of experimental data. This includes the DM content of the universe, DM direct detection limits, EW SUSY searches at the LHC and in particular the so far persistent $3-4\sigma$ discrepancy between the experimental result for the anomalous magnetic moment of the muon, $(g-2{)}_{\mu }$, and its Standard Model (SM) prediction. The recently published ``MUON G-2'' result is within $0.8\sigma$ in agreement with the older BNL result on $(g-2{)}_{\mu }$. The combination of the two results was given as $a_{\mu }^{\exp }=(11659206.1\pm 4.1c)\times 10^{-10}$, yielding a new deviation from the SM prediction of $\Delta a_{\mu }=(25.1\pm 5.9)\times 10^{-10}$, corresponding to $4.2\sigma$. Using this improved bound we update the results presented in [1] and set new upper limits on the allowed parameters space of the EW sector of the MSSM. We find that with the new $(g-2{)}_{\mu }$ result the upper limits on the (next-to-) lightest SUSY particle are in the same ballpark as previously, yielding updated upper limits on these masses of $\sim 600$ GeV. In this way, a clear target is confirmed for future (HL-)LHC EW searches, as well as for future high-energy $e^{+}{e}^{-}$ colliders, such as the ILC or CLIC.

    hep-phEPJC(2021)·92 citations
36. 36*

    Muon $g-2$ in Gauge Mediation without SUSY CP Problem

    Masahiro Ibe🇯🇵 · Shin Kobayashi🇯🇵 · Yuhei Nakayama🇯🇵 · Satoshi Shirai🇯🇵

    We discuss gauge mediated supersymmetry breaking models which explain the observed muon anomalous magnetic moment and the Higgs boson mass simultaneously. The successful explanation requires the messenger sector which violates the relation motivated by the grand unification theory (GUT). The naive violation of the GUT relation, however, ends up with the CP problem. We propose a model in which the phases of the gaugino masses are aligned despite the violation of the GUT relation. We also consider a model which generates the $\mu$-term and the additional Higgs soft masses squared without causing CP violation. As a result, we find a successful model which explains the muon anomalous magnetic moment and the Higgs boson mass. The model is also free from the CP, flavor-changing neutral current and the lepton flavor violation problems caused by the subdominant gravity mediation effects.

    hep-phJHEP(2021)·37 citations
37. 37*

    Muon $g-2$ and Co-annihilating Dark Matter in the MSSM

    Peter Cox🇦🇺 · Chengcheng Han🇨🇳 · Tsutomu T. Yanagida🇨🇳

    We demonstrate that the recent measurement of the anomalous magnetic moment of the muon and dark matter can be simultaneously explained within the Minimal Supersymmetric Standard Model. Dark matter is a mostly-bino state, with the relic abundance obtained via co-annihilations with either the sleptons or wino. The most interesting regions of parameter space will be tested by the next generation of dark matter direct detection experiments.

    hep-phPRD(2021)·73 citations
38. 38*

    Muon $g-2$ Anomaly and Neutrino Magnetic Moments

    K.S. Babu🇺🇸 · Sudip Jana🇩🇪 · Manfred Lindner🇩🇪 · Vishnu P.K

    We show that a unified framework based on an $SU(2{)}_H$ horizontal symmetry which generates a naturally large neutrino transition magnetic moment and explains the XENON1T electron recoil excess also predicts a positive shift in the muon anomalous magnetic moment. This shift is of the right magnitude to be consistent with the Brookhaven measurement as well as the recent Fermilab measurement of the muon $g-2$. A relatively light neutral scalar from a Higgs doublet with mass near 100 GeV contributes to muon $g-2$, while its charged partner induces the neutrino magnetic moment. In contrast to other multi-scalar theories, in the model presented here there is no freedom to control the sign and strength of the muon $g-2$ contribution. We analyze the collider tests of this framework and find that the HL-LHC can probe the entire parameter space of these models.

