Wed·May 1, 2019Wednesday·May 1, 2019

1. 01*

   Sensitivity bounds on heavy neutrino mixing $|U_{\mu N}{|}^2$ and $|U_{\tau N}{|}^2$ from LHCb upgrade

   Gorazd Cvetic🇨🇱 · C.S.Kim🇰🇷

   Decays of heavy pseudoscalar mesons $B$, $B_c$, $B_s$ and $D_s$ at LHCb upgrade are considered, which produce either two equal sign muons or taus. In addition, we consider the analogous decays with opposite sign muons or taus. All these decays are considered to be mediated by a heavy on-shell neutrino $N$. Such decays of $B$ mesons, if not detected, will give in general stringent upper bounds on the heavy-light mixing parameter $|U_{\mu N}{|}^2$ as a function of the neutrino mass $M_N\sim 1$ GeV, principally due to the large expected number of produced mesons $B$. While some of the decays of the other mentioned mesons are attractive due to a weaker CKM-suppression, the expected produced number of such mesons is significantly smaller that that of $B$'s; therefore, the sensitivity bounds from such decays are in general comparable or less restrictive. When $\tau$ pairs are produced, only two types of such decays are significant: $B^{\pm },B_c^{\pm }\to {\tau }^{\pm }{\tau }^{\pm }{\pi }^{\mp }$ (and ${\tau }^{\pm }{\tau }^{\mp }{\pi }^{\pm }$), giving us stringent upper bounds on $|U_{\tau N}{|}^2$; the other decays with a pair of $\tau$, such as $B^0\to D^{(\ast )-}{\tau }^{+}{\tau }^{+}{\pi }^{-}$ (and $D^{(\ast )-}{\tau }^{+}{\tau }^{-}{\pi }^{+}$), are prohibited or very suppressed by kinematics.

   hep-phPRD(2019)·28 citations
2. 02*

   Mapping the Kinematical Regimes of Semi-Inclusive Deep Inelastic Scattering

   M. Boglione🇮🇹 · A. Dotson🇺🇸 · L. Gamberg🇺🇸 · S. Gordon🇺🇸 · J. O. Gonzalez-Hernandez🇮🇹 · A. Prokudin🇺🇸 · T. C. Rogers🇺🇸 · N. Sato🇺🇸

   We construct a language for identifying kinematical regions of transversely differential semi-inclusive deep inelastic scattering cross sections with particular underlying partonic pictures, especially in regions of moderate to low $Q$ where sensitivity to kinematical effects outside the usual very high energy limit becomes non-trivial. The partonic pictures map to power law expansions whose leading contributions ultimately lead to well-known QCD factorization theorems. We propose methods for estimating the consistency of any particular region of overall hadronic kinematics with the kinematics of a given underlying partonic picture. The basic setup of kinematics of semi-inclusive deep inelastic scattering is also reviewed in some detail.

   hep-phnucl-exnucl-thJHEP(2019)·54 citations
3. 03*

   Triangle Singularity in the Production of $X(3872)$ and a Photon in $e^{+}{e}^{-}$ Annihilation

   Eric Braaten🇺🇸 · Li-Ping He🇺🇸 · Kevin Ingles🇺🇸

   If the $X(3872)$ is a weakly bound charm-meson molecule, it can be produced in $e^{+}{e}^{-}$ annihilation by the creation of $D^{\ast 0}{\bar{D}}^{\ast 0}$ from a virtual photon followed by the rescattering of the charm-meson pair into $X$ and a photon. A triangle singularity produces a narrow peak in the cross section for $e^{+}{e}^{-}\to X\gamma$ about 2.2 MeV above the $D^{\ast 0}{\bar{D}}^{\ast 0}$ threshold. We predict the normalized cross section in the region near the peak. The peak from the triangle singularity may be observable by the BESIII detector.

   hep-phPRD(2019)·32 citations
4. 04*

   Multiplicity dependence of strange and multi-strange hadrons in p$-$p, p$-$Pb and Pb$-$Pb collisions at LHC energies using Tsallis-Weibull Formalism

