Fri·Sep 18, 2020Friday·September 18, 2020

1. 01*

   Direct Detection Limits on Heavy Dark Matter

   Michael Clark🇺🇸 · Amanda Depoian🇺🇸 · Bahaa Elshimy🇺🇸 · Abigail Kopec🇺🇸 · Rafael F. Lang🇺🇸 · Shengchao Li · Juehang Qin🇺🇸

   Multiply-interacting massive particles (MIMPs) are heavy (>10^10 GeV/c^2) dark matter particles that interact strongly with regular matter, but may have evaded detection due to the low number density required to make up the local dark matter halo. These particles could leave track-like signatures in current experiments, similar to lightly-ionizing particles. We show that previously calculated limits from the MAJORANA Demonstrator on the flux of lightly-ionizing particles can be used to exclude MIMP dark matter parameter space up to a mass of 10^15 GeV/c^2. We also calculate limits from the standard XENON1T analysis in this high-mass regime, properly taking into account flux limitations and multi-scatter effects. Finally, we show that a dedicated MIMP analysis using the XENON1T dark matter search could probe unexplored parameter space up to masses of 10^18 GeV/c^2.

   hep-phhep-exPRD(2020)·48 citations
2. 02*

   Gravitational form-factors of the $\pi$ and $K$ mesons in QCD sum rules

   T. M. Aliev · K. Şimşek

   Taking into account only the quark part of the energy-momentum tensor, the gravitational form-factors of the $\pi$ and $K$ mesons are calculated within the light-cone sum rules method using the distribution amplitudes of these pseudoscalar mesons. The $Q^2$-dependence of the relevant form-factors are obtained. Moreover, the mean square mass radii of $\pi$ and $K$ mesons are calculated and we find that $\sqrt{⟨r_{\pi }^2⟩}=0.31\mathrm{fm}$ and $\sqrt{⟨r_K^2⟩}=0.24\mathrm{fm}$, respectively. We compare our results for gravitational form-factors with the existing literature results. We obtain that our results on $\sqrt{⟨r_{\pi }^2⟩}$ are in good agreement with the predictions of NJL model, AdS/QCD model, and other models as well as with the existing experimental data.

   hep-phPRD(2021)·10 citations
3. 03*

   Calculation of Feynman loop integration and phase-space integration via auxiliary mass flow

   Xiao Liu🇨🇳 · Yan-Qing Ma🇨🇳 · Wei Tao🇨🇳 · Peng Zhang🇨🇳

   We extend the auxiliary-mass-flow (AMF) method originally developed for Feynman loop integration to calculate integrals involving also phase-space integration. Flow of the auxiliary mass from the boundary ($\infty$) to the physical point ($0^{+}$) is obtained by numerically solving differential equations with respective to the auxiliary mass. For problems with two or more kinematical invariants, the AMF method can be combined with traditional differential equation method by providing systematical boundary conditions and highly nontrivial self-consistent check. The method is described in detail with a pedagogical example of $e^{+}{e}^{-}\to {\gamma }^{\ast }\to t\bar{t}+X$ at NNLO. We show that the AMF method can systematically and efficiently calculate integrals to high precision.

   hep-phCPC(2021)·80 citations
4. 04*

   Effects of $CP$-violating internucleon interactions in paramagnetic molecules

   V. V. Flambaum🇦🇺 · I. B. Samsonov🇦🇺 · H. B. Tran Tan🇦🇺

   We demonstrate that electron electric dipole moment experiments with molecules in paramagnetic state are sensitive to $P,T$-violating nuclear forces and other $CP$-violating parameters in the hadronic sector. These experiments, in particular, measure the coupling constant $C_{SP}$ of the $CP$-odd contact semileptonic interaction. We establish relations between $C_{SP}$ and different $CP$-violating hadronic parameters including strength constants of the $CP$-odd nuclear potentials, $CP$-odd pion-nucleon interactions, quark-chromo EDM and QCD vacuum angle. These relations allow us to find limits on various $CP$-odd hadronic parameters.

