Nuclear Theory·nucl-th

Friday·December 18, 2015

14 papers—8 primary·6 cross-listed

09
Weak and strong coupling equilibration in nonabelian gauge theories
Liam Keegan🇨🇭 · Aleksi Kurkela🇨🇭 · Paul Romatschke🇺🇸 · Wilke van der Schee🇺🇸 · Yan Zhu🇫🇮
We present a direct comparison studying equilibration through kinetic theory at weak coupling and through holography at strong coupling in the same set-up. The set-up starts with a homogeneous thermal state, which then smoothly transitions through an out-of-equilibrium phase to an expanding system undergoing boost-invariant flow. This first apples-to-apples comparison of equilibration provides a benchmark for similar equilibration processes in heavy-ion collisions, where the equilibration mechanism is still under debate. We find that results at weak and strong coupling can be smoothly connected by simple, empirical power-laws for the viscosity, equilibration time and entropy production of the system.
↳ hep-thhep-phnucl-thJHEP(2016)·105 citations
10
Measurements of correlations of anisotropic flow harmonics in Pb--Pb Collisions with ALICE
You Zhou (ALICE Collaboration)🇸🇪
We report the first measurements of the correlation strength between various anisotropic flow harmonics, using ALICE data. This correlation strength is characterized with multi-particle cumulants of mixed harmonics, which by construction depend only on the fluctuations of magnitudes of the anisotropic flow vectors. A detailed comparison to theoretical model calculations, including HIJING, Monte Carlo Glauber and hydrodynamics is also presented. These studies further constrain initial conditions, the properties and the evolution of the system to be used in theoretical simulations of heavy-ion collisions.
↳ nucl-exnucl-thNPA(2016)·11 citations
11
Electromagnetic Signatures of Neutron Star Mergers in the Advanced LIGO Era
Rodrigo Fernández🇺🇸 · Brian D. Metzger🇺🇸
The mergers of binaries containing neutron stars and stellar-mass black holes are the most promising sources for direct detection in gravitational waves by the interferometers Advanced LIGO and Virgo over the next few years. The concurrent detection of electromagnetic emission from these events would greatly enhance the scientific return of these discoveries. Here we review the state of the art in modeling the electromagnetic signal of neutron star binary mergers across different phases of the merger and multiple wavelengths. We focus on those observables which provide the most sensitive diagnostics of the merger physics and the contribution to the synthesis of rapid neutron capture ( $r$ -process) elements in the Galaxy. We also outline expected future developments on the observational and theoretical sides of this rapidly evolving field.
↳ astro-ph.HEastro-ph.SRgr-qcnucl-thAnn.Rev.Nucl.Part.Sci.(2016)·210 citations
12
Searching for charmoniumlike states with hidden $s s ˉ$
Xiao-Hai Liu🇯🇵 · Makoto Oka🇯🇵
We investigate the processes $e^{+} e^{-}$ $\to$ $γ J / ψ ϕ$ , $γ J / ψ ω$ and $π^{0} J / ψ η$ to search for the charmnium-like states with hidden $s s ˉ$ , such as $Y (4140)$ , $Y (4274)$ , $X (4350)$ and $X (3915)$ . These processes will receive contributions from the charmed-strange meson rescatterings. When the center-of-mass energies of the $e^{+} e^{-}$ scatterings are taken around the $D_{s 0} (2317) D_{s}^{*}$ , $D_{s 1} (2460) D_{s}$ or $D_{s 1} (2460) D_{s}^{*}$ threshold, the anomalous triangle singularities can be present in the rescattering amplitudes, which implies a non-resonance explanation about the resonance-like structures. The positions of the anomalous triangle singularities are sensitive to the kinematics, which offers us a criterion to distinguish the kinematic singularities from genuine particles.
↳ hep-phhep-exnucl-exnucl-thPRD(2016)·21 citations
13
Antiproton--proton annihilation into pion pairs within effective meson theory
Ying Wang🇫🇷 · Yury M. Bystritskiy🇷🇺 · Egle Tomasi-Gustafsson🇫🇷
Antiproton--proton annihilation into light mesons is revisited in the few GeV energy domain, in view of a global description of the existing data. An effective meson model is developed, with mesonic and baryonic degrees od freedom in $s$ , $t$ , and $u$ channels. Regge factors are added to reproduce the proper energy behavior and the forward and backward peaked behavior. A comparison with existing data and predictions for angular distributions and energy dependence are done for charged and neutral pion pair production.
↳ hep-phnucl-thPRC(2017)·5 citations
14
Axion electrodynamics and nonrelativistic photons in nuclear and quark matter
Naoki Yamamoto🇯🇵
We argue that the effective theory for electromagnetic fields in spatially varying meson condensations in dense nuclear and quark matter is given by the axion electrodynamics. We show that one of the helicity states of photons there has the nonrelativistic gapless dispersion relation $ω \sim k^{2}$ at small momentum, while the other is gapped. This "nonrelativistic photon" may also be realized at the interface between topological and trivial insulators in condensed matter systems.
↳ hep-thcond-mat.mes-hallnucl-thPRD(2016)·30 citations

Affiliations

first authorsco-authorsvia INSPIRE

Weak and strong coupling equilibration in nonabelian gauge theories

Measurements of correlations of anisotropic flow harmonics in Pb--Pb Collisions with ALICE

Electromagnetic Signatures of Neutron Star Mergers in the Advanced LIGO Era

Searching for charmoniumlike states with hidden ssˉ

Antiproton--proton annihilation into pion pairs within effective meson theory

Axion electrodynamics and nonrelativistic photons in nuclear and quark matter

Affiliations

Searching for charmoniumlike states with hidden $s s ˉ$