   Pritam Chakraborty🇮🇳 · Tulika Tripathy🇮🇳 · Subhadip Pal🇮🇳 · Sadhana Dash🇮🇳

   The transverse momentum ($p_T$) distribution of strange hadrons ($K_S^0$ and $\Lambda$) and multi-strange hadrons( $\Xi$ and $\Omega$) measured in p$-$p, p$-$Pb, and Pb$-$Pb collisions at LHC energies have been studied for different multiplicity classes using Tsallis-Weibull (or q$-$Weibull)formalism. The distribution describes the measured $p_T$ spectra for all multiplicity (or centrality)classes. The multiplicity dependence of the extracted parameters are studied for the mentioned collisions systems. The $\lambda$ parameter was observed to increase systematically with the collision multiplicity and follows a mass hierarchy for all collision system. This characteristic feature indicates that $\lambda$ can be associated to the strength of collectivity for heavy ion collisions. It can also be related to strength of dynamic effects such as multi-partonic interactions and color reconnections which mimic collectivity in smaller systems. The non-extensive $q$ parameter is found to be greater than one for all the particles suggesting that the strange particles are emitted from a source which is not fully equilibrated.

   hep-phnucl-thEPJA(2020)·2 citations
5. 05*

   B-physics anomalies: The bridge between R-parity violating Supersymmetry and flavoured Dark Matter

   Sokratis Trifinopoulos🇨🇭

   In recent years, significant experimental indications that point towards Lepton Flavour Universality violating effects in B-decays, involving $b\to c\tau \nu$ and $b\to s{\ell }^{+}{\ell }^{-}$ have been accumulated. A possible New Physics explanation can be sought within the framework of R-parity violating Supersymmetry, which contains the necessary ingredients to explain the anomalies via both leptoquark, tree-level exchange and one-loop diagrams involving purely leptonic interactions. In addition, an approximate $U(2{)}^2$ flavour symmetry, that respects gauge coupling unification, successfully controls the strength of these interactions. Nevertheless strong constraints from leptonic processes and $Z$ boson decays exclude most of the relevant parameter space at the $2\sigma$ level. Moreover, R-parity violation deprives Supersymmetry of its Dark Matter candidates. Motivated by these deficiencies, we introduce a new gauge singlet superfield, charged under the flavour symmetry and show that its third-generation, scalar component may participate in loop diagrams that alleviate the above-mentioned tensions, while at the same time reproduce the observed relic abundance. We obtain a solution to both anomalies that is also fully consistent with the rich Flavour and Dark Matter phenomenology. Finally, we assess the prospect to probe the model at future experiments.

   hep-phPRD(2019)·41 citations
6. 06*

   Bounds on Vacuum-Orthogonal Lorentz and CPT Violation from Radiative Corrections

   Brett Altschul🇺🇸

   Certain forms of Lorentz violation in the photon sector are difficult to bound directly, since they are "vacuum orthogonal," meaning they do not change the solutions of the equations of motion in vacuum. However, these very same terms have a unique tendency to contribute large radiative corrections to effects in other sectors. Making use of this, we set bounds on four previously unconstrained $d=5$ photon operators at the $10^{-25}$-$10^{-31}$ GeV${}^{-1}$ levels.

   hep-phPRD(2019)·6 citations
7. 07*

   Search for muon-philic new light gauge boson at Belle II

   Yongsoo Jho🇰🇷 · Youngjoon Kwon🇰🇷 · Seong Chan Park🇰🇷 · Po-Yan Tseng🇯🇵

   Motivated by the long-lasting $3.5\sigma$ discrepancy in the anomalous magnetic moment of muon, we consider a new muon-specific force mediated by a light gauge boson, $X$, with mass $m_X<2m_{\mu }$ and the coupling constant $g_X\sim (10^{-4},10^{-3})$. We show that the Belle~II experiment has a robust chance to probe such a light boson in $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}+X$ channel and cover the most interesting parameter space explaining the discrepancy with the planned target luminosity, $\int dt\mathcal{L}=50\mathrm{a}{\mathrm{b}}^{-1}$. The clean signal of muon-pair plus missing energy at Belle II can be a smoking gun for the new gauge boson. We expect that the (invisibly decaying) muon-philic light ($m_X\le 2m_{\mu }$) gauge boson can be probed down to $g_X\ge 1.5\times 10^{-4}(4.6\times 10^{-4},2.3\times 10^{-4})$ for 50 (1, 10) ab${}^{-1}$ search.