    hep-phhep-exhep-latJHEP(2021)·46 citations
39. 39*

    Muon g-2 and CP violation in MSSM

    Chengcheng Han🇨🇳

    We study the constraints of the CP violation in the muon $g-2$ preferred region of the minimal supersymmetric standard model assuming a universal slepton masses within first two generations. We present two particular scenarios where the $g-2$ anomaly is predicted within 2 $\sigma$ level mainly through the chargino loop or the bino loop. We found that for both cases the electron EDM experiment already highly constrained the CP phase of the parameters: either the Arg[$\mu M_1]$ or Arg[$\mu M_2]$ should be smaller than $\mathcal{O}$(2-3)$\times 10^{-5}$. If the muon $g-2$ anomaly is explained by the MSSM, a particular SUSY breaking mechanism is needed to guarantee the small CP phase of SUSY parameters. Otherwise, a tuning of $\mathcal{O}(10^{-5})$ is needed to cancel the phase in a general CP violated SUSY model.

    hep-ph52 citations
40. 40*

    The new $(g-2{)}_{\mu }$ result and the $\mu \nu$SSM

    Sven Heinemeyer🇪🇸 · Essodjolo Kpatcha🇪🇸 · Iñaki Lara🇵🇱 · Daniel E. López-Fogliani🇦🇷 · Carlos Muñoz🇪🇸 · Natsumi Nagata🇯🇵

    The $\mu \nu$SSM is a highly predictive alternative model to the MSSM. In particular, the electroweak sector of the model can explain the longstanding discrepancy between the experimental result for the anomalous magnetic moment of the muon, $(g-2{)}_{\mu }$, and its Standard Model prediction, while being in agreement with all other theoretical and experimental constraints. The recently published MUON G-2 result is within $0.8\sigma$ in agreement with the older BNL result on $(g-2{)}_{\mu }$. The combined result was announced as $a_{\mu }^{\exp }=(11659206.1\pm 4.1)\times 10^{-10}$, yielding a new deviation from the Standard Model prediction of $\Delta a_{\mu }=(25.1\pm 5.9)\times 10^{-10}$, corresponding to $4.2\sigma$. Using this improved bound we update the analysis in the $\mu \nu$SSM as presented in Ref. [1] and set new limits on the allowed parameters space of the electroweak sector of the model. We conclude that significant regions of the model can explain the new $(g-2{)}_{\mu }$ data.

    hep-phhep-exEPJC(2021)·35 citations
41. 41*

    Implications of the Muon g-2 result on the flavour structure of the lepton mass matrix

    Lorenzo Calibbi🇨🇳 · M.L. López-Ibáñez🇨🇳 · Aurora Melis🇪🇪 · Oscar Vives🇪🇸

    The confirmation of the discrepancy with the Standard Model predictions in the anomalous magnetic moment by the Muon g-2 experiment at Fermilab points to a low scale of new physics. Flavour symmetries broken at low energies can account for this discrepancy but these models are much more restricted, as they would also generate off-diagonal entries in the dipole moment matrix. Therefore, if we assume that the observed discrepancy in the muon $g-2$ is explained by the contributions of a low-energy flavor symmetry, lepton flavour violating processes can constrain the structure of the lepton mass matrices and therefore the flavour symmetries themselves predicting these structures. We apply these ideas to several discrete flavour symmetries popular in the leptonic sector, such as $\Delta (27)$, $A_4$, and $A_5⋉\mathrm{CP}$.

    hep-phEPJC(2021)·41 citations
42. 42*

    Confirming $U(1{)}_{L_{\mu }-L_{\tau }}$ as a solution for $(g-2{)}_{\mu }$ with neutrinos

