Thu·May 27, 2021Thursday·May 27, 2021

1. 01*

   Quarkonium dissociation properties of hot QCD medium at momentum-anisotropy in the N-dimensional space using Quasi-particle Debye mass with finite baryonic chemical potential

   Vineet Kumar Agotiya🇮🇳 · Siddhartha Solanki🇮🇳 · Manohar Lal🇮🇳

   The analytical exact iteration method (AEIM) have been used to calculate the N-dimensional radial schrodinger equation with the real part of complex-valued potential and it is generalized to the finite value of anisotropy ({\xi}), temperature and baryonic chemical potential. In N-dimensional space the energy eigen values have been calculated for any states (n,l). The present results have been used to study the properties of quarkonium states (i.e, the binding energy and mass spectra in the N-dimensional space). The influences of anisotropy ({\xi}) on the dissociation temperature(TD) has been also calculated for the ground state of quarkonia at N=0 and \mu = 300MeV . The anisotropy in oblate case, thus obtained, makes the dissociation temperature(TD) lower as compared to the isotropic case . We also seen that Leading order Debye mass is greater than that of Quasi-particle Debye mass after introducing the baryonic chemical potential.

   hep-ph3 citations
2. 02*

   Unleashing the full power of LHCb to probe Stealth New Physics

   Martino Borsato · Xabier Cid Vidal · Yuhsin Tsai · Carlos Vázquez Sierra · José Zurita · Gonzalo Alonso-Álvarez · Alexey Boyarsky · Alexandre Brea Rodríguez · Diogo Buarque Franzosi · Giacomo Cacciapaglia · Adrián Casais Vidal · Mingxuan Du and 29 other authors

   In this paper, we describe the potential of the LHCb experiment to detect Stealth physics. This refers to dynamics beyond the Standard Model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.

   hep-phhep-exhep-thRept.Prog.Phys.(2022)·53 citations
3. 03*

   One-loop constituent quark contributions to the vector and axial-vector meson curvature mass

   Győző Kovács🇭🇺 · Péter Kovács🇭🇺 · Zsolt Szép🇭🇺

   The renormalized contribution of fermions to the curvature masses of vector and axial-vector mesons is derived with two different methods at leading order in the loop expansion applied to the (2+1)-flavor constituent quark-meson model. The corresponding contribution to the curvature masses of the scalar and pseudoscalar mesons, already known in the literature, is rederived in a transparent way. The temperature dependence of the curvature mass of various (axial-)vector modes obtained by decomposing the curvature mass tensor is investigated along with the (axial-)vector--(pseudo)scalar mixing. All fermionic corrections are expressed as simple integrals that involve at finite temperature only the Fermi-Dirac distribution function modified by the Polyakov-loop degrees of freedom. The renormalization of the (axial-)vector curvature mass allows us to lift a redundancy in the original Lagrangian of the globally symmetric extended linear sigma model, in which terms already generated by the covariant derivative were reincluded with different coupling constants.

   hep-phPRD(2021)·17 citations
4. 04*

   Constraining nuclear effects in Argon using machine learning algorithms

   Srishti Nagu🇮🇳 · Jaydip Singh🇮🇳 · Jyotsna Singh🇮🇳 · R.B. Singh🇮🇳

   Neutrino oscillation experiments aim to measure the neutrino oscillation parameters with accuracy and achieve a complete understanding of neutrino physics. For determining the neutrino oscillation parameters, knowledge of neutrino energy is a prerequisite. But neutrino energy needs to be reconstructed, based on the particles in the final state that emerge out of the nucleus following a neutrino-nucleus interaction. Current and upcoming neutrino oscillation experiments use heavy nuclear targets (viz. Argon(Ar), Calcium(Ca), etc.) but the neutrino scattering with such targets becomes complicated as compared to that with a clean target like Hydrogen(H). This work explores the viability of using machine learning algorithms (MLA) in reconstructing neutrino energy. We use final state kinematics generated from two neutrino event generators viz. GENIE and GiBUU to train the MLA. We calculate the Ar/H ratio in an attempt to quantify nuclear effects in the Ar target. We observe a significant improvement in our results when we train the MLA by combining the FSI kinematics of neutrino interactions from both the neutrino event generators.

