Fri·Jul 31, 2020Friday·July 31, 2020

1. 01*

   Probing the Supersymmetric Grand Unified Theories at the Future Proton-Proton Colliders and Hyper-Kamiokande Experiment

   Waqas Ahmed🇨🇳 · Tianjun Li🇨🇳 · Shabbar Raza🇵🇰 · Fang-Zhou Xu🇨🇳

   Gauge coupling unification in the Supersymmetric Standard Models strongly implies the Grand Unified Theories (GUTs). With the grand desert hypothesis, we show that the supersymmetric GUTs can be probed at the future proton-proton (pp) colliders and Hyper-Kamiokande experiment. For the GUTs with the GUT scale $M_{GUT}\le 1.0\times 10^{16}$ GeV, we can probe the dimension-six proton decay via heavy gauge boson exchange at the Hyper-Kamiokande experiment. Moreover, for the GUTs with $M_{GUT}\ge 1.0\times 10^{16}$ GeV, we for the first time study the upper bounds on the gaugino and sfermion masses. We show that the GUTs with anomaly and gauge mediated supersymmetry breakings are well within the reaches of the future 100 TeV pp colliders such as the ${\mathrm{FCC}}_{\mathrm{hh}}$ and SppC, and the supersymmetric GUTs with gravity mediated supersymmetry breaking can be probed at the future 160 TeV pp collider.

   hep-phPLB(2021)·2 citations
2. 02*

   PDF in PDFs from Hadronic Tensor and LaMET

   Keh-Fei Liu🇺🇸

   We point out a problem of the phenomenological definition of the valence partons as the difference between the partons and antipartons in the context of the NNLO evolution equations. After demonstrating that the classification of the parton degrees of freedom (PDF) of the parton distribution functions (PDFs) are the same in the QCD path-intergral formulations of the hadronic tensor and the quasi-PDF with LaMET, we resolve the problem by showing that the proper definition of the valence should be in terms of those in the connected insertions only. We also prove that the strange partons appear as the disconnected sea in the nucleon.

   hep-phhep-latnucl-thPRD(2020)·23 citations
3. 03*

   Plasma dark matter and electronic recoil events in XENON1T

   Lei Zu🇨🇳 · R. Foot🇦🇺 · Yi-Zhong Fan🇨🇳 · Lei Feng🇨🇳

   Dark matter might be in the form of a dark plasma in the Milky Way halo. Specifically, we consider here a hidden sector consisting of a light `dark electron' and a much heavier `dark proton', each charged under an unbroken $U(1{)}^{\prime }$ gauge symmetry. These self-interacting dark sector particles can also interact with ordinary matter via the kinetic mixing interaction, and lead to a signal in dark matter direct detection experiments. Indeed, keV electron recoils can arise quite naturally in such models from dark electron scattering off loosely bound atomic electrons. Here we examine the recently reported XENON1T excess in the context of such a plasma dark matter model. We find that the observed excess can be explained if kinetic mixing is in the approximate range: $10^{-12}\lesssim ϵ\lesssim 10^{-10}$. The allowed parameter space is consistent with astrophysical and cosmological constraints and consistent also with other direct detection experiments.

   hep-phJCAP(2021)·11 citations
4. 04*

   Study of $a_0^0(980)$-$f_0(980)$ mixing from $a_0(1450)\to a_0^0(980)f_0(500)\to {\pi }^{+}{\pi }^{-}{f}_0(500)$

   Xiao-Dong Cheng🇨🇳 · Ru-Min Wang🇨🇳 · Yuan-Guo Xu🇨🇳

   The $a_0^0(980)-f_0(980)$ mixing is one of the most potential tools to learn about the nature of $a_0^0(980)$ and $f_0(980)$. Using the $f_0(980)$-$a_0^0(980)$ mixing intensity ${\xi }_{af}$ measured recently at BESIII, we calculate the the branching ratio of the the isospin violation decay $J/\psi \to \gamma {\eta }_c\to \gamma {\pi }^0{a}_0^0(1450)\to \gamma {\pi }^0{a}_0^0(980)f_0(500)\to \gamma {\pi }^0{f}_0(980)f_0(500)\to \gamma {\pi }^0{\pi }^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}$. The value of the branching ratio is found to be $O(10^{-6})$, which can be observed with $10^{10}$ $J/\psi$ events collected at BESIII. The narrow peak from the $f_0(980)$-$a_0^0(980)$ mixing in the ${\pi }^{+}{\pi }^{-}$ mass square spectrum can also be observed. In addition, we study the non-resonant decay $a_0^0(1450)\to f_0(980){\pi }^{+}{\pi }^{-}(\text{non-resonant})$, which is dominated by the $a_0^0(980)$-$f_0(980)$ mixing. We find that the non-resonant decay $a_0^0(1450)\to f_0(980){\pi }^{+}{\pi }^{-}$ and the decay $a_0^0(1450)\to f_0(980)f_0(500)$ can be combined to measure the mixing intensity ${\xi }_{af}$ in experiment. These decays are the perfect complement to the decay ${\chi }_{c1}\to f_0(980){\pi }^0\to {\pi }^{+}{\pi }^{-}{\pi }^0$ which had been observed at BESIII, the observations of them will make the measurement of the mixing intensity ${\xi }_{af}$ more precisely.

