Mon·Feb 17, 2020Monday·February 17, 2020

1. 01*

   Leading fermionic three-loop corrections to electroweak precision observables

   Lisong Chen🇺🇸 · Ayres Freitas🇺🇸

   Future electron-position colliders, such as CEPC and FCC-ee, have the capability to dramatically improve the experimental precision for W and Z-boson masses and couplings. This would enable indirect probes of physics beyond the Standard Model at multi-TeV scales. For this purpose, one must complement the experimental measurements with equally precise calculations for the theoretical predictions of these quantities within the Standard Model, including three-loop electroweak corrections. This article reports on the calculation of a subset of these corrections, stemming from diagrams with three closed fermion loops to the following quantities: the prediction of the W-boson mass from the Fermi constant, the effective weak mixing angle, and partial and total widths of the Z boson. The numerical size of these corrections is relatively modest, but non-negligible compared to the precision targets of future colliders. In passing, an error is identified in previous results for the two-loop corrections to the Z width, with a small yet non-zero numerical impact.

   hep-phJHEP(2020)·24 citations
2. 02*

   Transport properties in magnetized compact stars

   Toshitaka Tatsumi🇯🇵 · Hiroaki Abuki🇯🇵

   Transport properties of dense QCD matter is discussed. Using the Kubo formula for conductivity, we discuss some topological aspects of quark matter during chiral transition. The close relation to Weyl semimetal is pointed out and anomalous Hall effect is demonstrated to be possible there. In particular, it is shown that the spectral asymmetry of the quasi-particles plays an important role for the Hall conductivity in the magnetic field.

   hep-phnucl-thSymmetry(2020)·1 citation
3. 03*

   Probing $e\mu$ flavor-violating ALP at Belle II

   Motoi Endo🇯🇵 · Syuhei Iguro🇯🇵 · Teppei Kitahara🇮🇱

   Recently, it was pointed out that the electron and muon g-2 discrepancies can be explained simultaneously by a flavor-violating axion-like particle (ALP). We show that the parameter regions favored by the muon g-2 are already excluded by the muonium-antimuonium oscillation bound. In contrast, those for the electron g-2 can be consistent with this bound when the ALP is heavier than 1.5 GeV. We propose to search for a signature of the same-sign and same-flavor lepton pairs and the forward-backward muon asymmetry to test the model at the Belle II experiment.

   hep-phhep-exJHEP(2020)·78 citations
4. 04*

   Electromagnetic transition form factors, $E2/M1$ and $C2/M1$ ratios of the baryon decuplet

   June-Young Kim🇩🇪 · Hyun-Chul Kim🇰🇷

   We investigate the electromagnetic transition form factors of the baryon decuplet to the baryon octet, based on the self-consistent SU(3) chiral quark-soliton model, taking into account the effects of explicit breaking of flavor SU(3) symmetry. We emphasize the $Q^2$ dependence of the electromagnetic $N\to \Delta$ transition form factors and the ratios of $E2/M1$ and $C2/M1$ in comparison with the experimental and empirical data. In order to compare the present results of the electromagnetic transition form factors of the $N\to \Delta$ with those from lattice QCD, we evaluate the form factors with the pion mass deviated from its physical value. The results of the $E2/M1$ and $C2/M1$ ratios are in good agreement with the lattice data. We also present the results of the electromagnetic transition form factors for the decuplet to the octet transitions.

   hep-phhep-exhep-latnucl-exEPJC(2020)·14 citations
5. 05*

   On the generation of fermion condensate dynamically in $SU(2)$ gauge theory

   Rajdeep Basak🇮🇳 · Krishnendu Mukherjee🇮🇳

   Renormalized fermion condensate in $SU(2)$ gauge theory has been calculated in the background of static, stable gauge field configuration using field strength formalism. It is observed that the condensate attains a negative, minimum value at low energy.

   hep-ph0 citations
6. 06*

   Status of the WHIZARD generator for linear colliders

   Jürgen Reuter🇩🇪 · Simon Braß🇩🇪 · Pia Bredt🇩🇪 · Wolfgang Kilian🇩🇪 · Thorsten Ohl🇩🇪 · Vincent Rothe🇩🇪 · Pascal Stienemeier🇩🇪

