Tue·Oct 19, 2021Tuesday·October 19, 2021

1. 01*

   Probing the Earth's Core using Atmospheric Neutrinos at INO

   Anil Kumar🇮🇳 · Sanjib Kumar Agarwalla🇮🇳

   The proposed 50 kt Iron Calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) aims to detect atmospheric muon neutrinos and antineutrinos separately in the multi-GeV range of energies and over a wide range of path lengths. While passing through the Earth, the upward-going neutrinos experience a density-dependent matter effect, which can be utilized to extract information about the internal structure of Earth. Since the Earth's matter effect modifies the neutrino oscillation patterns differently for neutrinos and antineutrinos, the capability of ICAL to distinguish ${\mu }^{-}$ and ${\mu }^{+}$ events plays an important role in observing this matter effect. Taking advantage of good angular resolution, ICAL would be able to observe about 331 ${\mu }^{-}$ and 146 ${\mu }^{+}$ events corresponding to the core-passing neutrinos and antineutrinos, respectively, in 10 years. We demonstrate for the first time that ICAL would be able to validate the presence of Earth's core by ruling out a two-layered profile consisting of only mantle and crust in fit with respect to the PREM profile in data with a median $\Delta {\chi }^2$ of 7.45 for normal mass ordering (NO) and 4.83 for inverted mass ordering (IO) using 500 kt$\cdot$yr exposure. If we do not use the charge identification capability of ICAL, these sensitivities deteriorate to a $\Delta {\chi }^2$ of 3.76 for NO and 1.59 for IO.

   hep-phphysics.ins-detPoS(2022)·0 citations
2. 02*

   Quark spin-orbit correlations in the pion meson in light-cone quark model

   Chentao Tan🇨🇳 · Zhun Lu🇨🇳

   We study the correlation between the quark spin and orbital angular momentum inside the pion meson. Similar to the case inside the nucleon, the longitudinal spin-orbit correlation $C_z^{q/\pi }$ in pion meson can be expressed in terms of the corresponding generalized parton distributions (GPDs) and generalized transverse momentum distributions (GTMDs). This provides new information about the spin structure of the pion. Using the wavefunctions of the pion in the light-cone quark model and the overlap representation for GPDs and GTMDs, we present the analytical results for the quark longitudinal spin-orbit correlation. We find that the GPD approach and the GTMD approach lead to the same results. The numerical results is also obtained, showing that the correlation in pion is anti-aligned. In addition, we compare $C_z^{q/\pi }$ from the GPD approach and the GTMD approach, with $x$ and the transverse momentum $k_T$ unintegrated.

   hep-phPRD(2022)·17 citations
3. 03*

   Improving Variational Autoencoders for New Physics Detection at the LHC with Normalizing Flows

   Pratik Jawahar🇨🇭 · Thea Aarrestad🇨🇭 · Nadezda Chernyavskaya🇨🇭 · Maurizio Pierini🇨🇭 · Kinga A. Wozniak🇨🇭 · Jennifer Ngadiuba🇺🇸 · Javier Duarte🇺🇸 · Steven Tsan🇺🇸

   We investigate how to improve new physics detection strategies exploiting variational autoencoders and normalizing flows for anomaly detection at the Large Hadron Collider. As a working example, we consider the DarkMachines challenge dataset. We show how different design choices (e.g., event representations, anomaly score definitions, network architectures) affect the result on specific benchmark new physics models. Once a baseline is established, we discuss how to improve the anomaly detection accuracy by exploiting normalizing flow layers in the latent space of the variational autoencoder.

   hep-phhep-exphysics.data-anFront.Big Data(2022)·40 citations
4. 04*

   The Dark $Z^{\prime }$ and Sterile Neutrinos Behind Current Anomalies

   A. Hammad🇰🇷 · Ahmed Rashed🇺🇸 · S. Moretti🇬🇧

   We show how, in the $B-L$ extension of the SM (BLSM) with an Inverse Seesaw (IS) mechanism for neutrino mass generation, a light $Z^{\prime }$ state with moderate couplings to SM objects, hence `dark' in its nature, can be associated, in conjunction with light sterile neutrinos, to some present day data anomalies, such as the anomalous magnetic moment of the muon as well as a possible signal indicating the existence of sterile neutrinos in neutrino beam experiments.

   hep-phPLB(2022)·22 citations
5. 05*

   Dineutrino modes probing lepton flavor violation

   Rigo Bause🇩🇪 · Hector Gisbert🇩🇪 · Marcel Golz🇩🇪 · Gudrun Hiller🇩🇪

   $SU(2{)}_L$-invariance links charged dilepton $\bar{q}{q}^{\prime }{\ell }^{+}{\ell }^{-}$ and dineutrino $\bar{q}{q}^{\prime }\bar{\nu }\nu$ couplings. This connection can be established using the Standard Model Effective Field Theory framework, and allows to perform complementary experimental tests of lepton universality and charged lepton flavor conservation with flavor-summed dineutrino observables. We present its phenomenological implications for the branching ratios of rare charm decays $c\to u\nu \bar{\nu }$ and rare $B$ decays $b\to s\bar{\nu }\nu$ decays.