   hep-phPRD(2020)·7 citations
5. 05*

   Masses of doubly heavy tetraquarks $QQ\bar{n}\bar{q}$ with $J^P=1^{+}$

   Di Gao · Duojie Jia · Yan-Jun Sun

   We apply the method of QCD sum rules to study the doubly heavy tetraquark states $QQ\bar{q}\bar{n}$ with spin-parity $J^P=1^{+}$ and strangeness $S=0,-1$ using careful estimates of the Borel and threshold parameters involved. Masses of the doubly bottom and charmed tetraquarks with isospin $I=0,1/2,1$ are computed precisely via taking into account multifarious condensates up to dimension $10$. Comparing with the two-heavy meson thresholds, we find that all nonstrange doubly-bottom tetraquarks and a doubly-charmed tetraquarks associted with $J_3$ with $J^P=1^{+}$ are stable against strong decay into two bottom mesons while a doubly-charmed tetraquarks associated with current $J_2$ is unstable against strong decay. By the way, weak decay widths of the doubly bottom tetraquarks are also given.

   hep-phMod.Phys.Lett.A(2022)·30 citations
6. 06*

   The magnetic moment of $Z_c(3900)$ as an axial-vector molecular state

   Yong-Jiang Xu🇨🇳 · Yong-Lu Liu🇨🇳 · Ming-Qiu Huang🇨🇳

   In this paper, we tentatively assign $Z_c(3900)$ to be an axialvector molecular state, and calculate its magnetic moment using the QCD sum rule method in external weak electromagnetic field. Starting with the two-point correlation function in external electromagnetic field and expanding it in power of the electromagnetic interaction Hamiltonian, we extract the mass and pole residue of $Z_c(3900)$ state from the leading term in the expansion and the magnetic moment from the linear response to the external electromagnetic field. The numerical values are $m_{Z_c}=3.97\pm 0.12\text{mbox}GeV$ in agreement with the experimental value $m_{Z_c}^{exp}=3899.0\pm 3.6\pm 4.9\text{mbox}MeV$, ${\lambda }_{Z_c}=2.1\pm 0.4\times 10^{-2}\text{mbox}{GeV}^5$ and ${\mu }_{Z_c}=0.19_{-0.01}^{+0.04}{\mu }_N$.

   hep-phEPJC(2020)·13 citations
7. 07*

   Higgs decay to fermion pairs at NLO in SMEFT

   Jonathan M. Cullen (Durham U., IPPP)🇬🇧 · Benjamin D. Pecjak (Durham U., IPPP)🇬🇧

   The calculation of next-to-leading order (NLO) perturbative corrections at fixed operator dimension in Standard Model Effective Field Theory (SMEFT) has been a topic of much recent interest. In this paper we obtain the NLO corrections from dimension-6 operators to the Higgs boson decays $h\to f\bar{f}$, where the fermions $f\in \{\mu ,\tau ,c\}$. This extends previous results for $h\to b\bar{b}$ to all phenomenologically relevant Higgs boson decays into fermions, and provides the basis for future precision analyses of these decays within effective field theory. We point out the benefits of studying ratios of decay rates into different fermions in SMEFT, the most surprising of which is enhanced sensitivity to anomalous $h\gamma \gamma$ and $hgg$ couplings induced by flavor-universal SMEFT operators, especially in scenarios where flavor-dependent Wilson coefficients are constrained by Minimal Flavor Violation.

   hep-phJHEP(2020)·32 citations
8. 08*

   Proton Decay in Supersymmetric $SU(4{)}_c\times SU(2{)}_L\times SU(2{)}_R$

   George Lazarides🇬🇷 · Mansoor Ur Rehman🇵🇰 · Qaisar Shafi🇺🇸

   We discuss proton decay in a recently proposed model of supersymmetric hybrid inflation based on the gauge symmetry $SU(4{)}_c\times SU(2{)}_L\times SU(2{)}_R$. A $U(1)R$ symmetry plays an essential role in realizing inflation as well as in eliminating some undesirable baryon number violating operators. Proton decay is primarily mediated by a variety of color triplets from chiral superfields, and it lies in the observable range for a range of intermediate scale masses for the triplets. The decay modes include $p\to e^{+}({\mu }^{+})+{\pi }^0$, $p\to \bar{\nu }+{\pi }^{+}$, $p\to K^0+e^{+}({\mu }^{+})$, and $p\to K^{+}+\bar{\nu }$, with a lifetime estimate of order $10^{34}-10^{36}$ yrs and accessible at Hyper-Kamiokande and future upgrades. The unification at the Grand Unified Theory (GUT) scale $M_{\mathrm{GUT}}$ ($\sim 10^{16}$ GeV) of the Minimal Supersymmetric Standard Model (MSSM) gauge couplings is briefly discussed.