    D.W.P. Amaral🇬🇧 · D.G. Cerdeno🇪🇸 · A. Cheek🇧🇪 · P. Foldenauer🇬🇧

    The recent measurement of the muon anomalous magnetic moment by the Fermilab E989 experiment, when combined with the previous result at BNL, has confirmed the tension with the SM prediction at $4.2\sigma$ CL, strengthening the motivation for new physics in the leptonic sector. Among the different particle physics models that could account for such an excess, a gauged $U(1{)}_{L_{\mu }-L_{\tau }}$ stands out for its simplicity. In this article, we explore how the combination of data from different future probes can help identify the nature of the new physics behind the muon anomalous magnetic moment. In particular, we contrast $U(1{)}_{L_{\mu }-L_{\tau }}$ with an effective $U(1{)}_{L_{\mu }}$-type model. We first show that muon fixed target experiments (such as NA64$\mu$) will be able to measure the coupling of the hidden photon to the muon sector in the region compatible with $(g-2{)}_{\mu }$, and will have some sensitivity to the hidden photon's mass. We then study how experiments looking for coherent elastic neutrino-nucleus scattering (CE$\nu$NS) at spallation sources will provide crucial additional information on the kinetic mixing of the hidden photon. When combined with NA64$\mu$ results, the exclusion limits (or reconstructed regions) of future CE$\nu$NS detectors will also allow for a better measurement of the mediator mass. Finally, the observation of nuclear recoils from solar neutrinos in dark matter direct detection experiments will provide unique information about the coupling of the hidden photon to the tau sector. The signal expected for $U(1{)}_{L_{\mu }-L_{\tau }}$ is larger than for $U(1{)}_{L_{\mu }}$ with the same kinetic mixing, and future multi-ton liquid xenon proposals (such as DARWIN) have the potential to confirm the former over the latter.

    hep-phEPJC(2021)·87 citations
43. 43*

    Muon g-2 in Lepton Portal Dark Matter

    Yang Bai🇺🇸 · Joshua Berger🇺🇸

    The Lepton Portal Dark Matter model, in which dark matter states only coupling to the charged leptons, can explain the excess of the muon anomalous magnetic moment measured by the Muon $g-2$ experiment. In this paper, we demonstrate that real, charge-neutral scalar dark matter with a large number of internal degrees of freedom and a mass approximately degenerate with the charged fermionic mediator state can accommodate the $(g-2{)}_{\mu }$ excess. The model remains consistent with the dark matter relic abundance, direct detection, and indirect detection constraints. The dark matter and its charged fermion partner masses are constrained to be below around 200 GeV. The high-luminosity LHC and future lepton colliders, as well as indirect searches at CTA and GAMMA-400, can test this scenario.

    hep-phastro-ph.HEhep-ex36 citations
44. 44*

    The Tiny (g-2) Muon Wobble from Small-$\mu$ Supersymmetry

    Sebastian Baum🇺🇸 · Marcela Carena🇺🇸 · Nausheen R. Shah🇺🇸 · Carlos E. M. Wagner🇺🇸

    A new measurement of the muon anomalous magnetic moment has been reported by the Fermilab Muon g-2 collaboration and shows a $4.2\sigma$ departure from the most precise and reliable calculation of this quantity in the Standard Model. Assuming that this discrepancy is due to new physics, we concentrate on a simple supersymmetric model that also provides a dark matter explanation in a previously unexplored region of supersymmetric parameter space. Such interesting region can realize a Bino-like dark matter candidate compatible with all current direct detection constraints for small to moderate values of the Higgsino mass parameter $|\mu |$. This in turn would imply the existence of light additional Higgs bosons and Higgsino particles within reach of the high-luminosity LHC and future colliders. We provide benchmark scenarios that will be tested in the next generation of direct dark matter experiments and at the LHC.

    hep-phhep-exJHEP(2022)·80 citations
45. 45*

    Simple models with both baryon and lepton number violation by two units

    Andreas Helset🇺🇸 · Clara Murgui🇺🇸 · Mark B. Wise🇺🇸

    We construct simple renormalizable extensions of the standard model where the leading baryon number violating processes have $\Delta B=\pm \Delta L=-2$. These models contain additional scalars. The simplest models contain a color singlet and a colored sextet. For such baryon number violation to be observed in experiments, the scalars cannot be much heavier than a few TeV. We find that such models are strongly constrained by LHC physics, LEP physics, and flavor physics.