   hep-phPoS(2022)·4 citations
6. 06*

   CP violation in the rare Higgs decays via exchange of on-shell almost degenerate Majorana neutrinos, $H\to {\nu }_k{N}_j\to {\nu }_k{\ell }^{-}U\bar{D}$ and $H\to {\nu }_k{N}_j\to {\nu }_k{\ell }^{+}\bar{U}D$

   Gorazd Cvetič (1)🇨🇱 · C. S. Kim (2)🇰🇷 · Jiberto Zamora-Saá (3) ((1) Universidad Técnica Federico Santa María, (2) Yonsei University, (3) Universidad Andres Bello)🇨🇱

   We investigate rare decays of Higgs via exchange of two almost degenerate heavy on-shell Majorana neutrinos $N_j$ ($j=1,2$): ${\Gamma }_{\pm }=\Gamma (h\to {\nu }_k{N}_j\to {\nu }_k{\ell }^{\pm }{\pi }^{\mp })$, and into the open quark channels ${\Gamma }_{\pm }=\Gamma (h\to {\nu }_k{N}_j\to {\nu }_k{\ell }^{\pm }UD)$, where $UD$ are two jets of open quarks ($\bar{U}D$, or $U\bar{D}$, where $U=u,c$ and $D=d,s$). The related CP violation asymmetry $A_{\mathrm{CP}}=({\Gamma }_{-}-{\Gamma }_{+})/({\Gamma }_{-}+{\Gamma }_{+})$ is studied in detail. We take into account the $N_1$-$N_2$ overlap and oscillation effects. We can see that for certain, presently acceptable, range of input parameters, such decays with open quark channels, and their asymmetries, could be detected in the International Linear Collider (ILC).

   hep-phJHEP(2022)·7 citations
7. 07*

   Nature of $X(2370)$

   Xiang Sun🇨🇳 · Ling-Yun Dai🇨🇳 · Shi-Qing Kuang🇨🇳 · Wen Qin🇨🇳 · A.P. Szczepaniak🇺🇸

   We address the nature of the $X(2370)$ resonance observed in the $J/\psi$ radiative decays, $J/\psi \to \gamma K^{+}{K}^{-}{\eta }^{\prime }$, $J/\psi \to \gamma K_S{K}_S{\eta }^{\prime }$ and $J/\psi \to \gamma {\pi }^{+}{\pi }^{-}{\eta }^{\prime }$. By studying the invariant mass spectra we confirm that decays of the $X(2370)$ into three pseudo-scalars are well described by an effective chiral Lagrangian. We extract the branching ratio of $J/\psi \to X(2370)\gamma$ and show that it is an order of magnitude larger compared to the glueball production rate predicted by lattice QCD. This indicates that $X(2370)$ is not likely to be a glueball candidate.

   hep-phnucl-thPRD(2022)·7 citations
8. 08*

   Revising inelastic dark matter direct detection by including the cosmic ray acceleration

   Jie-Cheng Feng🇨🇳 · Xian-Wei Kang🇨🇳 · Chih-Ting Lu🇰🇷 · Yue-Lin Sming Tsai🇨🇳 · Feng-Shou Zhang🇨🇳

   The null signal from collider and dark matter (DM) direct detector experiments makes the interaction between DM and visible matter too small to reproduce the correct relic density for many thermal DM models. The remaining parameter space indicates that two almost degenerated states in the dark sector, the inelastic DM scenario, can co-annihilate in the early universe to produce the correct relic density. Regarding the direct detection of the inelastic DM scenario, the virialized DM component from the nearby halo is nonrelativistic and not able to excite the DM ground state, even if the relevant couplings can be considerable. Thus, a DM with a large mass splitting can evade traditional virialized DM direct detection. In this study, we connect the concept of cosmic-ray accelerated DM in our Milky Way and the direct detection of inelastic scattering in underground detectors to explore spectra that result from several interaction types of the inelastic DM. We find that the mass splitting $\delta <\mathcal{O}(1\mathrm{MeV})$ can still be reachable for cosmic ray accelerated DM with mass range $1\mathrm{MeV}<m_{{\chi }_1}<100\mathrm{GeV}$ and sub-GeV light mediator using the latest PandaX-4T data, even though we conservatively use the astrophysical parameter (effective length) $D_{\mathrm{eff}}=1$ kpc.

   hep-phastro-ph.HEhep-exJHEP(2022)·39 citations
9. 09*

   Analysis of Bose-Einstein condensation times for self-interacting scalar dark matter

   Kay Kirkpatrick🇺🇸 · Anthony E. Mirasola🇺🇸 · Chanda Prescod-Weinstein🇺🇸

   We investigate the condensation time of self-interacting axion-like particles in a gravitational well, extending the prior work [arXiv:2007.07438] which showed that the Wigner formalism is a good analytic approach to describe a condensing scalar field. In the present work, we use this formalism to affirm that ${\varphi }^4$ self-interactions will take longer than necessary to support the time scales associated with structure formation, making gravity a necessary part of the process to bring axion dark matter into a solitonic form. Here we show that when the axions' virial velocity is taken into account, the time scale associated with self-interactions will scale as ${\lambda }^2$. This is consistent with recent numerical estimates, and it confirms that the Wigner formalism described in prior work~\cite{Relax} is a helpful analytic framework to check computational work for potential numerical artifacts.