   hep-phJHEP(2019)·27 citations
8. 08*

   Implications of the dark axion portal for SHiP and FASER and the advantages of monophoton signals

   Patrick deNiverville🇰🇷 · Hye-Sung Lee🇰🇷

   We investigate the implications of the dark axion portal interaction, the axion-photon-dark photon vertex, for the future experiments SHiP and FASER. We also study the phenomenology of the combined vector portal (kinetic mixing of the photon and dark photon) and dark axion portal. The muon $g-2$ discrepancy is unfortunately not solved even with the two portals, but the low-energy beam dump experiments with monophoton detection capability can open new opportunities in light dark sector searches using the combined portals.

   hep-phPRD(2019)·31 citations
9. 09*

   A radiative neutrino mass model with hidden gauge symmetry inducing semi-annihilating dark matter

   Takaaki Nomura🇰🇷 · Hiroshi Okada🇰🇷

   We propose two-loop neutrino mass model with gauged hidden $U(1)$ symmetry, and discuss a Majorana type of dark matter candidate that has semi-annihilation processes in the relic density as well as lepton flavor violations and muon anomalous magnetic moment. Also, we demonstrate global analysis to satisfy neutrino oscillation data, lepton flavor violations, and relic density of dark matter candidate and show that semi-annihilation modes play a crucial role in finding observed relic density.

   hep-ph4 citations
10. 10*

    Constraining Affleck-Dine Leptogenesis after Thermal Inflation

    Seolhwa Kim🇰🇷 · Ewan D. Stewart🇰🇷

    Affleck-Dine leptogenesis after thermal inflation along the $L{H}_u$ direction requires $m_L^2+m_{H_u}^2<0$ up to the AD scale ($|L|\simeq |H_u|\sim 10^9$ GeV). We renormalised this condition from the AD scale to the soft supersymmetry breaking scale by solving the renormalisation group equations perturbatively in the Yukawa couplings to obtain a semi-analytic constraint on the soft supersymmetry breaking parameters. We also used a fully numerical method to renormalise the baryogenesis condition and constrained the Minimal Supersymmetric Cosmological Model using the resulting baryogenesis condition and other constraints, specifically, electroweak symmetry breaking, the observed Higgs mass, and the axino dark matter abundance.

    hep-phJCAP(2020)·1 citation
11. 11*

    Exact Correlators from Conformal Ward Identities in Momentum Space and Perturbative Realizations

    Claudio Corianò🇮🇹 · Matteo Maria Maglio🇮🇹 · Alessandro Tatullo🇮🇹 · Dimosthenis Theofilopoulos🇮🇹

    The general solution of the conformal Ward identities (CWI's) in momentum space, and their matching to perturbation theory, allows to uncover some specific characteristics of the breaking of conformal symmetry, induced by the anomaly. It allows to compare perturbative features of the 1-particle irreducible (1PI, nonlocal) anomaly action with the prediction of a similar (but exact) nonlocal action identified by the CWI's. The two predictions can be exactly matched at the level of 3-point functions. The analysis of the $TJJ$ and $TTT$ shows that both approaches - based either on 1PI or on the exact solutions of the CWI's - predict massless (dynamical) scalar exchanges in 3-point functions as the signature of the conformal anomaly. In a local formulation such 1PI actions exhibit a ghost in the spectrum which may induce ghost condensation. We also discuss alternative approaches, which take to Wess-Zumino forms of the action with an asymptotic dilaton, which should be considered phenomenological alternatives to the exact nonlocal action. If derived by a Weyl gauging, they also include a ghost in the spectrum. The two formulations, nonlocal and of WZ type, can be unified under the assumption that they describe the same anomaly phenomenon at two separate (UV/IR) ends of the renormalization group flow, possibly separated by a vacuum rearrangement at an intermediate scale. A similar analysis is presented for an $\mathcal{N}=1$ supersymmetric Yang-Mills theory. We comment on the possibile cosmological implications of such quasi Nambu-Goldstone modes as ultralight dilatons and axions.