   hep-ph1 citation
5. 05*

   SN1987A still shining: A Quest for Pseudo-Dirac Neutrinos

   Ivan Martinez-Soler🇺🇸 · Yuber F. Perez-Gonzalez🇺🇸 · Manibrata Sen🇺🇸

   Ever since the discovery of neutrinos, we have wondered if neutrinos are their own antiparticles. One remarkable possibility is that neutrinos have a pseudo-Dirac nature, predicting a tiny mass difference between active and sterile states. We analyze the neutrino data from SN1987A in the light of active-sterile oscillations and find a mild preference ($\Delta {\chi }^2\approx 3$) for $\delta m^2=6.31\times 10^{-20}{\mathrm{eV}}^2$. Notably, the same data is able to exclude $\delta m^2\sim [2.55,3.01]\times 10^{-20}{\mathrm{eV}}^2$ with $\Delta {\chi }^2>9$, the tiniest mass differences constrained so far. We further consider the next-generation of experiments and demonstrate their sensitivity exploring the nature of the neutrino mass.

   hep-phastro-ph.HEPRD(2022)·32 citations
6. 06*

   Renormalization and non-renormalization of scalar EFTs at higher orders

   Weiguang Cao🇯🇵 · Franz Herzog🇬🇧 · Tom Melia🇯🇵 · Jasper Roosmale Nepveu🇩🇪

   We renormalize massless scalar effective field theories (EFTs) to higher loop orders and higher orders in the EFT expansion. To facilitate EFT calculations with the R* renormalization method, we construct suitable operator bases using Hilbert series and related ideas in commutative algebra and conformal representation theory, including their novel application to off-shell correlation functions. We obtain new results ranging from full one loop at mass dimension twelve to five loops at mass dimension six. We explore the structure of the anomalous dimension matrix with an emphasis on its zeros, and investigate the effects of conformal and orthonormal operators. For the real scalar, the zeros can be explained by a `non-renormalization' rule recently derived by Bern et al. For the complex scalar we find two new selection rules for mixing $n$- and $(n-2)$-field operators, with $n$ the maximal number of fields at a fixed mass dimension. The first appears only when the $(n-2)$-field operator is conformal primary, and is valid at one loop. The second appears in more generic bases, and is valid at three loops. Finally, we comment on how the Hilbert series we construct may be used to provide a systematic enumeration of a class of evanescent operators that appear at a particular mass dimension in the scalar EFT.

   hep-phhep-thJHEP(2021)·28 citations
7. 07*

   Multi-track Displaced Vertices at B-Factories

   Mason Acevedo🇺🇸 · Albany Blackburn🇺🇸 · Nikita Blinov🇺🇸 · Brian Shuve🇺🇸 · Mavis Stone🇺🇸

   We propose a program at B-factories of inclusive, multi-track displaced vertex searches, which are expected to be low background and give excellent sensitivity to non-minimal hidden sectors. Multi-particle hidden sectors often include long-lived particles (LLPs) which result from approximate symmetries, and we classify the possible decays of GeV-scale LLPs in an effective field theory framework. Considering several LLP production modes, including dark photons and dark Higgs bosons, we study the sensitivity of LLP searches with different number of displaced vertices per event and track requirements per displaced vertex, showing that inclusive searches can have sensitivity to a large range of hidden sector models that are otherwise unconstrained by current or planned searches.

   hep-phhep-exJHEP(2021)·11 citations
8. 08*

   $H_0$ tension without CMB data: beyond the $\Lambda$CDM

   Fumiya Okamatsu · Toyokazu Sekiguchi🇯🇵 · Tomo Takahashi🇯🇵

   We investigate the $H_0$ tension in a range of extended model frameworks beyond the standard $\Lambda$CDM without the data from cosmic microwave background (CMB). Specifically, we adopt the data from baryon acoustic oscillation, big bang nucleosynthesis and type Ia supernovae as indirect measurements of $H_0$ to study the tension. We show that the estimated value of $H_0$ from indirect measurements is overall lower than that from direct local ones regardless of the data sets and a range of extended models to be analyzed, which indicates that, although the significance of the tension varies depending on models, the $H_0$ tension persists in a broad framework beyond the standard $\Lambda$CDM model even without CMB data.