   hep-phastro-ph.COPRD(2022)·33 citations
10. 10*

    Neutrinos: from the r-process to the diffuse supernova neutrino background

    Volpe Maria Cristina🇫🇷

    Neutrinos from dense environments are connected to the longstanding open questions of how massive stars explode and what are the sites where $r$-process elements are made. Flavor evolution and neutrino properties can influence nucleosynthetic abundances. GW170817 has given indirect evidence for r-process elements in binary neutron star mergers. We discuss the impact of non-standard interactions in such sites. Nearby compact objects, strong gravitational fields are present. We discuss their influence upon neutrino decoherence in a wave packet treatment of neutrino propagation. We conclude by mentioning the upcoming measurement of the diffuse supernova neutrino background.

    hep-phastro-ph.HEJ.Phys.Conf.Ser.(2021)·0 citations
11. 11*

    Higher mass spectra of the fully-charmed and fully-bottom tetraquarks

    Feng-Xiao Liu🇨🇳 · Ming-Sheng Liu🇨🇳 · Xian-Hui Zhong🇨🇳 · Qiang Zhao🇨🇳

    In this work, we calculate the higher mass spectra for the $2S$- and $1D$-wave fully-charmed and fully-bottom tetraquark states in a nonrelativistic potential quark model. The $2S$-wave fully-charmed/bottom tetraquark states lie in the mass range of $\sim (6.9,7.1)$/$(19.7,19.9)$ GeV, apart for the highest $0^{++}$ state $T_{(cc\bar{c}\bar{c})0^{++}}(7185)$/ $T_{(bb\bar{b}\bar{b})0^{++}}(19976)$. Most of the $2S$-wave states highly overlap with the high-lying $1P$-wave states. The masses for the $1D$-wave fully-charmed/bottom tetraquarks are predicted to be in the range of $\sim (6.7,7.2)/(19.5,20.0)$ GeV. The mass range for the $D$-wave tetraquark states cover most of the mass range of the $P$-wave states and the whole mass range of the $2S$-wave states. The narrow structure $X(6900)$ recently observed at LHCb in the di-$J/\psi$ invariant mass spectrum may be caused by the $1P$-, or $2S$-, or $1D$-wave $T_{cc\bar{c}\bar{c}}$ states. The vague structure $X(7200)$ may be caused by the highest $2S$-wave state $T_{(cc\bar{c}\bar{c})0^{++}}(7185)$, two low-lying $3S$-wave states $T_{(cc\bar{c}\bar{c})0^{++}}(7240)$ and $T_{(cc\bar{c}\bar{c})2^{++}}(7248)$, and/or the high-lying $1D$-wave states with masses around 7.2 GeV and $J^{PC}=0^{++},1^{++},2^{++},3^{++}$, or $4^{++}$. While it is apparent that the potential quark model calculations predict more states than the structures observed in the di-$J/\psi$ invariant mass spectrum, our calculations will help further understanding of the properties of these fully-heavy tetraquark states in their strong and magnetic interactions with open channels based on explicit quark model wave functions.

    hep-phhep-exPRD(2021)·65 citations
12. 12*

    Supernova Constraints on Dark Flavored Sectors

    Jorge Terol-Calvo🇪🇸

    Proto-neutron stars forming a few seconds after core-collapse supernovae are hot and dense environments where hyperons can be efficiently produced by weak processes. By making use of various state-of-the-art supernova simulations combined with the proper extensions of the equations of state including $\Lambda$ hyperons, we calculate the cooling of the star induced by the emission of dark particles $X^0$ through the decay $\Lambda \to n{X}^0$. Comparing this novel energy-loss process to the neutrino cooling of SN 1987A allows us to set a stringent upper limit on the branching fraction, BR$(\Lambda \to n{X}^0)\le 8\times 10^{-9}$, that we apply to massless dark photons and axions with flavor-violating couplings to quarks. We find that the new supernova bound can be orders of magnitude stronger than other limits in dark-sector models.

    hep-phastro-ph.HEJ.Phys.Conf.Ser.(2021)·0 citations
13. 13*

    Effective comparison of neutrino-mass models

    Rupert Coy🇧🇪 · Michele Frigerio🇫🇷

    New physics in the lepton sector may account for neutrino masses, affect electroweak precision observables, induce charged-lepton flavour violation, and shift dipole moments. The low-energy predictions of different models are most conveniently compared within the formalism of effective field theory. To illustrate the benefits of this approach, we derive the Wilson coefficients for a set of representative models: the fermionic seesaw mechanisms (type I and III), the Zee model, and a minimal leptoquark model. In each case, the Weinberg and the dipole operators have qualitatively different origins. In parallel, we present the model-independent constraints on the Wilson coefficients coming from various lepton observables. We then show that it becomes straightforward to understand the allowed parameter space for each model, and to discriminate between them. The Zee and leptoquark models are suitable to address the muon $g-2$ anomaly. We also confront the models with the anomalies in the W-boson mass and semileptonic $B$-meson decays.