   hep-phJHEP(2020)·11 citations
9. 09*

   Four lepton production and the accuracy of QED FSR

   Christian Gütschow🇬🇧 · Marek Schönherr🇬🇧

   We scrutinise the ability of the primary QED final-state resummation tools, combined with electroweak virtual corrections, to reproduce the exact next-to-leading order electroweak calculation in the four-charged-lepton final state. We further examine the dependence of the findings on the lepton-photon dressing-cone size as well as the resonance identification strategy. Overall we find excellent agreement with the fixed-order result, but partial differences not directly connected with resummation-induced higher-order effects at the few-percent level are observed in some cases, which are relevant for precision measurements.

   hep-phhep-exEPJC(2021)·15 citations
10. 10*

    Constraints on the charged currents in general neutrino interactions with sterile neutrinos

    Tong Li🇨🇳 · Xiao-Dong Ma🇹🇼 · Michael A. Schmidt🇦🇺

    In this work we investigate the implication of low-energy precision measurements on the quark-lepton charged currents in general neutrino interactions with sterile neutrinos in effective field theories. The physics in low-energy measurements is described by the low-energy effective field theory extended with sterile neutrinos (LNEFT) defined below the electroweak scale. We also take into account renormalization group running and match the LNEFT onto the Standard Model (SM) effective field theory with sterile neutrinos (SMNEFT) to constrain new physics (NP) above the electroweak scale. The most sensitive low-energy probes are from leptonic decays of pseudoscalar mesons and hadronic tau lepton decays in terms of precise decay branching fractions, the lepton flavor universality and the Cabibbo-Kobayashi-Maskawa (CKM) unitarity. We also consider other constraints including nuclear beta decay. The constraints on charged current operators are generally stronger than the ones for quark-neutrino neutral current operators. We find that the most stringent bounds on the NP scale of lepton-number-conserving and lepton-number-violating operators in SMNEFT are 74 (110) TeV and 9.8 (13) TeV, respectively, for the operators with down (strange) quark.

    hep-phJHEP(2020)·35 citations
11. 11*

    Modular $A_4$ symmetric inverse seesaw model with $SU(2{)}_L$ multiplet fields

    Takaaki Nomura🇰🇷 · Hiroshi Okada🇰🇷

    We propose an inverse seesaw model with large $SU(2{)}_L$ multiplets applying modular $A_4$ symmetry where $SU(2{)}_L$ quartet and septet fermions are introduced as triplets under the symmetry. The neutral components of the quartet contribute to mass matrix for inverse seesaw mechanism and interactions involving the septet induce Majorana mass terms of these extra fermions. Although there are several free parameters in the mass matrix we can obtain some predictions for observables in neutrino sector such as CP phases, sum of neutrino mass and effective mass for neutrinoless double beta decay, especially around fixed points of modulus motivated by string theories.

    hep-ph44 citations
12. 12*

    Some Properties of the $QQq$-Quark Potential in String Models

    Oleg Andreev🇷🇺

    We propose a string theory construction which allows us to study properties of the potential of two heavy quarks coupled to a light quark. In such a case, the potential is a function of separation between the heavy quarks. The results show the universality of the string tension and factorization at small separations expected from heavy quark-diquark symmetry. In addition, we make an estimate of the string breaking distance. With the parameter values we use, this distance is found to be almost the same as that for the heavy quark-antiquark potential. We also discuss the heavy quark-quark potential and its relation to Lipkin rule.

    hep-phhep-lathep-thnucl-thJHEP(2021)·17 citations
13. 13*

    Maximally self-interacting dark matter: models and predictions

    Ayuki Kamada🇰🇷 · Hee Jung Kim🇰🇷 · Takumi Kuwahara🇰🇷

    We study self-interacting dark matter (SIDM) scenarios, where the $s$-wave self-scattering cross section almost saturates the Unitarity bound. Such self-scattering cross sections are singly parameterized by the dark matter mass, and are featured by strong velocity dependence in a wide range of velocities. They may be indicated by observations of dark matter halos in a wide range of masses, from Milky Way's dwarf spheroidal galaxies to galaxy clusters. We pin down the model parameters that saturates the Unitarity bound in well-motivated SIDM models: the gauged $L_{\mu }-L_{\tau }$ model and composite asymmetric dark matter model. We discuss implications and predictions of such model parameters for cosmology like the $H_0$ tension and dark-matter direct-detection experiments, and particle phenomenology like the beam-dump experiments.

    hep-phastro-ph.COastro-ph.GAJHEP(2020)·35 citations
14. 14*

    Top-quark mass determination from t-channel single top production at the LHC

    Mei Sen Gao🇨🇳 · Shu Run Yuan🇨🇳 · Jun Gao🇨🇳

    We study the determination of the top-quark mass using leptonic observables in t-channel single top-quark production at the LHC. We demonstrate sensitivity of transverse momentum of the charged lepton on the input top-quark mass. We present predictions at next-to-next-to-leading order (NNLO) in QCD with narrow width approximation and structure function approach. Further corrections due to parton shower and hadronization, non-resonant and non-factorized contributions are discussed. To reduce impact of SM backgrounds we propose to use the charge weighted distribution for the measurement, i.e., differences between distributions of charged lepton with positive and negative charges. By modeling both signal and background processes, we found the projections for (HL-)LHC to be promising, with a total theoretical uncertainty on the extracted top-quark mass of about 1 $\sim$ 2 GeV.