    hep-phhep-thPRD(2021)·8 citations
46. 46*

    The Time-reversal Odd Side of a Jet

    Xiaohui Liu🇨🇳 · Hongxi Xing🇨🇳

    We re-examine the jet probes of the nucleon spin and flavor structures. We find for the first time the time-reversal odd (T-odd) component of a jet, conventionally thought to vanish, can survive due to the non-perturbative fragmentation and hadronization effects and could be testable. This additional contribution of a jet will lead to novel jet phenomena relevant for unlocking the access to several spin structures of the nucleon, which were thought to be impossible by using jets. As examples, we show how the T-odd constituent can couple to the proton transversity at the Electron Ion Collider (EIC) and can give rise to the anisotropy in the jet production in $e^{+}{e}^{-}$ annihilations. We expect the T-odd contribution of the jet to have broad applications in high energy nuclear physics.

    hep-phhep-exnucl-exnucl-thFund.Res.(2023)·19 citations
47. 47*

    Kubo estimation of the electrical conductivity for a hot relativistic fluid in the presence of a magnetic field

    Sarthak Satapathy🇮🇳 · Snigdha Ghosh🇮🇳 · Sabyasachi Ghosh🇮🇳

    We have explored the multi-component structure of electrical conductivity of relativistic Fermionic and Bosonic fluid in presence of magnetic field by using Kubo approach. This is done by explicitly evaluating the thermo-magnetic vector current spectral functions using the real time formalism of finite temperature field theory and the Schwinger proper time formalism. In absence of magnetic field, the one-loop diagramatic representation of Kubo expression of any transport coefficients is exactly same with relaxation time approximation (RTA) based expression, but this equality does not hold for finite magnetic field picture due to lacking of proper implementation of quantum effect in latter approach. We have shown this discrepancy for particular transport coefficient - electrical conductivity, whose starting point in Kubo approach will be electromagnetic current-current correlator and its one-loop skeleton diagram carrying two scalar/Dirac propagators for scalar/Dirac fluid. Through a numerical comparison between RTA and Kubo expressions of conductivity components (parallel and perpendicular), we have attempted to interpret detail quantum field theoretical effect, contained by Kubo expression but not by RTA expression. In classical RTA expression we get magnetic field independent parallel conductivity due to zero Lorentz force but in field theoretical Kubo expression, it decreases and increases with the magnetic field for scalar and Dirac medium respectively due to Landau quantization effect. This parallel component of conductivity can be interpreted as zero momentum limit of quantum fluctuation with same Landau level internal lines. While for perpendicular component of conductivity, fluctuation with Landau level differences $\pm 1$ are noticed, which might be a new realization of transportation in field theoretical sector.

    hep-phcond-mat.mes-hallnucl-thPRD(2021)·35 citations
48. 48*

    Holographic QCD and magnetic fields

    Umut Gursoy🇳🇱

    We review the holographic approach to electromagnetic phenomena in large N QCD. After a brief discussion of existing holographic models, we concentrate on the improved holographic QCD model extended to include magnetically induced phenomena. We explore the influence of magnetic fields on the QCD ground state, focusing on (inverse) magnetic catalysis of chiral condensate, investigate the phase diagram of the theory as a function of magnetic field, temperature and quark chemical potential, and, finally discuss effects of magnetic fields on the quark-anti-quark potential, shear viscosity, speed of sound and magnetization.