    hep-phPRD(2022)·24 citations
14. 14*

    Long-range neutrinoless double beta decay mechanisms

    Jenni Kotila🇫🇮 · Jacopo Ferretti🇫🇮 · Francesco Iachello🇺🇸

    Understanding the origin of lepton number violation is one of the fundamental questions in particle physics today. Neutrinoless double beta decay provides a way in which this violation can be tested. In this article, we derive the form of hadronic and leptonic matrix elements for all possible long-range mechanisms of neutrinoless double beta decay. With these, we calculate the numerical values of the nuclear matrix elements (NME) and phase space factors (PSF) by making use of the interacting boson model of the nucleus (IBM-2) for NMEs and of exact Dirac wave functions for the PSFs. We show that:\ (I) lepton number violation can occur even with zero (or very small) neutrino mass and (II) the angular correlations of the emitted electrons can distinguish between different models of non-standard (NS) mechanisms. We set limits on the coupling constants of some NS models, in particular Left-Right models and SUSY models.

    hep-phnucl-th16 citations
15. 15*

    Higher spin glueballs from functional methods

    Markus Q. Huber🇩🇪 · Christian S. Fischer🇩🇪 · Helios Sanchis-Alepuz🇦🇹

    We calculate the glueball spectrum for spin up to J=4 and positive charge parity in pure Yang-Mills theory. We construct the full bases for J=0,1,2,3,4 and discuss the relation to gauge invariant operators. Using a fully self-contained truncation of Dyson-Schwinger equations as input, we obtain ground states and first and second excited states from extrapolations of the eigenvalue curves. Where available, we find good quantitative agreement with lattice results.

    hep-phEPJC(2021)·53 citations
16. 16*

    Phenomenological Effects of CPT and Lorentz Invariance Violation in Particle and Astroparticle Physics

    Vito Antonelli🇮🇹 · Lino Miramonti🇮🇹 · Marco Danilo Claudio Torri🇮🇹

    It is well known that a fundamental theorem of Quantum Field Theory (QFT) set in at spacetime ensures the CPT invariance of the theory. This symmetry is strictly connected to the Lorentz covariance, and consequently to the fundamental structure of spacetime. Therefore it may be interesting to investigate the possibility of departure from this fundamental symmetry, since it can furnish a window to observe possible effects of a more fundamental quantum gravity theory in a "lower energy limit". Moreover, in the past, the inquiry of symmetry violations provided a starting point for new physics discoveries. A useful physical framework for this kind of search is provided by astroparticle physics, thanks to the high energy involved and to the long path travelled by particles accelerated by an astrophysical object and then revealed on Earth. Astrophysical messengers are therefore very important probes for investigating this sector, involving high energy photons, charged particles, and neutrinos of cosmic origin. In addition, one can also study artificial neutrino beams, investigated at accelerator experiments. Here we discuss the state of art for all these topics and some interesting new proposals, both from a theoretical and phenomenological point of view.

    hep-phSymmetry(2020)·18 citations
17. 17*

    Neutrino Oscillations and Lorentz Invariance Violation

    Marco Danilo Claudio Torri🇮🇹

    This work explores the possibility of resorting to neutrino phenomenology to detect evidence of new physics, caused by the residual signals of the supposed quantum structure of spacetime. In particular, this work investigates the effects on neutrino oscillations and mass hierarchy detection, predicted by models that violate Lorentz invariance, preserving the spacetime isotropy and homogeneity. Neutrino physics is the ideal environment where conducting the search for new "exotic" physics, since the oscillation phenomenon is not included in the original formulation of the minimal Standard Model (SM) of particles. The confirmed observation of the neutrino oscillation phenomenon is, therefore, the first example of physics beyond the SM and can indicate the necessity to resort to new theoretical models. In this work, the hypothesis that the supposed Lorentz Invariance Violation (LIV) perturbations can influence the oscillation pattern is investigated. LIV theories are indeed constructed assuming modified kinematics, caused by the interaction of massive particles with the spacetime background. This means that the dispersion relations are modified, so it appears natural to search for effects caused by LIV in physical phenomena governed by masses, as in the case of neutrino oscillations. In addition, the neutrino oscillation phenomenon is interesting since there are three different mass eigenstates and in a LIV scenario, which preserves isotropy, at least two different species of particle must interact.

    hep-phhep-thUniverse(2020)·25 citations
18. 18*

    Strangelets at finite temperature in an equivparticle model

    H. M. Chen🇨🇳 · C. J. Xia🇨🇳 · G. X. Peng🇨🇳

    The properties of strangelets at finite temperature are studied within the framework of an equivparticle model, where a new quark mass scaling and self-consistent thermodynamic treatment are adopted. The effects of finite volume and Coulomb energy are taken into account. Our results show that the temperature T, baryon number A and perturbation interactions have strong influences on the properties of strangelets. It is found that the energy per baryon M/A and charge-to-mass ratio fz decrease with baryon number A, while the mechanically stable radius R and strangeness per baryon fs are increasing. For a strangelet with a fixed baryon number, we note that as temperature T increases the quantites M/A, R, and fs are increasing while fz is decreasing. The effects of confinement and perturbative interactions are investigated as well by readjusting the corresponding parameters.