    hep-phJHEP(2021)·4 citations
15. 15*

    YAM2: Yet another library for the $M_2$ variables using sequential quadratic programming

    Chan Beom Park🇰🇷

    The $M_2$ variables are devised to extend $M_{T2}$ by promoting transverse masses to Lorentz-invariant ones and making explicit use of on-shell mass relations. Unlike simple kinematic variables such as the invariant mass of visible particles, where the variable definitions directly provide how to calculate them, the calculation of the $M_2$ variables is undertaken by employing numerical algorithms. Essentially, the calculation of $M_2$ corresponds to solving a constrained minimization problem in mathematical optimization, and various numerical methods exist for the task. We find that the sequential quadratic programming method performs very well for the calculation of $M_2$, and its numerical performance is even better than the method implemented in the existing software package for $M_2$. As a consequence of our study, we have developed and released yet another software library, YAM2, for calculating the $M_2$ variables using several numerical algorithms.

    hep-phhep-exComput.Phys.Commun.(2021)·10 citations
16. 16*

    The Neutrino Magnetic Moment Portal: Cosmology, Astrophysics, and Direct Detection

    Vedran Brdar🇩🇪 · Admir Greljo🇨🇭 · Joachim Kopp🇨🇭 · Toby Opferkuch🇨🇭

    We revisit the physics of neutrino magnetic moments, focusing in particular on the case where the right-handed, or sterile, neutrinos are heavier (up to several MeV) than the left-handed Standard Model neutrinos. The discussion is centered around the idea of detecting an upscattering event mediated by a transition magnetic moment in a neutrino or dark matter experiment. Considering neutrinos from all known sources, as well as including all available data from XENON1T and Borexino, we derive the strongest up-to-date exclusion limits on the active-to-sterile neutrino transition magnetic moment. We then study complementary constraints from astrophysics and cosmology, performing, in particular, a thorough analysis of BBN. We find that these data sets scrutinize most of the relevant parameter space. Explaining the XENON1T excess with transition magnetic moments is marginally possible if conservative assumptions are adopted regarding the supernova 1987A and CMB constraints. Finally, we discuss model-building challenges that arise in scenarios that feature large magnetic moments while keeping neutrino masses well below 1 eV. We present a successful ultraviolet-complete model of this type based on TeV-scale leptoquarks, establishing links with muon magnetic moment, B physics anomalies, and collider searches at the LHC.

    hep-phJCAP(2021)·148 citations
17. 17*

    A quantum Monte Carlo based approach to intranuclear cascades

    Joshua Isaacson🇺🇸 · William I. Jay🇺🇸 · Alessandro Lovato🇺🇸 · Pedro A. N. Machado🇺🇸 · Noemi Rocco🇺🇸

    We propose a novel approach to intranuclear cascades which takes as input quantum MonteCarlo nuclear configurations and uses a semi-classical, impact-parameter based algorithm to modelthe propagation of protons and neutrons in the nuclear medium. We successfully compare oursimulations to available proton-carbon scattering data and nuclear-transparency measurements. Byanalyzing the dependence of the simulated observables upon the ingredients entering our intranuclearcascade algorithm, we provide a quantitative understanding of their impact. Particular emphasisis devoted to the role played by nuclear correlations, the Pauli exclusion principle, and interactionprobability distributions.

    hep-phhep-exnucl-thPRC(2021)·23 citations
18. 18*

    Accidental Symmetries in the 2HDMEFT

    Callum Birch-Sykes🇬🇧 · Neda Darvishi🇬🇧 · Yvonne Peters🇬🇧 · Apostolos Pilaftsis🇬🇧

    We construct accidentally symmetric potentials in the framework of Two Higgs Model Effective Field Theory (2HDMEFT) including higher-order operators of dimension 6 and dimension 8. Our construction is facilitated by an earlier developed technique based on prime invariants. In addition, we employ an alternative method that utilises the generators of each symmetry in the bi-adjoint representation and show how this method can be used to identify operators of any higher dimension. The accidentally symmetric 2HDMEFT potentials exhibit two classes of symmetries: (i) continuous symmetries and (ii) discrete symmetries. The number of continuous symmetries in the 2HDMEFT remains the same as in the 2HDM. However, the introduction of higher-order operators allows additional higher-order discrete symmetries, such as $Z_n$ and CP$n$. We classify the full list of the 17 accidental symmetries in the 2HDMEFT including dimension-6 and dimension-8 operators, and derive the relations that govern the theoretical parameters of the corresponding effective potentials.

    hep-phNPB(2020)·16 citations
19. 19*

    A dark clue to seesaw and leptogenesis in a pseudo-Dirac singlet doublet scenario with (non)standard cosmology