    ↳ hep-thhep-phEPJA(2021)·17 citations
49. 49*

    Measurement of Neutron Lifetime and Purcell Effect

    Fei He🇨🇳 · Ka-Di Zhu🇨🇳

    Purcell effect predicts that spontaneous radiation is not an intrinsic property of matter, but is affected by the environment in which it is located, and is the result of the interaction of matter and field. Purcell effect can be inferred from Fermi Gold rule through strict quantum electrodynamics (QED), and through it can achieve the enhancement or suppression of radiation. We suggest that, in principle, the Purcell effect can be detected at the percentage level of neutron decay in experiments with trapped ultra-cold neutrons. As a test of our claim, we propose a currently achievable experimental protocol that can detect whether Purcell effect has occurred in an trapped ultra-cold neutron lifetime measurement experiment. Finally, we discuss the discrepancy in current methods of measuring neutron lifetime, which may be caused by different experimental setups.

    ↳ nucl-thhep-phquant-ph1 citation
50. 50*

    On the origin of the asymmetry of the ejecta structure and explosion of G350.1$-$0.3

    Tomoya Tsuchioka🇯🇵 · Yasunobu Uchiyama🇯🇵 · Ryota Higurashi🇯🇵 · Hiroyoshi Iwasaki🇯🇵 · Shumpei Otsuka🇯🇵 · Shinya Yamada🇯🇵 · Toshiki Sato🇯🇵

    We present X-ray analysis of the ejecta of supernova remnant G350.1$-$0.3 observed with Chandra and Suzaku, and clarify the ejecta's kinematics over a decade and obtain a new observational clue to understanding the origin of the asymmetric explosion. Two images of Chandra X-ray Observatory taken in 2009 and 2018 are analyzed in several methods, and enable us to measure the velocities in the plane of the sky. A maximum velocity is 4640$\pm$290 km s${}^{-1}$ (0.218$\pm$0.014 arcsec yr${}^{-1}$) in the eastern region in the remnant. These findings trigger us to scrutinize the Doppler effects in the spectra of the thermal emission, and the velocities in the line-of-sight direction are estimated to be a thousand km s${}^{-1}$. The results are confirmed by analyzing the spectra of Suzaku. Combining the proper motions and line-of-sight velocities, the ejecta's three-dimensional velocities are $\sim$3000-5000 km s${}^{-1}$. The center of the explosion is more stringently constrained by finding the optimal time to reproduce the observed spatial expansion. Our findings that the age of the SNR is estimated at most to be 655 years, and the CCO is observed as a point source object against the SNR strengthen the 'hydrodynamical kick' hypothesis on the origin of the remnant.

    ↳ astro-ph.HEhep-phApJ(2021)·8 citations
51. 51*

    Isotropic X-ray bound on Primordial Black Hole Dark Matter

    J. Iguaz · P. D. Serpico · T. Siegert

    We revisit the constraints on evaporating primordial black holes (PBHs) from the isotropic X-ray and soft gamma-ray background in the mass range $10^{16}-10^{18}$ g. We find that they are stronger than usually inferred due to two neglected effects: i) The contribution of the annihilation radiation due to positrons emitted in the evaporation process. ii) The high-latitude, Galactic contribution to the measured isotropic flux. We study the dependence of the bounds from the datasets used, the positron annihilation conditions, and the inclusion of the astrophysical background. We push the exclusion limit for non-spinning PBH with monochromatic mass function as the totality of dark matter to 1.5$\times 10^{17}$g, which represents a $\sim$15$\%$ improvement with respect to earlier bounds and translates into almost an order of magnitude improvement in the PBH fraction in the already probed region. We also show that the inclusion of spin and/or an extended, log-normal mass function lead to tighter bounds. Our study suggests that the isotropic flux is an extremely promising target for future missions in improving the sensitivity to PBHs as candidates for dark matter.

    ↳ astro-ph.COhep-phPRD(2021)·54 citations
52. 52*

    Wave packet approach to quantum correlations in neutrino oscillations

    Massimo Blasone🇮🇹 · Silvio De Siena🇮🇹 · Cristina Matrella🇮🇹

    Quantum correlations provide a fertile testing ground for investigating fundamental aspects of quantum physics in various systems, especially in the case of relativistic (elementary) particle systems as neutrinos. In a recent paper, Ming et al. (Ming et al. Eur.Phys.J.C 80 (2020) 275), in connection with results of Daya-Bay and MINOS experiments, have studied the quantumness in neutrino oscillations in the framework of plane-wave approximation. We extend their treatment by adopting the wave packet approach that accounts for effects due to localization and decoherence. This leads to a better agreement with experimental results, in particular for the case of MINOS experiment.