    hep-phnucl-thPRD(2022)·16 citations
19. 19*

    Tagging the initial state gluon in the Z+jet process

    Simone Caletti🇮🇹

    We develop a jet flavour tagger in the contest of electroweak boson production in association with jets. Here the jet with the highest transverse momentum is considered and a simple cut on a jet angularity may serve as a tagger for the flavour of the jet. This is an infrared and collinear (IRC) safe procedure thus it is well-defined from a theoretical viewpoint. Jet angularities exibit a property called Casimir Scaling (CS) at the leading logarithmic (LL) accuracy. Here we consider also the first deviation from the typical CS behaviour because we use the most recent jet angularities calculations. Tagging the leading jet as quark-initiated permits us to enhance the initial-state gluon purity. We will consider transverse momentum distributions for tagged and no-tagged jets, with and without grooming. They could be potentially interesting observables to probe gluonic degrees of freedom of the colliding protons. In particular it may be worth to investigate if such a study might be a new handle on the determination of the gluon parton distribution function (PDF).

    hep-phPoS(2021)·0 citations
20. 20*

    Higgs-plus-jet inclusive production as stabilizer of the high-energy resummation

    Francesco Giovanni Celiberto🇮🇹 · Michael Fucilla🇮🇹 · Dmitry Yu. Ivanov🇷🇺 · Mohammed M.A. Mohammed🇮🇹 · Alessandro Papa🇮🇹

    We investigate the inclusive hadroproduction of a Higgs boson in association with a jet, featuring large transverse momenta and separated by a large rapidity distance. We propose this reaction, that can be studied at the LHC as well as at new-generation colliding machines, as a novel probe channel for the manifestation of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics. We bring evidence that high-energy resummed distributions in rapidity and transverse momentum exhibit a solid stability under higher-order corrections, thus offering us a faultless chance to gauge the feasibility of precision calculations of these observables at high energies. We come out with the message that future, exhaustive analyses of the inclusive Higgs-boson production, would benefit from the inclusion of high-energy effects in a multi-lateral formalism where distinct resummations are concurrently embodied. We propose these studies with the aim of inspiring synergies with other Communities, and pursuing the goal of widening common horizons in the exploration of the Higgs-physics sector.

    hep-phPoS(2022)·26 citations
21. 21*

    Search for dark Higgs inflaton with curvature couplings at LHC experiments

    Lucia Aurelia Popa (Institute of Space Science Bucharest-Magurele, Ro-077125 Romania)🇷🇴

    We analyse the dark Higgs inflation model with curvature corrections and explore the possibility to test its predictions by the particle physics experiments at LHC. We show that the dark Higgs inflation model with curvature corrections is strongly favoured by the present cosmological observations. The cosmological predictions of this model, including the quantum corrections of dark Higgs coupling constants and the uncertainty in estimation of the reheating temperature, lead to the dark Higgs mass $m_{\varphi }=0.919\pm$ 0.211 GeV and the mixing angle $\theta =1.492\pm$ 0.045 (at 68\% CL). We evaluate the FASER and MAPP-1 experiments reach for dark Higgs inflaton mass and mixing angle in the 95\% CL cosmological confidence region for an integrated luminosity of 3ab${}^{-1}$ at 13 TeV LHC, assuming 100\% detection efficiency. We conclude that the dark Higgs inflation model with curvature corrections is a compelling inflation scenario based on particle physics theory favoured by the present cosmological measurements that leaves imprints in the dark Higgs boson searchers at LHC.

    hep-phastro-ph.COUniverse(2022)·9 citations
22. 22*

    Evidence supporting the existence of $P_c(4380{)}^{\pm }$ from the recent measurements of $B_s\to J/\psi p\bar{p}$

    Jun-Zhang Wang🇨🇳 · Xiang Liu🇨🇳 · Takayuki Matsuki🇯🇵

    Very recently, the LHCb collaboration released the newest measurements of $B_s\to J/\psi p\bar{p}$, where an enhancement structure near 4.34 GeV was observed in the invariant mass spectrum of $J/\psi p$ with the statistical significance of $3.1-3.7$ $\sigma$. In this work, by performing a combined analysis for the three invariant mass spectra of $B_s\to J/\psi p\bar{p}$, we find that this $J/\psi p$ structure near 4.34 GeV can correspond to the contributions from the $P_c(4380{)}^{+}$ state with the assumption of $J^P=3/2^{-}$ together with the reflections of $B_s\to (f_2^{\ast }\to p\bar{p})J/\psi$. Here, $P_c(4380)$ was first observed in ${\Lambda }_b\to J/\psi pK$ but not confirmed in the updated LHCb data in 2019, and $f_2^{\ast }$ means the exciting light isoscalar tensor meson around 2.0 GeV. Thus, this provides a possible evidence to support the existence of the pentaquark $P_c(4380)$. Specifically, the assumed spin parity $J^P=3/2^{-}$ of $P_c(4380)$ is consistent with a prediction of the theoretical explanation of an $S$-wave $\bar{D}{\Sigma }_c^{\ast }$ molecular bound state.

    hep-phPRD(2021)·14 citations
23. 23*

    PYTHIA 8 underlying event tune For RHIC energies

    Manny Rosales Aguilar🇺🇸 · Zilong Chang🇺🇸 · Raghav Kunnawalkam Elayavalli🇺🇸 · Renee Fatemi🇺🇸 · Yang He🇨🇳 · Yuanjing Ji🇺🇸 · Dmitry Kalinkin🇺🇸 · Matthew Kelsey🇺🇸 · Isaac Mooney🇺🇸 · Veronica Verkest🇺🇸