   ↳ astro-ph.COgr-qchep-phPRD(2021)·16 citations
9. 09*

   Analytical WKB theory for high-harmonic generation and its application to massive Dirac electrons

   Hidetoshi Taya🇯🇵 · Masaru Hongo🇺🇸 · Tatsuhiko N. Ikeda🇯🇵

   We propose an analytical approach to high-harmonic generation (HHG) for nonperturbative low-frequency and high-intensity fields based on the (Jeffreys-)Wentzel-Kramers-Brillouin (WKB) approximation. By properly taking into account Stokes phenomena of WKB solutions, we obtain wavefunctions that systematically include the repetitive dynamics of production and acceleration of electron-hole pairs and quantum interference due to phase accumulation between different pair production times (Stückelberg phase). Using the obtained wavefunctions without relying on any phenomenological assumptions, we explicitly compute electric current (including intra- and inter-band contributions) as the source of HHG for a massive Dirac system in (1+1)-dimensions under an ac electric field. We demonstrate that the WKB approximation agrees well with numerical results obtained by solving the time-dependent Schrödinger equation and point out that the quantum interference is important in HHG. We also predict in the deep nonperturbative regime that (1) harmonic intensities oscillate with respect to electric-field amplitude $E_0$ and frequency $\Omega$, with a period determined by the Stückelberg phase; (2) the cutoff order of HHG is determined by $2e{E}_0/\hslash {\Omega }^2$, with $e$ being the electron charge; and that (3) non-integer harmonics, controlled by the Stückelberg phase, appear as a transient effect. Our WKB theory is particularly suited for a parameter regime, where the Keldysh parameter $\gamma =(\Delta /2)\Omega /e{E}_0$, with $\Delta$ being the gap size, is small. This parameter regime corresponds to intense lasers in the terahertz regime for realistic massive Dirac materials. Our analysis implies that the so-called HHG plateau can be observed at the terahertz frequency within the current technology.

   ↳ cond-mat.str-elcond-mat.mes-hallhep-phphysics.optics+1PRB(2021)·13 citations
10. 10*

    From Cosmic Matter to the Laboratory

    Anton Motornenko🇩🇪 · Jan Steinheimer🇩🇪 · Horst Stoecker🇩🇪

    The recent discovery of binary neutron star mergers has opened a new and exciting venue of research into hot and dense strongly interacting matter. For the first time this elusive state of matter, described by the theory of quantum chromo dynamics, can be studied in two very different environments. On the macroscopic scale in the collisions of neutron stars and on the microscopic scale in collisions of heavy ions at particle collider facilities. We will discuss the conditions that are created in these mergers and the corresponding high energy nuclear collisions. This includes the properties of QCD matter, i.e. the expected equation of state as well as expected chemical and thermodynamic properties of this exotic matter. To explore this matter in the laboratory - a new research prospect is available at the Facility for Antiproton and Ion Research, FAIR. The new facility is being constructed adjacent to the existing accelerator complex of the GSI Helmholtz Center for Heavy Ion Research at Darmstadt/Germany, expanding the research goals and technical possibilities substantially. The worldwide unique accelerator and experimental facilities of FAIR will open the way for a broad spectrum of unprecedented research supplying a variety of experiments in hadron, nuclear, atomic and plasma physics as well as biomedical and material science which will be briefly described.

    ↳ nucl-thastro-ph.HEhep-phAstron.Nachr.(2021)·1 citation
11. 11*

    Isospin symmetry breaking in double-pion production in the region of $d^{\ast }(2380)$ and the scalar $\sigma$ meson

    M.N. Platonova🇷🇺 · V.I. Kukulin🇷🇺

    The first attempt is made to provide a quantitative theoretical interpretation of the WASA-at-COSY experimental data on the basic double-pion production reactions $pn\to d{\pi }^0{\pi }^0$ and $pn\to d{\pi }^{+}{\pi }^{-}$ in the energy region $T_p=1$ - $1.3$ GeV [P. Adlarson et al., Phys. Lett. B 721, 229 (2013)]. The data are analyzed within a model based on production and decay of an intermediate $I(J^P)=0(3^{+})$ dibaryon resonance ${\mathcal{D}}_{03}$ (denoted also as $d^{\ast }(2380)$). The observed decrease of the near-threshold enhancement (the so-called ABC effect) in the reaction $pn\to d{\pi }^{+}{\pi }^{-}$ in comparison to that in the reaction $pn\to d{\pi }^0{\pi }^0$ is explained (at least partially) to be due to isospin symmetry violation in the two-pion decay of an intermediate near-threshold scalar $\sigma$ meson emitted from the ${\mathcal{D}}_{03}$ dibaryon resonance under conditions of the partial chiral symmetry restoration.