    Partha Konar🇮🇳 · Ananya Mukherjee🇮🇳 · Abhijit Kumar Saha🇮🇳 · Sudipta Show🇮🇳

    We propose an appealing alternative scenario of leptogenesis assisted by dark sector which leads to the baryon asymmetry of the Universe satisfying all theoretical and experimental constraints. The dark sector carries a non minimal set up of singlet doublet fermionic dark matter extended with copies of a real singlet scalar field. A small Majorana mass term for the singlet dark fermion, in addition to the typical Dirac term, provides the more favourable dark matter of pseudo-Dirac type, capable of escaping the direct search. Such a construction also offers a formidable scope to radiative generation of active neutrino masses. In the presence of a (non)standard thermal history of the Universe, we perform the detailed dark matter phenomenology adopting the suitable benchmark scenarios, consistent with direct detection and neutrino oscillations data. Besides, we have demonstrated that the singlet scalars can go through CP-violating out of equilibrium decay, producing an ample amount of lepton asymmetry. Such an asymmetry then gets converted into the observed baryon asymmetry of the Universe through the non-perturbative sphaleron processes owing to the presence of the alternative cosmological background considered here. Unconventional thermal history of the Universe can thus aspire to lend a critical role both in the context of dark matter as well as in realizing baryogenesis

    hep-phJHEP(2021)·42 citations
20. 20*

    Emergent 2HDM in LSS Little-Higgs: Musings from Flavor and Electroweak Physics

    Nilanjana Kumar🇮🇳 · Soumya Sadhukhan🇮🇳

    The low energy effective theory ($\sim$ TeV) of the little-Higgs model with $SU(6)/Sp(6)$, as proposed by Low, Skiba and Smith (LSS), exhibits a two-Higgs doublet model (2HDM) structure. The symmetry dictates interesting Yukawa patterns, translating to non-trivial fermion couplings with both of the Higgs doublets. The couplings of the scalars with the fermions can induce flavor changing neutral currents (FCNC), which get constraints from flavor physics observables such as BR$(B\to X_s\gamma )$, $B_s-{\bar{B}}_s$ mixing etc. The precision measurement of $Zb\bar{b}$ vertex, the top and Higgs mass along with other Higgs coupling measurements at the Large Hadron Collider (LHC) also enforce severe restrictions on the LSS model. Direct LHC search results of beyond the Standard Model (BSM) particles also impose bounds on the masses. We probe the LSS model in view of the above constraints through a random scan in the multi-dimensional parameter space. We observe, on contrary to the general 2HDM scenario, the emergent 2HDM from the LSS model is less constrained from the flavor data and the $Zb\bar{b}$ measurement but is severely constrained form the electroweak (EW) searches at the LHC. From the flavor data and $Zb\bar{b}$, we find that the charged Higgs mass is relaxed with $\tan \beta$ being restricted to $0.5-5$, whereas the charged Higgs mass is pushed to larger than 1 TeV along with $\tan \beta$ being further restricted to $<3$ when the LHC bounds are incorporated.

    hep-phPRD(2021)·2 citations
21. 21*

    Di-Higgs Blind Spots in Gravitational Wave Signals

    Alexandre Alves🇧🇷 · Dorival Gonçalves🇺🇸 · Tathagata Ghosh🇺🇸 · Huai-Ke Guo🇺🇸 · Kuver Sinha🇺🇸

    Conditions for strong first-order phase transition and generation of observable gravitational wave (GW) signals are very restrictive to the profile of the Higgs potential. Working in the minimal extension of the SM with a new gauge singlet real scalar, we show that the production of signals relevant for future GW experiments, such as LISA, can favor depleted resonant and non-resonant di-Higgs rates at colliders for phenomenologically relevant regimes of scalar mixing angles and masses for the heavy scalar. We perform a comprehensive study on the emergence of these di-Higgs blind spot configurations in GWs and also show that di-boson channels, $ZZ$ and $WW$, can restore the phenomenological complementarities between GW and collider experiments in these parameter space regimes.

    hep-phhep-exPLB(2021)·32 citations
22. 22*

    Breaking up the Proton: An Affair with Dark Forces

    Graham D. Kribs🇺🇸 · David McKeen🇨🇦 · Nirmal Raj🇨🇦

    Deep inelastic scattering of $e^{\pm }$ off protons is sensitive to contributions from "dark photon" exchange. Using HERA data fit to HERA's parton distribution functions, we obtain the model-independent bound $ϵ\lesssim 0.02$ on the kinetic mixing between hypercharge and the dark photon for dark photon masses $\lesssim 10$ GeV. This slightly improves on the bound obtained from electroweak precision observables. For higher masses the limit weakens monotonically; $ϵ\lesssim 1$ for a dark photon mass of $5$ TeV. Utilizing PDF sum rules, we demonstrate that the effects of the dark photon cannot be (trivially) absorbed into re-fit PDFs, and in fact lead to non-DGLAP (Bjorken $x_{\mathrm{B}}$-independent) scaling violations that could provide a smoking gun in data. The proposed $e^{\pm }p$ collider operating at $\sqrt{s}=1.3$ TeV, LHeC, is anticipated to accumulate $10^3$ times the luminosity of HERA, providing substantial improvements in probing the effects of a dark photon: sensitivity to $ϵ$ well below that probed by electroweak precision data is possible throughout virtually the entire dark photon mass range, as well as being able to probe to much higher dark photon masses, up to $100$ TeV.

    hep-phhep-exPRL(2021)·39 citations
23. 23*

    Heterodyne Broadband Detection of Axion Dark Matter

    Asher Berlin🇺🇸 · Raffaele Tito D'Agnolo🇫🇷 · Sebastian A. R. Ellis🇺🇸 · Kevin Zhou🇺🇸