   hep-phnucl-thphysics.atom-phPRD(2020)·11 citations
5. 05*

   Path integral of neutrino oscillations

   Kazuo Fujikawa🇯🇵

   We propose an idea of the constrained Feynman amplitude for the scattering of the charged lepton and the virtual W-boson, $l_{\beta }+W_{\rho }\to l_{\alpha }+W_{\lambda }$, from which the conventional Pontecorvo oscillation formula of relativistic neutrinos is readily obtained using plane waves for all the particles involved. In a path integral picture, the neutrino propagates forward in time between the production and detection vertices, which are constrained respectively on the 3-dimensional spacelike hypersurfaces separated by a macroscopic positive time $\tau$. The covariant Feynman amplitude is formally recovered if one sums over all possible values of $\tau$ (including negative $\tau$).

   hep-phhep-th3 citations
6. 06*

   Bounds on neutrino-scalar nonstandard interactions from big bang nucleosynthesis

   Jorge Venzor🇲🇽 · Abdel Pérez-Lorenzana🇲🇽 · Josue De-Santiago🇲🇽

   Coherent forward scattering processes by neutrino-scalar nonstandard interactions (SNSI) induce an effective neutrino mass. In the Early Universe, a large neutrino effective mass restricts the production of neutrinos. The SNSI effect is modulated by two effective couplings, these account for the coupling between neutrinos and electrons/positrons, $G_{\mathrm{eff}}$, and the neutrino self-interaction, $G_{\mathrm{S}}$. These parameters are directly related to the effective number of relativistic species and non-zero values imply a smaller than expected $N_{\mathrm{eff}}$. We employ big bang nucleosynthesis to constraint the SNSI effect. We find that $G_{\mathrm{eff}}<1.2$ MeV${}^{-2}$ and $G_{\mathrm{S}}<2.0\times 10^7$ MeV${}^{-2}$ at 68\% CL. For a scalar mass in the range $10^{-15}\mathrm{eV}\lesssim m_{\varphi }\lesssim 10^{-5}\mathrm{eV}$, our neutrino-scalar coupling constraint is more restrictive than any previous result.

   hep-phastro-ph.COPRD(2021)·55 citations
7. 07*

   First NNLO fragmentation functions of $K_S^0$ and $\Lambda /\bar{\Lambda }$ and their uncertainties in the presence of hadron mass corrections

   Maryam Soleymaninia🇮🇷 · Hamed Abdolmaleki🇮🇷 · Hamzeh Khanpour🇮🇷

   The current paper presents a determination of $K_S^0$ and $\Lambda /\bar{\Lambda }$ fragmentation functions (FFs) from QCD analysis of single-inclusive electron-positron annihilation process (SIA). Our FFs determinations are performed at next-to-leading order (NLO), and for the first time, at next-to-next-to-leading order (NNLO) accuracy in perturbative Quantum Chromodynamics (pQCD) which is designated as {\tt SAK20} FFs. Each of these FFs is accompanied by their uncertainties which are determined using the `Hessian' method. Considering the hadron mass corrections, we clearly investigate the reliability of our results upon the inclusion of higher-order QCD correction. We provide comparisons of {\tt SAK20} FFs set with the available analysis from another group, finding in general a reasonable agreement, and also considerable differences. In order to judge the fit quality, our theoretical predictions are compared with the analyzed SIA datasets. {\tt SAK20} FFs at NLO and NNLO accuracy along with their uncertainties are made available in the standard {\tt LHAPDF} format in order to use for predictions of present and future measurements in high-energy collisions such as LHC and RHIC.

   hep-phhep-exPRD(2020)·8 citations
8. 08*

   Two-photon exchange effects in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ at small $\sqrt{s}$