    We report an underlying event tune for the PYTHIA 8 Monte Carlo event generator that is applicable for hadron collisions primarily at $\sqrt{s}$ ranges available at the Relativistic Heavy-Ion Collider (RHIC). We compare our new PYTHIA 8 tuned predictions to mid-rapidity inclusive ${\pi }^{\pm }$ spectra, jet sub-structure, Drell-Yan production, and underlying event measurements from RHIC and the Tevatron, as well as underlying event data from the Large Hadron Collider. With respect to the default PYTHIA 8 Monash Tune, the new `Detroit' tune shows significant improvements in the description of the experimental data. Additionally, we explore the validity of PYTHIA 8 predictions for forward rapidity $\pi$ in $\sqrt{s}$ = 200 GeV collisions, where neither tune is able to sufficiently describe the data. We advocate for the new tune to be used for PYTHIA 8 studies at current and future RHIC experiments, and discuss future tuning exercises at lower center-of-mass energies, where forward/backward kinematics are essential at the upcoming Electron-Ion collider.

    hep-phPRD(2022)·39 citations
24. 24*

    Accessing the pion 3D structure at US and China Electron-Ion Colliders

    J. M. Morgado Chávez🇪🇸 · V. Bertone🇫🇷 · F. De Soto🇪🇸 · M. Defurne🇫🇷 · C. Mezrag🇫🇷 · H. Moutarde🇫🇷 · J. Rodríguez-Quintero🇪🇸 · J. Segovia🇪🇸

    We present in this letter the first systematic feasibility study of accessing generalised parton distributions of the pion at an electron-ion collider through deeply virtual Compton scattering at next-to-leading order. It relies on a state-of-the-art model, able to fulfil by construction all the theoretical constraints imposed on generalised parton distributions. Strikingly, our analysis shows that quarks and gluons interfere destructively and that gluon dominance could be spotted by a sign change of the DVCS beam spin asymmetry.

    hep-phnucl-thPRL(2022)·55 citations
25. 25*

    MSSM WIMPs-nucleon cross section for E${}_{\chi }<$ 500 GeV

    K. Fushimi🇯🇵 · M. E. Mosquera🇦🇷 · O. Civitarese🇦🇷

    Among dark-matter candidates are the WIMPs (Weekly Interacting Massive Particles). Low-threshold detectors could directly detect dark-matter by measuring the energy deposited by the particles. In this work we examine the cross section for the elastic scattering of WIMPs on nucleons, in the spin-dependent and spin-independent channels. WIMPs are taken as neutralinos in the context of the minimal super-symmetric extension of the standard model (MSSM). The dependence of the results with the adopted MSSM parameters is discussed.

    hep-phastro-ph.HEIJMPE(2020)·2 citations
26. 26*

    Flavor Symmetries in an SU(5) Model of Grand Unification

    Malte Lindestam🇸🇪 · Tommy Ohlsson🇸🇪 · Marcus Pernow🇸🇪

    We investigate the options for imposing flavor symmetries on a minimal renormalizable non-supersymmetric $\mathrm{SU}(5)$ grand unified theory, without introducing additional flavor-related fields. Such symmetries reduce the number of free parameters in the model and therefore lead to more predictive models. We consider the Yukawa sector of the Lagrangian, and search for all possible flavor symmetries. As a result, we find 25 distinct realistic flavor symmetry cases, with ${\mathbb{Z}}_2$, ${\mathbb{Z}}_3$, ${\mathbb{Z}}_4$, and $\mathrm{U}(1)$ symmetries, and no non-Abelian cases.

    hep-phJHEP(2022)·6 citations
27. 27*

    Prospects of fast flavor neutrino conversion in rotating core-collapse supernovae

    Akira Harada🇯🇵 · Hiroki Nagakura🇯🇵

    There is mounting evidence that neutrinos undergo fast flavor conversion (FFC) in core-collapse supernova (CCSN). In this letter, we investigate the roles of stellar rotation on the occurrence of FFC by carrying out axisymmetric CCSN simulations with full Boltzmann neutrino transport. Our result suggests that electron neutrino lepton number (ELN) angular crossings, which are the necessary and sufficient condition to trigger FFC, preferably occur in the equatorial region for rotating CCSNe. By scrutinizing the neutrino--matter interaction and neutrino radiation field, we find some pieces of evidence that the stellar rotation facilitates the occurrence of FFC. The low-electron-fraction region in the post-shock layer expands by centrifugal force, enhancing the disparity of neutrino absorption between electron-type neutrinos (${\nu }_{\mathrm{e}}$) and their anti-particles (${\bar{\nu }}_{\mathrm{e}}$). This has a significant impact on the angular distribution of neutrinos in momentum space, in which ${\nu }_{\mathrm{e}}$ tends to be more isotropic than ${\bar{\nu }}_{\mathrm{e}}$; consequently, ELN crossings emerge. The ELN crossing found in this study is clearly associated with rotation, which motivates further investigation on how the subsequent FFC influences explosion dynamics, nucleosynthesis, and neutrino signals in rotating CCSNe.