    We propose a new broadband search strategy for ultralight axion dark matter that interacts with electromagnetism. An oscillating axion field induces transitions between two quasi-degenerate resonant modes of a superconducting cavity. In two broadband runs optimized for high and low masses, this setup can probe unexplored parameter space for axion-like particles covering fifteen orders of magnitude in mass, including astrophysically long-ranged fuzzy dark matter.

    hep-phastro-ph.COhep-exPRD(2021)·111 citations
24. 24*

    An experimental program with high duty-cycle polarized and unpolarized positron beams at Jefferson Lab

    A. Accardi🇺🇸 · A. Afanasev🇺🇸 · I. Albayrak🇹🇷 · S.F. Ali🇺🇸 · M. Amaryan🇺🇸 · J.R.M. Annand🇬🇧 · J. Arrington🇺🇸 · A. Asaturyan🇦🇲 · H. Atac🇺🇸 · H. Avakian🇺🇸 · T. Averett🇺🇸 · C. Ayerbe Gayoso🇺🇸 and 218 other authors

    Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic physics program at Jefferson Lab (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic structure of nucleons and nuclei, in both the elastic and deep-inelastic regimes. For instance, elastic scattering of polarized and unpolarized electrons and positrons from the nucleon enables a model independent determination of its electromagnetic form factors. Also, the deeply-virtual scattering of polarized and unpolarized electrons and positrons allows unambiguous separation of the different contributions to the cross section of the lepto-production of photons and of lepton-pairs, enabling an accurate determination of the nucleons and nuclei generalized parton distributions, and providing an access to the gravitational form factors. Furthermore, positron beams offer the possibility of alternative tests of the Standard Model of particle physics through the search of a dark photon, the precise measurement of electroweak couplings, and the investigation of charged lepton flavor violation. This document discusses the perspectives of an experimental program with high duty-cycle positron beams at JLab.

    ↳ nucl-exhep-exhep-phEPJA(2021)·64 citations
25. 25*

    Runaway potentials in warm inflation satisfying the swampland conjectures

    Suratna Das🇮🇳 · Rudnei O. Ramos🇧🇷

    The runaway potentials, which do not possess any critical points, are viable potentials which befit the recently proposed de Sitter swampland conjecture very well. In this work, we embed such potentials in the warm inflation scenario motivated by quantum field theory models generating a dissipation coefficient with a dependence cubic in the temperature. It is demonstrated that such models are able to remain in tune with the present observations and they can also satisfy all the three Swampland conjectures, namely the Swampland Distance conjecture, the de Sitter conjecture and the Transplackian Censorship Conjecture, simultaneously. These features make such models viable from the point of view of effective field theory models in quantum gravity and string theory, away from the Swampland.

    ↳ hep-thastro-ph.COgr-qchep-phPRD(2020)·57 citations
26. 26*

    Note on de Sitter vacua from perturbative and non-perturbative dynamics in type IIB/F-theory compactifications

    Vasileios Basiouris🇬🇷 · George K. Leontaris🇬🇷

    The properties of the effective scalar potential are studied in the framework of type IIB string theory, taking into account perturbative and non-perturbative corrections. The former modify the Kähler potential and include ${\alpha }^{\prime }$ and logarithmic corrections generated when intersecting D7 branes are part of the internal geometric configuration. The latter add exponentially suppressed Kähler moduli dependent terms to the fluxed superpotential. The possibility of partial elimination of such terms which may happen for particular choices of world fluxes is also taken into account. That being the case, a simple set up of three Kähler moduli is considered in the large volume regime, where only one of them is assumed to induce non-perturbative corrections. It is found that the shape of the F-term potential crucially depends on the parametric space associated with the perturbative sector and the volume modulus. De Sitter vacua can be obtained by implementing one of the standard mechanisms, i.e., either relying on D-terms related to $U(1)$ symmetries associated with the $D7$ branes, or introducing $\overline{D3}$ branes. In general it is observed that the combined effects of non-perturbative dynamics and the recently introduced logarithmic corrections lead to an effective scalar potential displaying interesting cosmological and phenomenological properties.

    ↳ hep-thhep-phPLB(2020)·19 citations
27. 27*

    Results of Dark Matter Search using the Full PandaX-II Exposure

    Qiuhong Wang🇨🇳 · Abdusalam Abdukerim🇨🇳 · Wei Chen🇨🇳 · Xun Chen🇨🇳 · Yunhua Chen🇨🇳 · Chen Cheng🇨🇳 · Xiangyi Cui🇨🇳 · Yingjie Fan🇨🇳 · Deqing Fang🇨🇳 · Changbo Fu🇨🇳 · Mengting Fu🇨🇳 · Lisheng Geng🇨🇳 and 53 other authors

    We report the dark matter search results obtained using the full 132 ton$\cdot$day exposure of the PandaX-II experiment, including all data from March 2016 to August 2018. No significant excess of events is identified above the expected background. Upper limits are set on the spin-independent dark matter-nucleon interactions. The lowest 90% confidence level exclusion on the spin-independent cross section is $2.2\times 10^{-46}$ cm${}^2$ at a WIMP mass of 30 GeV/$c^2$.