   Zhong-Hua Zhao🇨🇳 · Hui-Yun Cao🇨🇳 · Hai-Qing Zhou🇨🇳

   In this work, the two-photon-exchange (TPE) effects in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ at small $\sqrt{s}$ are discussed within a hadronic model. In the limit $m_e\to 0$, the TPE contribution to the amplitude can be described by one scalar function ${\overline{c}}_1^{(2\gamma )}$. The ratio between this function and the corresponding contribution in one-photon exchange $c_1^{(1\gamma )}$ reflects all the information of the TPE corrections. The numerical results on this ratio are presented and an artificial function is used to fit the numerical results. The latter can be used conveniently in the further experimental data analysis. The numerical results show the asymmetry of the differential cross sections in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ is about $-4\%$ at $\sqrt{s}\sim 0.7$ GeV.

   hep-phnucl-exnucl-thPRC(2020)·1 citation
9. 09*

   Large-P_T inclusive photoproduction of J/psi in electron-proton collisions at HERA and the EIC

   Carlo Flore🇫🇷 · Jean-Philippe Lansberg🇫🇷 · Hua-Sheng Shao🇫🇷 · Yelyzaveta Yedelkina🇫🇷

   We study the inclusive J/psi production at large transverse momenta at lepton-hadron colliders in the limit when the exchange photon is quasi real, also referred to as photoproduction. Our computation includes the leading-P_T leading-v next-to-leading alpha_s corrections. In particular, we consider the contribution from J/psi plus another charm quark, by employing for the first time in quarkonium photoproduction the variable-flavour-number scheme. We also include a QED-induced contribution via an off-shell photon which remained ignored in the literature and which we show to be the leading contribution at high P_T within the reach of the EIC. In turn, we use our computation of J/psi+charm to demonstrate its observability at the future EIC and the EIC sensitivity to probe the non-perturbative charm content of the proton at high x.

   hep-phhep-exnucl-exnucl-thPLB(2020)·49 citations
10. 10*

    Explaining $g-2$ anomalies in two Higgs doublet model with vector-like leptons

    Eung Jin Chun🇰🇷 · Tanmoy Mondal🇰🇷

    We consider the two Higgs doublet model (2HDM) along with a generation of vector-like lepton doublet and singlet to explain the observed discrepancies in the electron and muon anomalous magnetic moments. The type-X (lepton-specific) 2HDM can allow a light pseudo-scalar which is known to explain the muon anomalous magnetic moment at two-loop. Such a light particle induces a sizable negative contribution to the electron anomalous magnetic moment at one-loop in the presence of vector-like leptons evading all the experimental constraints.

    hep-phJHEP(2020)·70 citations
11. 11*

    Central exclusive production of $W$ boson pairs in $pp$ collisions at the LHC in hadronic and semi-leptonic final states

    C. Baldenegro🇺🇸 · G. Biagi🇺🇸 · G. Legras🇺🇸 · C. Royon🇺🇸

    We present a phenomenology study on central exclusive production of $W^{+}{W}^{-}$ boson pairs in proton-proton collisions at the Large Hadron Collider at 14 TeV using the forward proton detectors, such as the ATLAS Forward Proton or the CMS-TOTEM Precision Proton Spectrometer detectors. Final states where at least one of the $W$ bosons decay hadronically in a large-radius jet are considered. The latter extends previous efforts that consider solely leptonic final states. A measurement of exclusive $W^{+}{W}^{-}$ also allows us to further constrain anomalous quartic gauge boson interactions between photons and $W$ bosons. Expected limits on anomalous quartic gauge couplings $a_{0,C}^W$ associated to dimension-six effective operators are derived for the hadronic, semi-leptonic, and leptonic final states. It is found that the couplings can be probed down to one-dimensional values of $a_0^W=3.7\times 10^{-7}$ GeV${}^{-2}$ and $a_C^W=9.2\times 10^{-7}$ GeV${}^{-2}$ at $95\%$ CL at an integrated luminosity of 300 fb${}^{-1}$ by combining all final states, compared to values of about $a_0^W=4\times 10^{-6}$ GeV${}^{-2}$ and $a_C^W=1\times 10^{-5}$ GeV${}^{-2}$ at 95\% CL expected for the leptonic channel alone.