   This summarizes the talk given at the LCWS 2019 conference in Sendai, Japan, on the progress of the WHIZARD event generator in terms of new physics features and technical improvements relevant for the physics programme of future lepton and especially linear colliders. It takes as a reference the version 2.8.2 released in October 2019, and also takes into account the development until version 2.8.3 to be released in February 2020.

   hep-phhep-ex4 citations
7. 07*

   Light by Light Scattering as a New Probe for Axions

   Soroush Shakeri🇮🇷 · David J. E. Marsh🇩🇪 · She-Sheng Xue🇮🇹

   We study the impact of virtual axions on the polarization of photons inside a cavity during the interaction of high-power laser pulses. A novel detection scheme for measuring the axion-induced ellipticity signal during the Light-by-Light (LBL) scattering process is investigated. We show that a momentum exchange between photons in a probe laser beam and a high-intensity target beam may lead to a resonance at the physical mass of the axion. Consequently, the resonant enhancement of vacuum birefringence gives rise to a large ellipticity signal. This signal enhancement can be applied in order to discriminate between the axion contribution to LBL scattering and the standard model contribution due to electron-positron pairs. The sensitivity of the scheme is studied for experimentally feasible probe light sources and ultrahigh intensity laser backgrounds. It is shown that this technique has the potential to probe the QCD axion in the mass range $10^{-2}\text{eV}\lesssim m_a\lesssim 1\text{eV}$. In this region the axion induced signal surpasses the standard model background.

   hep-phastro-ph.COastro-ph.IMhep-ex+111 citations
8. 08*

   Triply-charmed hexaquark states with the QCD sum rules

   Zhi-Gang Wang🇨🇳

   In this article, we construct the charmed-diquark-charmed-diquark-charmed-diquark type current to study the axialvector triply-charmed hexaquark state with the QCD sum rules in details. In calculations, we take the energy scale formula $\mu =\sqrt{M_H^2-(3{\mathbb{M}}_c{)}^2}$ to choose the pertinent energy scale of the QCD spectral density so as to enhance the pole contribution and improve the convergent behavior of the operator product expansion. If the spin-breaking effects are small for the triply-charmed hexaquark states, the ground state hexaquark states with $J^P=0^{+}$, $1^{+}$ and $2^{+}$ are estimated to have the masses about $5.8\mathrm{GeV}$ and narrow widths.

   hep-phInt.J.Mod.Phys.A(2020)·8 citations
9. 09*

   Below-threshold CP-odd Higgs boson search via A -> Z* h at the LHC

   E. Accomando🇬🇧 · M. Chapman🇬🇧 · A. Maury🇫🇷 · S. Moretti🇬🇧

   We study the process q q, g g -> A -> Z* h in a 2-Higgs Doublet Model Type-II where the mass of the CP-odd Higgs state A is lower than the rest mass of the Z and h particles (the latter being the Standard Model-like Higgs state), i.e., mA < mZ + mh = 215 GeV. This is a mass range which is not being currently tested by ATLAS and CMS in this channel, yet we show that there can be sensitivity to it already during Runs 2 and 3, assuming leptonic decays of the gauge boson and bottom-antibottom quark ones for the Higgs boson.

   hep-phhep-exPLB(2021)·10 citations
10. 10*

    Cornell potential in Kalb-Ramond scalar QED via Higgs mechanism

    Anais Smailagic🇮🇹 · Euro Spallucci🇮🇹

    In this letter we derive the Cornell confining potential in a theory of interacting Abelian gauge vector and massive Kalb-Ramond tensor. The Kalb-Ramond mass is instrumental to obtain the linear confining behavior of the potential at large distances. The same model can be described via interaction with Higgs fields, alternatively, providing mass to the vector, or to the tensor fields. In the first case, the photon acquires mass, while the tensor remains massless. The resulting interaction potential is a screened Coulomb one. In the second case, the photon remains massless while Kalb-Ramond tensor acquires mass and the resulting potential is of the Cornell type with the mass parameter determining the slope of the linear part.