    ↳ nucl-thhep-phPRD(2021)·4 citations
12. 12*

    Beating the Lyth bound by parametric resonance during inflation

    Yi-Fu Cai🇨🇳 · Jie Jiang🇨🇳 · Misao Sasaki🇯🇵 · Valeri Vardanyan🇯🇵 · Zihan Zhou🇨🇳

    We propose a novel mechanism for enhancing the primordial gravitational waves without significantly affecting the curvature perturbations produced during inflation. This is achieved due to non-linear sourcing of resonantly amplified scalar field fluctuations. Our result is an explicit scale-dependent counter-example of the famous Lyth bound, which opens up a promising perspective of producing detectable inflationary tensor modes with low-scale inflation and a sub-Planckian field excursion. We explicitly demonstrate the testability of our mechanism with upcoming Cosmic Microwave Background B-mode observations.

    ↳ astro-ph.COhep-phhep-thPRL(2021)·42 citations
13. 13*

    Harvesting quantum coherence from axion dark matter

    Sugumi Kanno🇯🇵 · Akira Matsumura🇯🇵 · Jiro Soda🇯🇵

    Quantum coherence is one of the most striking features of quantum mechanics rooted in the superposition principle. Recently it has been demonstrated that it is possible to harvest the quantum coherence from a coherent scalar field. In order to explore a new method of detecting axion dark matter, we consider a point-like Unruh-DeWitt detector coupled to the axion field and quantify a coherent measure of the detector. We show that the detector can harvest the quantum coherence from the axion dark matter. To be more precise, we consider a two-level of electron system in an atom as the detector. In this case, we obtain the coherence measure $C=2.2\times 10^{-6}\gamma \left(T/1\mathrm{s}\right)$ where $T$ and $\gamma$ are an observation time and the Lorentz factor. At the same time, the axion mass $m_a$ we can probe is determined by the energy gap of the detector.

    ↳ quant-phastro-ph.COhep-phMod.Phys.Lett.A(2022)·5 citations
14. 14*

    Do gamma-ray burst measurements provide a useful test of cosmological models?

    Narayan Khadka🇺🇸 · Orlando Luongo🇮🇹 · Marco Muccino🇰🇿 · Bharat Ratra🇺🇸

    We study eight different gamma-ray burst (GRB) data sets to examine whether current GRB measurements -- that probe a largely unexplored part of cosmological redshift ($z$) space -- can be used to reliably constrain cosmological model parameters. We use three Amati-correlation samples and five Combo-correlation samples to simultaneously derive correlation and cosmological model parameter constraints. The intrinsic dispersion of each GRB data set is taken as a goodness measurement. We examine the consistency between the cosmological bounds from GRBs with those determined from better-established cosmological probes, such as baryonic acoustic oscillation (BAO) and Hubble parameter $H(z)$ measurements. We use the Markov chain Monte Carlo method implemented in \textsc{MontePython} to find best-fit correlation and cosmological parameters, in six different cosmological models, for the eight GRB samples, alone or in conjunction with BAO and $H(z)$ data. For the Amati correlation case, we compile a data set of 118 bursts, the A118 sample, which is the largest -- about half of the total Amati-correlation GRBs -- current collection of GRBs suitable for constraining cosmological parameters. This updated GRB compilation has the smallest intrinsic dispersion of the three Amati-correlation GRB data sets we examined. We are unable to define a collection of reliable bursts for current Combo-correlation GRB data. Cosmological constraints determined from the A118 sample are consistent with -- but significantly weaker than -- those from BAO and $H(z)$ data. They also are consistent with the spatially-flat $\Lambda$CDM model as well as with dynamical dark energy models and non-spatially-flat models. Since GRBs probe a largely unexplored region of $z$, it is well worth acquiring more and better-quality burst data which will give a more definitive answer to the question of the title.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2021)·97 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.