    ↳ astro-ph.HEhep-phApJ(2022)·62 citations
28. 28*

    Modification of transition radiation by three-dimensional topological insulators

    O. J. Franca🇩🇪 · Stefan Yoshi Buhmann🇩🇪

    We study how transition radiation is modified by the presence of a generic magnetoelectric medium with a special focus on topological insulators. To this end, we use the Green's function for the electromagnetic field in presence of a plane interface between two topological insulators with different topological parameters, permittivities and permeabilities. We employ the far-field approximation together with the steepest descent method to obtain approximate analytical expressions for the electromagnetic field. Through this method we find that the electric field is a superposition of spherical waves and lateral waves. Contributions of both kind can be attributed to a purely topological origin. After computing the angular distribution of the radiation, we find that in a region far from the interface the main contribution to the radiation comes from the spherical waves. We present typical radiation patterns for the topological insulator TlBiSe${}_2$ and the magnetoelectric TbPO${}_4$. In the ultra-relativistic case, the additional contributions from the magnetoelectric coupling appreciably enhance the global maximum of the angular distribution. We also present an analytic expression for the frequency distribution of the radiation for this case. We find that in the limit where the permittivities are equal there still exists transition radiation of the order of the square of the topological parameter with a pure topological origin.

    ↳ cond-mat.mes-hallhep-phhep-thPRB(2022)·14 citations
29. 29*

    The $S_8$ Tension in Light of Updated Redshift-Space Distortion Data and PAge Approximation

    Lu Huang🇨🇳 · Zhiqi Huang🇨🇳 · Huan Zhou🇨🇳 · Zhuoyang Li🇨🇳

    One of the most prominent challenges to the standard Lambda cold dark matter ($\Lambda$CDM) cosmology is the tension between the structure growth parameter $S_8$ constrained by the cosmic microwave background (CMB) data and the smaller one suggested by the cosmic shear data. Recent studies show that, for $\Lambda$CDM cosmology, redshift-space distortion (RSD) data also prefers a smaller $S_8$ that is $\sim 2$-$3\sigma$ lower than the CMB value, but the result is sensitive to the cosmological model. In the present work we update the RSD constraint on $S_8$ with the most up-to-date RSD data set where the correlation between data points are properly taken into account. To reduce the model dependence, we add in our Monte Carlo Markov Chain calculation the most up-to-date data sets of Type Ia supernovae (SN) and baryon acoustic oscillations (BAO), whose correlation with RSD is also taken into account, to constrain the background geometry. For $\Lambda$CDM cosmology we find $S_8=0.812\pm 0.026$, which is $\sim 2\sigma$ larger than previous studies, and hence is consistent with the CMB constraint. By replacing $\Lambda$CDM with the Parameterization based on cosmic Age (PAge), an almost model-independent description of the late universe, we find that the RSD + SN + BAO constraint on $S_8$ is insensitive to the cosmological model.

    ↳ astro-ph.COgr-qchep-phhep-thSCPMA(2022)·21 citations
30. 30*

    Insight from the elliptic flow of identified hadrons measured in relativistic heavy-ion collisions

    Prabhupada Dixit🇮🇳 · Md. Nasim🇮🇳

    In this paper, we have discussed the transverse momentum dependence of elliptic flow measured in relativistic heavy-ion collisions. The transverse momentum dependence of the number of constituent quarks ($n_q$) scaled $v_2$ is obtained for all the measured identified hadrons. The $n_q$ scaled $\varphi$ $v_2$ is found to be similar to $n_q$ scaled $\Omega$ $v_2$. This indicates that both $\varphi$ and $\Omega$ are produced through quark recombination at RHIC energies. We also find $n_q$ scaled proton $v_2$ ($v_2$ of light quarks) is higher than $n_q$ scaled $\varphi$ and $\Omega$ $v_2$ ($v_2$ of strange quarks) at $p_T/n_q$ $<$ 1.0 GeV/c. This can be explained by considering quark $v_2$ is proportional to its transverse kinetic energy considering mass of deconfined light and strange quarks equal to $\sim$4 MeV and $\sim$ 140 MeV, respectively.

    ↳ nucl-exhep-exhep-phnucl-thIJMPE(2022)·0 citations
31. 31*

    Higgs scalar potential coupled to gravity in the exponential parametrization in arbitrary gauge

    Nobuyoshi Ohta🇹🇼 · Masatoshi Yamada🇩🇪

    We study the parametrization and gauge dependences in the Higgs field coupled to gravity in the context of asymptotic safety. We use the exponential parametrization to derive the fixed points for the cosmological constant, Planck mass, Higgs mass and its coupling, keeping arbitrary gauge parameters $\alpha$ and $\beta$, and compare the results with the linear split. We find that the beta functions for the Higgs potential are expressed in terms of redefined Planck mass such that the apparent gauge dependence is absent. Only the trace mode of the gravity fluctuations couples to the Higgs potential and it tends to decouple in the large $\beta$ limit, but the anomalous dimension becomes large, invalidating the local potential approximation. This gives the limitation of the exponential parametrization. There are also singularities for some values of the gauge parameters but well away from these, we find rather stable fixed points and critical exponents. We thus find that there are regions for the gauge parameters to give stable fixed points and critical exponents against the change of gauge parameters. The Higgs coupling is confirmed to be irrelevant for the reasonable choice of gauge parameters.