    ↳ astro-ph.COhep-exhep-phCPC(2020)·171 citations
28. 28*

    Quasinormal Modes and Stability of Firewalls

    Ryan McManus🇺🇸 · Emanuele Berti🇺🇸 · David E. Kaplan🇺🇸 · Surjeet Rajendran🇺🇸

    A solution to the black hole information problem requires propagation of information from the interior of the black hole to the exterior. Such propagation violates general relativity and could conceivably be accomplished through "firewall" models. Based on the existence of similar firewalls at the inner horizons of charged and rotating black holes, a model of a firewall was recently constructed where the exterior spacetime reduces to that of the Schwarzschild metric but with a dramatically different interior. We investigate the radial and nonradial polar stability of these objects. We first study the dynamics of the shell under spherically symmetric perturbations, and impose constraints on the firewall model parameters by requiring a subluminal speed of sound on the firewall. We show that the demands of stability and subluminality impose significant constraints on the internal parameters of the firewall, narrowing down the range of objects that could be used to create such a structure.

    ↳ gr-qchep-phhep-thPRD(2020)·5 citations
29. 29*

    Two-neutrino double-beta decay in pionless effective field theory from a Euclidean finite-volume correlation function

    Zohreh Davoudi🇺🇸 · Saurabh V. Kadam🇺🇸

    Two-neutrino double-beta decay of certain nuclear isotopes is one of the rarest Standard Model processes observed in nature. Its neutrinoless counterpart is an exotic lepton-number nonconserving process that is widely searched for to determine if the neutrinos are Majorana fermions. In order to connect the rate of these processes to the Standard Model and beyond the Standard Model interactions, it is essential that the corresponding nuclear matrix elements are constrained reliably from theory. Lattice quantum chromodynamics (LQCD) and low-energy effective field theories (EFTs) are expected to play an essential role in constraining the matrix element of the two-nucleon subprocess, which could in turn provide the input into ab initio nuclear-structure calculations in larger isotopes. Focusing on the two-neutrino process $nn\to pp(ee{\bar{\nu }}_e{\bar{\nu }}_e)$, the amplitude is constructed in this work in pionless EFT at next-to-leading order, demonstrating the emergence of a renormalization-scale independent amplitude and the absence of any new low-energy constant at this order beyond those present in the single-weak process. Most importantly, it is shown how a LQCD four-point correlation function in Euclidean and finite-volume spacetime can be used to constrain the Minkowski infinite-volume amplitude in the EFT. The same formalism is provided for the related single-weak process, which is an input to the double-$\beta$ decay formalism. The LQCD-EFT matching procedure outlined for the double-weak amplitude paves the road toward constraining the two-nucleon matrix element entering the neutrinoless double-beta decay amplitude with a light Majorana neutrino.

    ↳ hep-lathep-phnucl-thPRD(2020)·23 citations
30. 30*

    First experimental constraints on WIMP couplings in the effective field theory framework from CDEX

    Y. Wang · Z. Zeng · Q. Yue · L. T. Yang · K. J. Kang · Y. J. Li · M. Agartioglu · H. P. An · J. P. Chang · J. H. Chen · Y. H. Chen · J. P. Cheng and 76 other authors

    We present weakly interacting massive particles (WIMPs) search results performed using two approaches of effective field theory from the China Dark Matter Experiment (CDEX), based on the data from both CDEX-1B and CDEX-10 stages. In the nonrelativistic effective field theory approach, both time-integrated and annual modulation analyses were used to set new limits for the coupling of WIMP-nucleon effective operators at 90% confidence level (C.L.) and improve over the current bounds in the low $m_{\chi }$ region. In the chiral effective field theory approach, data from CDEX-10 were used to set an upper limit on WIMP-pion coupling at 90% C.L. We for the first time extended the limit to the $m_{\chi }<$ 6 GeV/$c^2$ region.

    ↳ hep-exhep-phphysics.ins-detSCPMA(2021)·28 citations
31. 31*

    Updated predictions for gravitational waves produced in a strongly supercooled phase transition

    John Ellis🇬🇧 · Marek Lewicki🇬🇧 · Ville Vaskonen🇬🇧

    We update predictions for the gravitational wave (GW) signal from a strongly supercooled phase transition in an illustrative classically conformal U(1)${}_{B-L}$ model. We implement $\propto {\gamma }^2$ scaling of the friction on the bubble wall and update the estimates for the efficiency factors for GW production from bubble collisions and plasma-related sources. We take into account the fact that a small decay rate of the symmetry-breaking field may lead to brief matter-dominated era after the transition, as the field oscillates around its minimum before decaying. We find that a strong bubble collision signal occurs in a significant part of the parameter space, and that the modified redshift of the modes that re-enter the horizon during the matter-dominated period generates a characteristic tilted `plateau' in the spectrum. The GW spectrum in this model would be detectable in the low-frequency range, e.g., by LISA, and in the mid-frequency range, e.g., by AION/MAGIS and AEDGE, and in the high-frequency range by LIGO and ET. The peak frequency of the signal is limited from below by collider constraints on the mass of the U(1)${}_{B-L}$ gauge boson, while at high frequencies the slow decay of the scalar field and the resulting matter-dominated era diminishes the GW signal.