    hep-phhep-thPoS(2019)·8 citations
12. 12*

    On searches for anomalous WWW interaction at the LHC

    B.A. Arbuzov🇷🇺 · I.V. Zaitsev🇷🇺

    The process $p+p\to W^{\pm }{W}^{+}{W}^{-}$ with lepton decays of $W$-bosons is shown to be promising for improving conditions for studies of parameter $\lambda$, which is the anomalous triple $W$-bosons interaction coupling constant.

    hep-phhep-ex0 citations
13. 13*

    Meson-meson scattering in two-dimensional QCD

    Guo-Ying Chen🇨🇳 · Yingsheng Huang🇨🇳 · Yu Jia🇨🇳 · Rui Yu🇨🇳

    We extend the formalism pioneered by Callan, Coote and Gross to investigate the meson-meson scattering within the framework of 't Hooft model, i.e., the two-dimensional QCD in the $N_c\to \infty$ limit. We derive the analytic expressions for various two-body meson-meson scattering amplitudes, concentrating on those quark diagrams which may be identified as the meson-meson contact interaction vertex in the context of the mesonic effective lagrangian in $1/N_c$ expansion. We also carry out a detailed numerical study for the meson-meson scattering for various quark flavors, and observe the near-threshold enhancement in some channels. This may be viewed as the hint of the existence of the tetra-quark state below two-meson threshold.

    hep-phhep-lathep-thnucl-th0 citations
14. 14*

    Can the ANITA anomalous events be due to new physics?

    James M. Cline🇨🇦 · Christian Gross🇮🇹 · Wei Xue🇨🇭

    The ANITA collaboration has observed two ultra-high-energy upgoing air shower events that cannot originate from Standard Model neutrinos that have traversed the Earth. Several beyond-the-standard-model physics scenarios have been proposed as explanations for these events. In this paper we present some general arguments making it challenging for new physics to explain the events. One exceptional class of models that could work is pointed out, in which metastable dark matter decays to a highly boosted lighter dark matter particle, that can interact in the Earth to produce the observed events.

    hep-phastro-ph.COastro-ph.HEPRD(2019)·38 citations
15. 15*

    Search for Light Weakly-Interacting-Massive-Particle Dark Matter by Annual Modulation Analysis with a Point-Contact Germanium Detector at the China Jinping Underground Laboratory

    L. T. Yang🇨🇳 · H. B. Li🇹🇼 · Q. Yue🇨🇳 · H. Ma🇨🇳 · K. J. Kang🇨🇳 · Y. J. Li🇨🇳 · H. T. Wong🇹🇼 · M. Agartioglu🇹🇼 · H. P. An🇨🇳 · J. P. Chang🇨🇳 · J. H. Chen🇹🇼 · Y. H. Chen🇨🇳 and 63 other authors

    We present results on light weakly interacting massive particle (WIMP) searches with annual modulation (AM) analysis on data from a 1-kg mass $p$-type point-contact germanium detector of the CDEX-1B experiment at the China Jinping Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2 yr span are analyzed with analysis threshold of 250 eVee. Limits on WIMP-nucleus ($\chi$-$N$) spin-independent cross sections as function of WIMP mass ($m_{\chi }$) at 90\% confidence level (C.L.) are derived using the dark matter halo model. Within the context of the standard halo model, the 90\% C.L. allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are excluded at $>$99.99\% and 98\% C.L., respectively. These results correspond to the best sensitivity at $m_{\chi }$$<$6$\mathrm{GeV}/c^2$ among WIMP AM measurements to date.