    ↳ hep-thgr-qchep-phPRD(2022)·19 citations
32. 32*

    Protonium annihilation densities in a unitary coupled channel model

    Emanuel Ydrefors🇧🇷 · Jaume Carbonell🇫🇷

    We consider a unitary coupled channel model to describe the low energy proton-antiproton scattering and the lower Coulomb-like protonium states. The existence of deeper quasi-bound states of nuclear nature is found to be a consequence of the experimental data. The properties of these states as well as the protonium annihilation densities are described and the difference with respect to the optical models description are manifested.

    ↳ nucl-thhep-phnucl-exEPJA(2021)·4 citations
33. 33*

    Strange quark matter and proto-strange stars in an equivaparticle model

    H. M. Chen🇨🇳 · C. J. Xia🇨🇳 · G. X. Peng🇨🇳

    The properties of strange quark matter and the structures of (proto-)strange stars are studied within the framework of an equivparticle model, where a new quark mass scaling and self-consistent thermodynamic treatment are adopted. Our results show that the perturbative interaction has a strong impact on the properties of strange quark matter. It is found that the energy per baryon increases with temperature, while the free energy decreases and eventually becomes negative. At fixed temperatures, the pressure at the minimum free energy per baryon is zero, suggesting that the thermodynamic self-consistency is preserved. Additionally, the sound velocity v in quark matter approaches to the extreme relativistic limit (c/sqrt(3)) as the density increases. By increasing the strengths of confinement parameter D and perturbation parameter C, the tendency for v to approach the extreme relativistic limit at high density is slightly weakened. For (proto-)strange stars, in contrast to the quark mass scalings adopted in previous publications, the new quark mass scaling can accommodate massive proto-strange stars with their maximum mass surpassing twice the solar mass at T = 50 MeV.

    ↳ nucl-thhep-phCPC(2022)·8 citations
34. 34*

    Freezeout properties of different light nuclei at the RHIC Beam Energy Scan

    M. Waqas🇨🇳 · G. X. Peng🇨🇳 · Rui-Qin Wang🇨🇳 · Muhammad Ajaz🇵🇰 · Abd Al Karim Haj Ismail🇦🇪

    We study the transverse momentum spectra of light nuclei (deuteron, anti-deuteron and triton) produced in Gold-Gold (Au-Au) collisions in different centrality bins by the blast wave model with Tsallis statistics. The model results are in agreement with the experimental data measured by STAR Collaboration in special transverse momentum ranges. We extracted the kinetic freezeout temperature, transverse flow velocity and kinetic freezeout volume. It is observed that kinetic freezeout temperature and transverse flow velocity increases initially, and then saturates from 14.5-39 GeV, while the kinetic freezeout volume increase initially up to 19.6 GeV but saturates from 19.6-39 GeV. This may indicate that the phase transition starts in part volume that ends in the whole volume at 39 GeV and the critical point may exists somewhere in the energy range of 14.5-39 GeV. The present work observed that the kinetic freezeout temperature, transverse flow velocity and kinetic freezeout volume has a decreasing trend from central to peripheral collisions. We found the freezeout volume of triton is smaller than those of deuteron and anti-deuteron, which shows that triton freezeout earlier than that of deuteron and anti-deuteron.

    ↳ nucl-thhep-phEur.Phys.J.Plus(2021)·19 citations
35. 35*

    Establishing the Non-Primordial Origin of Black Hole-Neutron Star Mergers

    Misao Sasaki🇯🇵 · Volodymyr Takhistov🇯🇵 · Valeri Vardanyan🇯🇵 · Ying-li Zhang🇨🇳

    Primordial black holes (PBHs) from the early Universe constitute an attractive dark matter candidate. First detections of black hole-neutron star (BH-NS) candidate gravitational wave events by the LIGO/Virgo collaboration, GW200105 and GW200115, already prompted speculations about non-astrophysical origin. We analyze, for the first time, the total volumetric merger rates of PBH-NS binaries formed via two-body gravitational scattering, finding them to be subdominant to the astrophysical BH-NS rates. In contrast to binary black holes, a significant fraction of which can be of primordial origin, either formed in dark matter halos or in the early Universe, PBH-NS rates cannot be significantly enhanced by contributions preceding star formation. Our findings imply that the identified BH-NS events are of astrophysical origin, even when PBH-PBH events significantly contribute to the GW observations.

    ↳ astro-ph.COastro-ph.HEhep-phApJ(2022)·28 citations
36. 36*

    Dark Matter from Entropy Perturbations in Curved Field Space

    Hassan Firouzjahi🇮🇷 · Mohammad Ali Gorji🇯🇵 · Shinji Mukohyama🇯🇵 · Alireza Talebian🇮🇷

    The accumulated energy density of the excited entropy modes in multiple field inflationary scenarios can play the role of dark matter. In the usual case of a flat field space without any turning trajectory, only light superhorizon entropy modes can be excited through the gravitational instability. In the case of a negatively curved field space, we show that subhorizon entropy modes can be excited as well through the tachyonic instability induced by the negative curvature of the field space. The latter allows for production of entropy modes with masses larger than or at the order of the Hubble expansion rate during inflation, leading to a new dark matter scenario. Due to the contribution of subhorizon modes, the corresponding spectral density has a peak at a scale smaller than its counterpart in the models based on a flat field space. This difference makes our model observationally distinguishable.

    ↳ gr-qcastro-ph.COhep-phhep-thPRD(2022)·14 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.