    ↳ astro-ph.COhep-phJCAP(2020)·196 citations
32. 32*

    Topological structure of Nambu monopole in Two Higgs doublet models -- Fiber bundle, Dirac's quantization and dyon --

    Minoru Eto🇯🇵 · Yu Hamada🇯🇵 · Muneto Nitta🇯🇵

    We find a topologically non-trivial structure of the Nambu monopole in two Higgs doublet model (2HDM), which is a magnetic monopole attached by two topologically stable $Z$ strings ($Z$ flux tubes) from two opposite sides. The structure is in sharp contrast to the topological triviality of the Nambu monopole in the standard model (SM), which is attached by a single non-topological $Z$ string. It is found that the Nambu monopole in 2HDM possesses the same fiber bundle structure with those of the `t Hooft-Polyakov monopole and the Wu-Yang description of the Dirac monopole, as a result of the fact that the electromagnetic gauge field is well-defined even inside the strings and is non-trivially fibered around the monopole, while the Nambu monopole in the SM is topologically trivial because electroweak gauge symmetry is restored at the core of the string. Consequently, the Nambu monopole in 2HDM can be regarded as an embedding of the 't Hooft-Polyakov monopole into the $SU(2{)}_W$ gauge symmetry, and the Dirac's quantization condition always holds, which is absent for the Nambu monopole in the SM. Furthermore, we construct a dyon configuration attached with the two strings.

    ↳ hep-thhep-phPRD(2020)·18 citations
33. 33*

    Klein-Nishina effect and the cosmic ray electron spectrum

    Kun Fang🇨🇳 · Xiao-Jun Bi🇨🇳 · Su-Jie Lin🇨🇳 · Qiang Yuan🇨🇳

    Radiative energy losses are very important in regulating the cosmic ray electron and/or positron (CRE) spectrum during their propagation in the Milky Way. Particularly, the Klein-Nishina (KN) effect of the inverse Compton scattering (ICS) results in less efficient energy losses of high-energy electrons, which is expected to leave imprints on the propagated electron spectrum. It has been proposed that the hardening of CRE spectra around 50 GeV observed by Fermi-LAT, AMS-02, and DAMPE could be due to the KN effect. We show in this work that the transition from the Thomson regime to the KN regime of the ICS is actually quite smooth compared with the approximate treatment adopted in some previous works. As a result, the observed spectral hardening of CREs cannot be explained by the KN effect. It means that an additional hardening of the primary electrons spectrum is needed. We also provide a parameterized form for the accurate calculation of the ICS energy-loss rate in a wide energy range.

    ↳ astro-ph.HEhep-phChin.Phys.Lett.(2021)·45 citations
34. 34*

    Low mass strange stars and the compact star 1E1207.4-5209 in the Field Correlator Method

    F. I. M Pereira🇧🇷

    We investigate the possible existence of anomalous mass defects in the low mass region of stellar sequences of strange stars. We employ the nonperturbative equation of state derived in the framework of the Field Correlator Method to describe the hydrostatic equilibrium of the strange matter. The large distance static $Q\bar{Q}$ potential $V_1$ and the gluon condensate $G_2$ are the main parameters of the model. We use the surface gravitational redshift measurements as a probe to determine the ratio $(\mathcal{P}/\mathcal{E}{)}_C$ at the center of strange stars. For $V_1=0$ and $G_2\text{gappr}0.035{\mathrm{GeV}}^4$\,, we show that $(\mathcal{P}/\mathcal{E}{)}_C\simeq 0.262$ and the corresponding redshift $z_S\simeq 0.47$ are limiting values, at the maximum mass of the highest mass stellar sequence. As a direct application of our study, we try to determine the values of $V_1$ and $G_2$ from astrophysical observations of the compact star 1E\,1207.4-5209. Due to the uncertainties in the surface redshift determination, we made two attempts to obtain the model parameters. Our findings show that $(\mathcal{P}/\mathcal{E}{)}_C=0.073_{+0.024}^{+0.029}$\, at 68\% confidence, $V_1=0.44\pm 0.10$\,GeV at 90\% confidence and $G_2=0.008\pm 0.001{\mathrm{GeV}}^4$ at 95\% confidence \, in the first attempt; and $(\mathcal{P}/\mathcal{E}{)}_C=0.073_{+0.024}^{+0.029}=0.087\pm 0.028$\, at 71\% confidence, $V_1=0.43\pm 0.085$\,GeV at 94\% confidence and $G_2=0.0093\pm 0.00092{\mathrm{GeV}}^4$ at 94\% confidence in the second attempt. These values of $V_1$ and $G_2$ are in reasonable agreement with the lattice and QCD sum rules calculations. As a consequence of the high values of $V_1$ and $G_2$, the anomalous mass defects of 1E\,1207.4-5209 are $|{\Delta }_{2}M|\simeq 2.56\times 10^{53}$\,erg\, in the first attempt and $|{\Delta }_{2}M|\simeq 2.94\times 10^{53}$\,erg\, in the second attempt.

    ↳ nucl-thastro-ph.SRhep-lathep-phPRD(2021)·0 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.