    hep-phJHEP(2020)·21 citations
12. 12*

    Deciphering the mechanism of near-threshold $J/\psi$ photoproduction

    Meng-Lin Du🇩🇪 · Vadim Baru🇩🇪 · Feng-Kun Guo🇨🇳 · Christoph Hanhart🇩🇪 · Ulf-G. Meißner🇩🇪 · Alexey Nefediev🇷🇺 · Igor Strakovsky🇺🇸

    The photoproduction of the $J/\psi$ off the proton is believed to deepen our understanding of various physics issues. On the one hand, it is proposed to provide access to the origin of the proton mass, based on the QCD multipole expansion. On the other hand, it can be employed in a study of pentaquark states. The process is usually assumed to proceed through vector-meson dominance, that is the photon couples to a $J/\psi$ which rescatters with the proton to give the $J/\psi p$ final state. In this Letter, we provide a compelling hint for and propose measurements necessary to confirm a novel production mechanism via the ${\Lambda }_c{\bar{D}}^{(\ast )}$ intermediate states. In particular, there must be cusp structures at the ${\Lambda }_c{\bar{D}}^{(\ast )}$ thresholds in the energy dependence of the $J/\psi$ photoproduction cross section. The same mechanism also implies the $J/\psi$-nucleon scattering lengths of order 1 mfm. Given this, one expects only a minor contribution of charm quarks to the nucleon mass.

    hep-phhep-exhep-latnucl-ex+1EPJC(2020)·97 citations
13. 13*

    Perturbative QCD Evidence for Spin-2 Particles in the Di-$J/\psi$ Resonances

    Hong-Fei Zhang🇨🇳 · Yan-Qing Ma🇨🇳 · Wen-Long Sang🇨🇳

    We extend the nonrelativistic QCD framework to explore the nature of the newly discovered di-$J/\psi$ resonances. Assuming them as either molecule-like states or tetraquarks, we calculated their hadroproduction cross sections at the LHC. We find that the observed resonances are most likely spin-2 particles, and there should exist their spin-0 counterparts near these resonances. The ratio of production cross sections of the observed resonances to the latent spin-0 ones are also presented, which might help to distinguish molecule-like states from tetraquarks.

    hep-phhep-exSci.Bull.(2025)·88 citations
14. 14*

    Fragmentation production of fully-charmed tetraquarks at LHC

    Feng Feng🇨🇳 · Yingsheng Huang🇨🇳 · Yu Jia🇨🇳 · Wen-Long Sang🇨🇳 · Xiaonu Xiong🇨🇳 · Jia-Yue Zhang🇨🇳

    The $X(6900)$ resonance, very recently discovered in the double-$J/\psi$ channel at LHCb experiment, has spurred intensive interest in unravelling the nature of the fully charmed tetraquark state. The aim of this paper is to present a model-independent theoretical framework to study the inclusive production of this novel species of exotic hadrons, the resonances composed of four heavy quark (commonly referred to as $T_{4c}$), at large $p_T$ in hadron collision experiments. Appealing to asymptotic freedom and the fact $m_c\gg {\Lambda }_{\mathrm{QCD}}$, we propose that the nonpertubative yet universal gluon-to-$T_{4c}$ fragmentation function, can be decomposed into the product of the perturbatively calculable short-distance coefficient and the long-distance NRQCD matrix elements. We compute the short-distance coefficient at lowest-order in ${\alpha }_s$ and velocity expansion. Adopting the diquark ansatz to roughly estimate those not-yet-known NRQCD matrix elements, together with the standard QCD factorization theorem, we predict the differential production rates for the $T_{4c/4b}(0^{++})$ and $T_{4c/4b}(2^{++})$ at large $p_T$ in $pp$ collision, which eagerly awaits the confrontation with the future LHC experiments.

    hep-phhep-exPRD(2022)·85 citations
15. 15*

    Effects of neutrino magnetic moment and charge radius constraints and medium modifications of the nucleon form factors on the neutrino mean free path in dense matter