    ↳ quant-phhep-phEPJC(2021)·53 citations
53. 53*

    The Eikonal Approach to Gravitational Scattering and Radiation at $\mathcal{O}(G^3)$

    Paolo Di Vecchia🇩🇰 · Carlo Heissenberg🇸🇪 · Rodolfo Russo🇬🇧 · Gabriele Veneziano🇨🇭

    Using $\mathcal{N}=8$ supergravity as a theoretical laboratory, we extract the 3PM gravitational eikonal for two colliding massive scalars from the classical limit of the corresponding elastic two-loop amplitude. We employ the eikonal phase to obtain the physical deflection angle and to show how its non-relativistic (NR) and ultra-relativistic (UR) regimes are smoothly connected. Such a smooth interpolation rests on keeping contributions to the loop integrals originating from the full soft region, rather than restricting it to its potential sub-region. This task is efficiently carried out by using the method of differential equations with complete near-static boundary conditions. In contrast to the potential-region result, the physical deflection angle includes radiation-reaction contributions that are essential for recovering the finite and universal UR limit implied by general analyticity and crossing arguments. We finally discuss the real emission of massless states, which accounts for the imaginary part of the 3PM eikonal and for the dissipation of energy-momentum. Adopting a direct approach based on unitarity and on the classical limit of the inelastic tree-level amplitude, we are able to treat $\mathcal{N}=8$ and General Relativity on the same footing, and to complete the conservative 3PM eikonal in Einstein's gravity by the addition of the radiation-reaction contribution. We also show how this approach can be used to compute waveforms, as well as the differential and integrated spectra, for the different radiated massless fields.

    ↳ hep-thgr-qchep-phJHEP(2021)·291 citations
54. 54*

    Is there any Nambu monopolium out there?

    D.O.R. Azevedo🇧🇷 · M.L. Bispo🇧🇷 · O.M. Del Cima🇧🇷 · D.H.T. Franco🇧🇷 · A.R. Pereira🇧🇷

    Magnetic monopoles have been a subject of study for more than a century since the first ideas by A. Vaschy and P. Curie, circa 1890. In 1974, Y. Nambu proposed a model for magnetic monopoles exploring a parallelism between the broken symmetry Higgs and the superconductivity Ginzburg-Landau theories in order to describe the pions quark-antiquark confinement states. There, Nambu describes an energetic string where its end points behave like two magnetic monopoles with opposite magnetic charges -- quark and antiquark. Consequently, not only the interaction among monopole and antimonopole, mediated by a massive vector boson (Yukawa potential), but also the energetic string (linear potential) contributes to the effective interaction potential. We propose here a monopole-antimonopole non confining attractive interaction of the Nambu-type, and then investigate the formation of bound states, the monopolium. Some necessary conditions for the existence of bound states to be fulfilled by the proposed Nambu-type potential, Kato weakness, Setô and Bargmann conditions, are verified. In the following, ground state energies are estimated for a variety of monopolium reduced mass, from $10^2$MeV to $10^2$TeV, and Compton interaction lengths, from $10^{-2}$am to $10^{-1}$pm, where discussion about non relativistic and relativistic limits validation is carried out.