    ↳ hep-exhep-phphysics.ins-detPRL(2019)·64 citations
16. 16*

    Quantum Evaporation of Classical Breathers

    Jan Olle🇪🇸 · Oriol Pujolas🇪🇸 · Tanmay Vachaspati🇺🇸 · George Zahariade🇺🇸

    We apply the recently discovered classical-quantum correspondence (CQC) to study the quantum evaporation of breathers in an extended sine-Gordon model. We present numerical results for the decay rate of the breather as a function of the coupling strength in the model. This is a complete treatment of the backreaction of quantum radiation on the classical dynamics of oscillons.

    ↳ hep-thcond-mat.otherhep-phPRD(2019)·23 citations
17. 17*

    On the change of old neutron star masses with galactocentric distance

    Antonino Del Popolo🇮🇹 · Maksym Deliyergiyev🇵🇱 · Morgan Le Delliou🇨🇳 · Laura Tolos🇩🇪 · Fiorella Burgio🇮🇹

    We show that the pulsar mass depends on the environment, and that it decreases going towards the center of the Milky Way. This is due to two combined effects, the capture and accumulation of self-interacting, non-annihilating dark matter by pulsars, and the increase of the dark matter density going towards the galactic center. We show that mass decrease depends both on the density profile of dark matter, steeper profiles producing a faster and larger decrease of the pulsar mass, and on the strength of self-interaction. Once future observations will provide the pulsar mass in a dark matter rich environment, close to the galactic center, the present result will be able to put constraints on the characteristics of our Galaxy halo dark matter profile, on the nature of dark matter, namely on its annihilating or non-annihilating nature, on its strength of self-interaction, and on the particle mass.

    ↳ gr-qcastro-ph.HEhep-phnucl-thPhys.Dark Univ.(2020)·20 citations
18. 18*

    Violation of single-length scaling dynamics via spin vortices in an isolated spin-1 Bose gas

    C.-M. Schmied🇩🇪 · T. Gasenzer🇩🇪 · P. B. Blakie🇳🇿

    We consider the phase ordering dynamics of an isolated quasi-two-dimensional spin-1 Bose gas quenched into an easy-plane ferromagnetic phase. Preparing the initial system in an unmagnetized anti-ferromagnetic state the subsequent ordering involves both polar core and Mermin-Ho spin vortices, with the ratio between the different vortices controllable by the quench parameter. Ferromagnetic domain growth occurs as these vortices annihilate. The distinct dynamics of the two types of vortices means that the domain growth law is determined by two macroscopic length scales, violating the standard dynamic scaling hypothesis. Nevertheless we find that universality of the ordering process manifests in the decay laws for the spin vortices.

    ↳ cond-mat.quant-gashep-phPRA(2019)·20 citations
19. 19*

    Double-logarithms in N=8 supergravity: impact parameter description and mapping to 1-rooted ribbon graphs

    Agustín Sabio Vera🇪🇸

    The set of double-logarithmic (DL) contributions $(\alpha t{\ln }^{2}s{)}^n$ to the 4-graviton amplitude in $\mathcal{N}$$=$ 8 supergravity (SUGRA), with $\alpha$ being the gravitational coupling and $(s,t)$ the Mandelstam invariants, is studied in impact parameter ($\rho$) representation. This sector of the amplitude shows interesting properties which shed light on the nature of quantum corrections in gravity. Besides having a convergent behaviour as $s$ increases, which is not present in $\mathcal{N}$$<$ 4 SUGRA theories, there exists a critical line ${\rho }_c(s)$ above which the Born amplitude prevails. The short distance region $\rho <{\rho }_c(s)$ is dominated by the DL terms. As a consequence, when studied in terms of an eikonal approach in the forward limit, the scattering angle linked to the bending of the semiclassical trajectory of the graviton shows a transition from attractive gravity at large distances to a region at small $\rho$ characterized by a repulsive DL contribution to the gravitational potential due to the gravitino content of the theory. In the complex angular momentum plane, this DL high energy asymptotics is driven by the rightmost pole singularity of a parabolic cylinder function. The resummation of DL quantum corrections in $\mathcal{N}$$=$ 8 SUGRA can be understood in terms of the counting of 1-rooted maps on orientable surfaces.