    Parada T.P. Hutauruk🇰🇷 · A. Sulaksono🇮🇩 · K. Tsushima🇧🇷

    Effects of neutrino charge radius and magnetic moment constraints obtained from the astrophysical observations and reactor experiments, as well as in-medium modifications of the weak and electromagnetic nucleon form factors of the matter on the neutrino electroweak interaction with dense matter, are estimated. We use a relativistic mean-field model for the in-medium effective nucleon mass and quark-meson coupling model for nucleon form factors. We analyze the neutrino scattering cross section and mean free path in cold nuclear matter. We find that the increase of the cross section relative to that without neutrino form factors results in the decrease of the neutrino mean free path when neutrino form factors and the in-medium modifications of the nucleon weak and electromagnetic form factors are simultaneously considered. The quenching of the neutrino mean free path is evaluated to be about 12-58\% for the values of ${\mu }_{\nu }=3\times 10^{-12}{\mu }_B$ and $R_{\nu }=3.5\times 10^{-5}{\text{MeV}}^{-1}$ compared with that obtained for the ${\mu }_{\nu }=0$ and $R_{\nu }=0$. The decrease of the neutrino mean free path is expected to decelerate the cooling of neutron stars. Each contribution of the neutrino form factors to the neutrino mean free path is discussed.

    hep-phastro-ph.HEnucl-thNPA(2022)·11 citations
16. 16*

    Scattering of axial gravitational wave pulses by monopole black holes and QNMs

    Alexander Gußmann🇺🇸

    We study scattering of short Gaussian pulses of axial gravitational waves by a black hole that has swallowed one or more global monopoles. We show how the response of the black hole to the impinging pulses depends both on the number of monopoles the black hole has swallowed and on the symmetry breaking scale of the model which gave rise to the monopoles. We determine the corresponding quasinormal modes that get excited by the impinging pulses and that get imprinted in the black hole's response to the pulses. Such modes are also expected to show up in various other dynamical processes such as the ringdown phase of a binary black hole merger in case at least one of the companion black holes of the binary has swallowed one or more global monopoles.

    ↳ gr-qchep-phhep-thClass.Quant.Grav.(2021)·3 citations
17. 17*

    NANOGrav Hints to Primordial Black Holes as Dark Matter

    V. De Luca🇨🇭 · G. Franciolini🇨🇭 · A. Riotto🇨🇭

    The NANOGrav Collaboration has recently published a strong evidence for a stochastic common-spectrum process that may be interpreted as a stochastic gravitational wave background. We show that such a signal can be explained by second-order gravitational waves produced during the formation of primordial black holes from the collapse of sizeable scalar perturbations generated during inflation. This possibility has two predictions: $i$) the primordial black holes may comprise the totality of the dark matter with the dominant contribution to their mass function falling in the range $(10^{-15}÷10^{-11})M_{\odot }$ and $ii$) the gravitational wave stochastic background will be seen as well by the LISA experiment.

    ↳ astro-ph.COgr-qchep-phPRL(2021)·337 citations
18. 18*

    Strong gravity effects of charged Q-clouds and inflating black holes

    Yves Brihaye🇧🇪 · Betti Hartmann🇧🇷

    In this paper, we re-examine charged Q-clouds around spherically symmetric, static black holes. In particular, we demonstrate that for fixed coupling constants two different branches of charged scalar clouds exist around Schwarzschild black holes. This had not been noticed previously. We find that the new solutions possess a "hard wall" at maximal possible gauge coupling. This wall separates the interior (containing the black hole horizon), in which the scalar field is trapped in the "false vacuum", from the "true vacuum" exterior. When taking back-reaction onto the space-time into account, we find that at maximal possible back reaction, the black hole solutions corresponding to these two branches either become extremal black holes with diverging scalar field derivative on the horizon or inflating black holes with a second, "cosmological" horizon which - outside this second horizon - correspond to extremal Reissner-Nordström black holes.