    hep-phhep-thPLB(2020)·12 citations
11. 11*

    Boltzmann hierarchies for self-interacting warm dark matter scenarios

    Rafael Yunis🇮🇹 · Carlos R. Argüelles🇦🇷 · Diana López Nacir🇦🇷

    We provide a general framework for self-interacting warm dark matter (WDM) in cosmological perturbations, by deriving from first principles a Boltzmann hierarchy which retains certain independence from a particular interaction Lagrangian. We consider elastic interactions among the massive particles, and obtain a hierarchy which is more general than the ones usually obtained for non-relativistic (as for cold DM) or for ultra-relativistic (as for neutrinos) approximations. The more general momentum-dependent kernel integrals in the Boltzmann collision terms, are explicitly calculated for different field-mediator models, including examples of a scalar field (either massive or massless) or a massive vector field. As an application, we study the evolution of the interaction rate per particle under the relaxation time approximation, and assess when a given self-interaction is relevant in comparison with the Hubble expansion rate. Our framework aims to be a useful starting point to evaluate DM self-interaction effects in the linear power spectrum, necessary to then study its evolution all the way to non-linear stages of structure formation, where certain DM interactions were proven to be relevant.

    ↳ astro-ph.COhep-phJCAP(2020)·11 citations
12. 12*

    Production and measurement of $e^{+}{e}^{-}\to c\bar{c}$ signatures at the 250 GeV ILC

    A. Irles (1) · R. Pöeschl · (1) · F. Richard (1) (on behalf of the ILD concept group, (1) Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France)

    This document discusses for the first time the experimental prospects on the measurement of cross section and the forward-backward asymmetry in $e^{-}{e}^{+}\to c\bar{c}$ collisions at 250 GeV at the International Linear Collider operating polarised beams. The cross section will be normalised to the total hadronic cross section. We discuss the results for an analysis assuming the integrated luminosity of 2000 fb${}^{-1}$ foreseen in the baseline project. The measurement requires determining the charge of both jets identified as originated by a $c$-quark. The charge measurement is optimally performed using the precise micro-vertex detector of the detector ILD and the charged kaon identification provided by the $\frac{dE}{dx}$ information of its TPC. Thanks to the beam polarisation, we can separate the four independent chirality combinations of the electroweak couplings, enhancing in this way the sensitivity to new physics effects. We show that due to the unprecedented precision that will be achieved by the ILC for these observables, the ILC will be sensitive to the existence of beyond the standard model Randal Sundrum resonances of several tens of TeV.

    ↳ hep-exhep-ph12 citations
13. 13*

    A New Heavy Flavor Program for the Future Electron-Ion Collider

    Xuan Li🇺🇸 · Ivan Vitev🇺🇸 · Melynda Brooks🇺🇸 · Lukasz Cincio🇺🇸 · J. Matthew Durham🇺🇸 · Michael Graesser🇺🇸 · Ming X. Liu🇺🇸 · Astrid Morreale🇺🇸 · Duff Neill🇺🇸 · Cesar da Silva🇺🇸 · Walter E. Sondheim🇺🇸 · Boram Yoon🇺🇸

    The proposed high-energy and high-luminosity Electron-Ion Collider (EIC) will provide one of the cleanest environments to precisely determine the nuclear parton distribution functions (nPDFs) in a wide $x$-$Q^2$ range. Heavy flavor production at the EIC provides access to nPDFs in the poorly constrained high Bjorken-$x$ region, allows us to study the quark and gluon fragmentation processes, and constrains parton energy loss in cold nuclear matter. Scientists at the Los Alamos National Laboratory are developing a new physics program to study heavy flavor production, flavor tagged jets, and heavy flavor hadron-jet correlations in the nucleon/nucleus going direction at the future EIC. The proposed measurements will provide a unique way to explore the flavor dependent fragmentation functions and energy loss in a heavy nucleus. They will constrain the initial-state effects that are critical for the interpretation of previous and ongoing heavy ion measurements at the Relativistic Heavy Ion Collider and the Large Hadron Collider. We show an initial conceptual design of the proposed Forward Silicon Tracking (FST) detector at the EIC, which is essential to carry out the heavy flavor measurements. We further present initial feasibility studies/simulations of heavy flavor hadron reconstruction using the proposed FST.