    ↳ hep-thastro-ph.HEhep-phEPL(2021)·2 citations
55. 55*

    The spatial distribution of Milky Way satellites, gaps in streams and the nature of dark matter

    Mark R. Lovell (1)🇮🇸 · Marius Cautun (2)🇳🇱 · Carlos S. Frenk (3)🇬🇧 · Wojciech A. Hellwing (4)🇵🇱 · Oliver Newton (5) ((1) University of Iceland, (2) Leiden, (3) ICC Durham, (4) Warsaw, (5) Lyon)🇫🇷

    The spatial distribution of Milky Way (MW) subhaloes provides an important set of observables for testing cosmological models. These include the radial distribution of luminous satellites, planar configurations, and the abundance of dark subhaloes whose existence or absence is key to distinguishing amongst dark matter models. We use the COCO $N$-body simulations of cold dark matter (CDM) and 3.3keV thermal relic warm dark matter (WDM) to predict the satellite spatial distribution in the limit that the impact of baryonic physics is minimal. We demonstrate that the radial distributions of CDM and 3.3keV-WDM luminous satellites are identical if the minimum pre-infall halo mass to form a galaxy is $>10^{8.5}{\mathrm{M}}_{\odot }$. The distribution of dark subhaloes is significantly more concentrated in WDM due to the absence of low mass, recently accreted substructures that typically inhabit the outer parts of a MW halo in CDM. We show that subhaloes of mass $[10^7,10^8]{\mathrm{M}}_{\odot }$ and within 30kpc of the centre are the stripped remnants of larger haloes in both models. Therefore their abundance in WDM is $3\times$ higher than one would anticipate from the overall WDM subhalo population. We estimate that differences between CDM and WDM concentration-mass relations can be probed for subhalo-stream impact parameters $<2$kpc. Finally, we find that the impact of WDM on planes of satellites is likely negligible. Comprehensive comparisons with observations will require further work with high resolution, self-consistent hydrodynamical simulations.

    ↳ astro-ph.GAastro-ph.COhep-phMNRAS(2021)·35 citations
56. 56*

    Non-thermal neutrino-like hot dark matter in light of the $S_8$ tension

    Subinoy Das🇮🇳 · Anshuman Maharana🇮🇳 · Vivian Poulin🇫🇷 · Ravi Kumar Sharma🇮🇳

    The $\Lambda$CDM prediction of $S_8\equiv {\sigma }_8({\Omega }_m/0.3{)}^{0.5}$ -- where ${\sigma }_8$ is the root mean square of matter fluctuations on a 8 $h^{-1}$Mpc scale -- once calibrated on Planck CMB data is $2-3\sigma$ lower than its direct estimate by a number of weak lensing surveys. In this paper, we explore the possibility that the '$S_8$-tension' is due to a non-thermal hot dark matter (HDM) fractional contribution to the universe energy density leading to a power suppression at small-scales in the matter power spectrum. Any HDM models can be characterized by its effective mass $m_{sp}^{\mathrm{eff}}$ and its contribution to the relativistic degrees of freedom at CMB decoupling $\Delta N_{\mathrm{eff}}$. Taking the specific example of a sterile particle produced from the decay of the inflaton during a matter dominated era, we find that from Planck only the tension can be reduced below $2\sigma$, but Planck does not favor a non-zero $m_{sp}^{\mathrm{eff}},\Delta N_{\mathrm{eff}}$. In combination with a measurement of $S_8$ from KIDS1000+BOSS+2dfLenS, the $S_8$-tension would hint at the existence of a particle of mass $m_{sp}^{\mathrm{eff}}\simeq 0.67_{-0.48}^{+0.26}$ $\mathrm{eV}$ with a contribution to $\Delta N_{\mathrm{eff}}\simeq 0.06\pm 0.05$. However, Pantheon and BOSS BAO/$f{\sigma }_8$ data restricts the particle mass to $m_{sp}^{\mathrm{eff}}\simeq 0.48_{-0.36}^{+0.17}$ and contribution to $\Delta N_{\mathrm{eff}}\simeq 0.046_{-0.031}^{+0.004}$. We discuss implications of our results for other canonical non-thermal HDM models -- the Dodelson-Widrow model and a thermal sterile particle with a different temperature in the hidden sector. We report competitive results on such hidden sector temperature which might have interesting implications for particle physics model building, in particular connecting the $S_8$-tension to the longstanding short baseline oscillation anomaly.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2022)·23 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.