    ↳ gr-qchep-phhep-thClass.Quant.Grav.(2021)·12 citations
19. 19*

    Detailed $\beta$ spectrum calculations of ${}^{214}$Pb for new physics searches in liquid Xenon

    Leendert Hayen🇺🇸 · Stefano Simonucci🇮🇹 · Simone Taioli🇮🇹

    We present a critical assessment of the calculation and uncertainty of the ${}^{214}$Pb $\to$ ${}^{214}$Bi ground state to ground state $\beta$ decay, the dominant source of background in liquid Xenon dark matter detectors, down to below 1 keV. We consider contributions from atomic exchange effects, nuclear structure and radiative corrections. For each of these, we find changes much larger than previously estimated uncertainties and discuss shortcomings of the original calculation. Specifically, through the use of a self-consistent Dirac-Hartree-Fock-Slater calculation, we find that the atomic exchange effect increases the predicted flux by $10(3)\%$ at 1 keV relative to previous exchange calculations. Further, using a shell model calculation of the nuclear structure contribution to the shape factor, we find a strong disagreement with the allowed shape factor and discuss several sources of uncertainty. In the 1-200 keV window, the predicted flux is up to 20$\%$ lower. Finally, we discuss omissions and detector effects in previously used QED radiative corrections, and find small changes in the slope at the $\gtrsim 1\%$ MeV${}^{-1}$ level, up to $3\%$ in magnitude due to omissions in $\mathcal{O}(Z{\alpha }^2,Z^2{\alpha }^3)$ corrections and $3.5\%$ uncertainty from the neglect of as of yet unavailable higher-order contributions. Combined, these give rise to an increase of at least a factor 2 of the uncertainty in the 1-200 keV window. We comment on possible experimental schemes of measuring this and related transitions.

    ↳ nucl-thhep-exhep-phnucl-ex6 citations
20. 20*

    Causality Constraints in Large $N$ QCD Coupled to Gravity

    Jared Kaplan🇺🇸 · Sandipan Kundu🇺🇸

    Confining gauge theories contain glueballs and mesons with arbitrary spin, and these particles become metastable at large $N$. However, metastable higher spin particles, when coupled to gravity, are in conflict with causality. This tension can be avoided only if the gravitational interaction is accompanied by interactions involving other higher spin states well below the Planck scale $M_{\mathrm{pl}}$. These higher spin states can come from either the QCD sector or the gravity sector, but both these resolutions have some surprising implications. For example, QCD states can resolve the problem since there is a non-trivial mixing between the QCD sector and the gravity sector, requiring all particles to interact with glueballs at tree-level. If gravity sector states restore causality, any weakly coupled UV completion of the gravity-sector must have many stringy features, with an upper bound on the string scale. Under the assumption that gravity is weakly coupled, both scenarios imply that the theory has a stringy description above $N\gtrsim \frac{M_{\mathrm{pl}}}{{\Lambda }_{\mathrm{QCD}}}$, where ${\Lambda }_{\mathrm{QCD}}$ is the confinement scale.

    ↳ hep-thgr-qchep-phPRD(2021)·15 citations
21. 21*

    Understanding Q-Balls Beyond the Thin-Wall Limit

    Julian Heeck🇺🇸 · Arvind Rajaraman🇺🇸 · Rebecca Riley🇺🇸 · Christopher B. Verhaaren🇺🇸

    Complex scalar fields charged under a global U(1) symmetry can admit non-topological soliton configurations called Q-balls which are stable against decay into individual particles or smaller Q-balls. These Q-balls are interesting objects within quantum field theory, but are also of phenomenological interest in several cosmological and astrophysical contexts. The Q-ball profiles are determined by a nonlinear differential equation, and so generally require solution by numerical methods. In this work, we derive analytical approximations for the Q-ball profile in a polynomial potential and obtain simple expressions for the important Q-ball properties of charge, energy, and radius. These results improve significantly on the often-used thin-wall approximation and make it possible to describe Q-balls to excellent precision without having to solve the underlying differential equation.

    ↳ hep-thhep-phPRD(2021)·47 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.