    ↳ nucl-exhep-exhep-phnucl-thEPJ Web Conf.(2020)·23 citations
14. 14*

    Comparison of general-purpose events generators for particle fluence simulation in LHC environment

    Agnieszka Oblakowska-Mucha🇵🇱 · Tomasz Szumlak🇵🇱

    At the LHC era, the detector systems are operating at the harsh hadronic environment with the unprecedentedly high particle flux. Position sensitive silicon devices are usually positioned at the innermost regions of the experimental setups and must cope with highly non-uniform radiation fields. At the end of LHC Run II, fluence in silicon trackers reached 10${}^{15}$ n${}_{eq}$/cm${}^2$. Initial simulation studies predict that the maximal fluence for the HL-LHC may be up to two orders of magnitude higher than the one seen in LHC Run I and Run II. In this paper, two general-purpose physics events generators used for simulation of proton-proton collisions at LHC energies: Pythia 8.2 and DPMJET 3, are compared. Fluences obtained using these models, with the latest tuning to the LHC data, in detectors situated close to the point of proton-proton collisions are determined as well.

    ↳ hep-exhep-phEur.Phys.J.Plus(2021)·3 citations
15. 15*

    Sensitivity to invisible Higgs boson decays at CLIC

    Krzysztof Mekala🇵🇱 · Aleksander Filip Zarnecki🇵🇱 · Bohdan Grzadkowski🇵🇱 · Michal Iglicki🇵🇱

    We studied the possibility of measuring invisible Higgs boson decays at CLIC running at 380 GeV and 1.5 TeV. The analysis is based on the WHIZARD event generation and fast simulation of the CLIC detector response with DELPHES. We considered $e^{+}{e}^{-}$ background processes but also relevant $\gamma \gamma$ and $\gamma e^{\pm }$ interactions. The approach consisting of a two step analysis was used to optimize separation between signal and background processes. First, a set of preselection cuts was applied; then, multivariate analysis methods were employed to optimise the significance of observations. We estimated the expected limits on the invisible decays of the 125 GeV Higgs boson, as well as the cross section limits for production of an additional neutral Higgs-like scalar, assuming its invisible decays, as a function of its mass. Extracted model-independent branching ratio and cross section limits were then interpreted in the framework of the vector-fermion dark matter model to set limits on the mixing angle between the SM-like Higss boson and the new scalar of the "dark sector".

    ↳ hep-exhep-phEur.Phys.J.Plus(2021)·13 citations
16. 16*

    Is there an early Universe solution to Hubble tension?

    Chethan Krishnan🇮🇳 · Eoin Ó Colgáin🇰🇷 · Ruchika🇮🇳 · Anjan A. Sen🇮🇳 · M. M. Sheikh-Jabbari🇮🇷 · Tao Yang🇰🇷

    We consider a low redshift $(z<0.7)$ cosmological dataset comprising megamasers, cosmic chronometers, type Ia SNe and BAO, which we bin according to their redshift. For each bin, we read the value of $H_0$ by fitting directly to the flat $\Lambda$CDM model. Doing so, we find that $H_0$ descends with redshift, allowing one to fit a line with a \textit{non-zero} slope of statistical significance $2.1\sigma$. Our analysis rests on the use of cosmic chronometers to break a degeneracy in BAO data and it will be imperative to revisit this feature as data improves. Nevertheless, our results provide the first independent indication of the descending trend reported by the H0LiCOW collaboration. If substantiated going forward, early Universe solutions to the Hubble tension will struggle explaining this trend.

    ↳ astro-ph.COhep-phhep-thPRD(2020)·180 citations
17. 17*

    Robustness of principal component analysis on harmonic flow in heavy ion collisions

    Ziming Liu🇨🇳 · Arabinda Behera🇺🇸 · Huichao Song🇨🇳 · Jiangyong Jia🇺🇸

    The principal component analysis (PCA), a mathematical tool commonly used in statistics, has recently been employed to interpret the $p_T$-dependent fluctuations of harmonic flow $v_n$ in terms of leading and subleading flow modes in heavy ion collisions. Using simulated data from AMPT and HIJING models, we show that the PCA modes are not fixed, but depend on the choice of the particle weight and the $p_T$ range. Furthermore, the shape of the leading mode is affected by the presence of non-flow correlations, and fake subleading mode may arise from the mixing of non-flow correlations with leading flow mode with a magnitude that could be larger than the genuine subleading flow mode. Therefore, the meaning of PCA modes and their relations to physical leading and subleading flow modes associated initial state eccentricities need to be further clarified/validated in realistic model simulations.