    ↳ hep-thhep-phmath-phmath.MPJHEP(2019)·8 citations
20. 20*

    The Scikit-HEP Project

    Eduardo Rodrigues🇺🇸

    The Scikit-HEP project is a community-driven and community-oriented effort with the aim of providing Particle Physics at large with a Python scientific toolset containing core and common tools. The project builds on five pillars that embrace the major topics involved in a physicist's analysis work: datasets, data aggregations, modelling, simulation and visualisation. The vision is to build a user and developer community engaging collaboration across experiments, to emulate scikit-learn's unified interface with Astropy's embrace of third-party packages, and to improve discoverability of relevant tools.

    ↳ physics.comp-phhep-exhep-phEPJ Web Conf.(2019)·23 citations
21. 21*

    Gravitationally trapped axions on Earth

    Kyle Lawson🇨🇦 · Xunyu Liang🇨🇦 · Alexander Mead🇨🇦 · Md Shahriar Rahim Siddiqui🇨🇦 · Ludovic Van Waerbeke🇨🇦 · Ariel Zhitnitsky🇨🇦

    We advocate for the idea that there is a fundamentally new mechanism for axion production on Earth, as recently suggested in Fischer et al. (2018) and Liang & Zhitnitsky (2018). We specifically focus on production of axions within Earth, with low velocities such that they will be trapped in the gravitational field. Our computations are based on the so-called Axion Quark Nugget (AQN) dark matter model, which was originally invented to explain the similarity of the dark and visible cosmological matter densities. This occurs in the model irrespective of the axion mass $m_{\mathrm{a}}$ or initial misalignment angle ${\theta }_0$. Annihilation of antimatter AQNs with visible matter inevitably produce axions when AQNs hit Earth. The emission rate of axions with velocities below escape velocity is very tiny compared to the overall emission, however these axions will be accumulated over the 4.5 billion year life time of the Earth, which greatly enhances the discovery potential. We perform numerical simulations with a realistically modeled incoming AQN velocity and mass distribution, and explore how AQNs interact as they travel through the interior of the Earth. We use this to estimate the axion flux on the surface of the Earth, the velocity-spectral features of trapped axions, the typical annihilation pattern of AQN, and the density profile of the axion halo around the Earth. Knowledge of these properties is necessary to make predictions for the observability of trapped axions using CAST, ADMX, MADMAX, CULTASK, ORPHEUS, ARIADNE, CASPEr, ABRACADABRA, QUAX, DM Radio.

    ↳ astro-ph.COhep-phPRD(2019)·35 citations
22. 22*

    A safe CFT at large charge

    Domenico Orlando🇮🇹 · Susanne Reffert🇨🇭 · Francesco Sannino🇩🇰

    We apply the large-charge limit to the first known example of a four-dimensional gauge-Yukawa theory featuring an ultraviolet interacting fixed point in all couplings. We determine the energy of the ground state in presence of large fixed global charges and deduce the global symmetry breaking pattern. We show that the fermions decouple at low energy leaving behind a confining Yang-Mills theory and a characteristic spectrum of type I (relativistic) and type II (non-relativistic) Goldstone bosons. Armed with the knowledge acquired above we finally arrive at establishing the conformal dimensions of the theory as a triple expansion in the large-charge, the number of flavors and the controllably small inverse gauge coupling constant at the UV fixed point. Our results unveil a number of noteworthy properties of the low-energy spectrum, vacuum energy and conformal properties of the theory. They also allow us to derive a new consistency condition for the relative sizes of the couplings at the fixed point.

    ↳ hep-thhep-lathep-phJHEP(2019)·44 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.