    ↳ nucl-exhep-phPRC(2020)·12 citations
18. 18*

    Top Mass Shift Caused by the Recalibration of Flavor-Dependent Jet Energy Corrections in the D0 Lepton+Jets Top Mass Measurement

    Hannu Siikonen

    This paper introduces and applies a method for propagating changes in jet energy corrections into a D0 top quark mass measurement. It will serve as a source for the PRL presenting it's final results, and will be later published in a journal, or as a part of the author's PhD thesis. Motivation for the present measurement arises from the recalibration of the D0 flavor-dependent jet energy corrections. The recalibration was driven by the observation that the corrections for D0 Run IIb differ notably from those of Run IIa. The recalibration analysis was able to show that the Run IIb corrections should have resembled more those of Run IIa. The recalibrated jet energy corrections have an influence on the reconstructed top quarks through the jets that are produced in top quark decays. Hence, a change in the flavor-dependent jet energy corrections implies the need to revise the top mass measurement, performed by D0 in the lepton+jets channel. The D0 top mass average is almost completely determined by this measurement, and hence it has a direct impact on the top mass world average. A complete revision of the D0 top mass measurement is unlikely to occur, and hence this paper demonstrates the resulting top mass shift using a lighter methodology.

    ↳ hep-exhep-ph3 citations
19. 19*

    First study of $N_f=2+1+1$ lattice QCD with physical domain-wall quarks

    Ting-Wai Chiu🇹🇼

    Using 10-16 units of Nvidia DGX-1, we have generated the first gauge ensemble for $N_f=2+1+1$ lattice QCD with physical $(u/d,s,c)$ domain-wall quarks, on the $64^4$ lattice with lattice spacing $a\sim 0.064$ fm ($L>4$ fm, and $M_{\pi }L>3$). The salient feature of this gauge ensemble is that the chiral symmetry is preserved to a high precision and all topological sectors are sampled ergodically. In this paper, we present the first results of the topological susceptibility and the ground-state hadron mass spectra.

    ↳ hep-lathep-phPoS(2020)·6 citations
20. 20*

    Tensions in the dark: shedding light on Dark Matter-Dark Energy interactions

    Matteo Lucca🇧🇪 · Deanna C. Hooper🇧🇪

    The emergence of an increasingly strong tension between the Hubble rate inferred from early- and late-time observations has reinvigorated interest in nonstandard scenarios, with the aim of reconciling these measurements. One such model involves interactions between Dark Matter and Dark Energy. Here we consider a specific form of the coupling between these two fluids proportional to the Dark Energy energy density, which has been studied extensively in the literature and claimed to substantially alleviate the Hubble tension. We complement the work already discussed in several previous analyses and show that, once all relevant cosmological probes are included simultaneously, the value of the Hubble parameter in this model is $H_0=69.82_{-0.76}^{+0.63}$ km/(s Mpc), which reduces the Hubble tension to $2.5\sigma$. Furthermore, we also perform a statistical model comparison, finding a $\Delta {\chi }^2$ of $-2.15$ (corresponding to a significance of 1.5$\sigma$) with the inclusion of one additional free parameter, showing no clear preference for this model with respect to $\Lambda$CDM, which is further confirmed with an analysis of the Bayes ratio.

    ↳ astro-ph.COgr-qchep-phPRD(2020)·154 citations
21. 21*

    High energy scattering amplitude in the linearized gravitational theory

    Do Thu Ha🇻🇳

    The asymptotic behavior of the elastic scattering amplitude by the exchange of graviton between two scalar particles at high energies and fixed momentum transfers is reconsidered in the Logunov-Tavkhelidze equation in the linearized gravitational theory. The corrections to the eikonal approximation in the quasi-potential approach of relative order $1/p$ is developed with the principal contributions at high energy. The eikonal expression of scattering amplitude and the formal first correction are derived. The Yukawa potential is applied to discuss the results.

    ↳ hep-thhep-ph0 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.