A5008152614- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Cosmology and Gravitation Theories
- Pulsars and Gravitational Waves Research
- Cold Atom Physics and Bose-Einstein Condensates
- Black Holes and Theoretical Physics
- Quantum, superfluid, helium dynamics
- Advanced Thermodynamics and Statistical Mechanics
- Gas Dynamics and Kinetic Theory
- Nuclear physics research studies
- Statistical Mechanics and Entropy
- Theoretical and Computational Physics
- Quantum Mechanics and Applications
- High-pressure geophysics and materials
- Spectroscopy and Quantum Chemical Studies
- Fluid Dynamics and Turbulent Flows
- Scientific Research and Discoveries
- Atomic and Subatomic Physics Research
- Superconducting Materials and Applications
- Gamma-ray bursts and supernovae
- Stochastic processes and statistical mechanics
- Particle Dynamics in Fluid Flows
- Quantum chaos and dynamical systems
- Atomic and Molecular Physics
Goethe University Frankfurt
2015-2024
Goethe Institute
2011-2024
Helmholtz Graduate School for Hadron and Ion Research
2024
GSI Helmholtz Centre for Heavy Ion Research
2023-2024
Duke University
1993-2021
Nile University
2020
Brookhaven National Laboratory
1993-2017
École Nationale Supérieure des Mines de Paris
2016
Laboratoire de Physique Subatomique et des Technologies Associées
2016
University of Houston
2016
We develop a new 3 + 1 dimensional Monte Carlo cascade solving the kinetic on-shell Boltzmann equations for partons including inelastic $gg\ensuremath{\leftrightarrow}ggg$ pQCD processes. The back reaction channel is treated---for first time---fully consistently within this scheme. An extended stochastic method used to solve collision integral. frame dependence and convergency are studied fixed tube with thermal initial conditions. detailed numerical analysis shows that fully covariant...
This writeup is a compilation of the predictions for forthcoming Heavy Ion Program at Large Hadron Collider, as presented CERN Theory Institute 'Heavy Collisions LHC - Last Call Predictions', held from May 14th to June 10th 2007.
We present a mechanism for the separation of strangeness from antistrangeness in deconfinement transition. For net zero total system, population s quarks is greatly enriched quark-gluon plasma, while s\ifmmode\bar\else\textasciimacron\fi{} drift into hadronic phase. This could result ``strangelet'' formation, i.e., metastable blobs strange-quark matter, which serve as unique signature plasma formation heavy-ion collisions.
A hadron resonance gas model including all known particles and resonances with masses m < 2 GeV an exponentially rising density of Hagedorn states for > is used to obtain upper bound on the shear viscosity entropy ratio, eta/s approximately 1/(4pi), hadronic matter near Tc. We found a large trace anomaly small speed sound Tc, which agree well recent lattice calculations. comment bulk ratio close
In an extended mean field theory, we find a large class of bound multistrange objects, formed from combinations {p,n,\ensuremath{\Lambda},${\mathrm{\ensuremath{\Xi}}}^{0}$,${\mathrm{\ensuremath{\Xi}}}^{\mathrm{\ensuremath{-}}}$} baryons, which are stable against strong decay. We predict maximal binding energy per baryon ${\mathit{E}}_{\mathit{B}}$/A\ensuremath{\approxeq}-21 MeV, strangeness ${\mathit{f}}_{\mathit{s}}$\ensuremath{\approxeq}1.2, charge...
The elliptic flow ${v}_{2}$ and the ratio of shear viscosity over entropy density, $\ensuremath{\eta}/s$, gluon matter are calculated from perturbative QCD (pQCD) based parton cascade Boltzmann approach multiparton scatterings. For $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s}=200A\text{ }\text{ }\mathrm{GeV}$ plasma generates large values measured BNL Relativistic Heavy Ion Collider. Standard pQCD yields $\ensuremath{\eta}/s\ensuremath{\approx}0.08--0.15$ as small lower bound found...
The space-time propagation of heavy quarks in ultrarelativistic ion collisions is studied within the partonic transport model Boltzmann approach multiparton scatterings (BAMPS). In this interact with medium via binary scatterings. cross sections for these interactions are calculated leading-order perturbative QCD, but feature a more precise Debye screening derived hard thermal loop approximation and obey running coupling. Within framework elliptic flow nuclear modification factor computed...
Electric conductivity is sensitive to effective cross sections among the particles of partonic medium. We investigate electric a hot plasma quarks and gluons, solving relativistic Boltzmann equation. In order extract this transport coefficient, we employ Green-Kubo formalism and, independently, method motivated by classical definition conductivity. To end evaluate static diffusion current upon influence an field. Both methods give identical results. For first time, obtain numerically Drude...
The electromagnetic response of hot QCD matter to decaying external magnetic fields is investigated. We examine the validity Ohm's law and find that induced electric current increases from zero relaxes towards value law. relaxation time larger than lifetime field for in relativistic heavy-ion collisions. lower-than-expected significantly suppresses makes incomplete. demonstrate incomplete by calculations employing parton transport model combined with solution Maxwell's equations. Our results...
We demonstrate that strangeness separates in the Gibbs-phase coexistence between a baryon-rich quark-gluon plasma and hadron matter, even at T=0. For finite temperatures this is due to associated production of kaons (containing s\ifmmode\bar\else\textasciimacron\fi{} quarks) phase while s quarks remain deconfined phase. The s-s\ifmmode\bar\else\textasciimacron\fi{} separation results strong enhancement s-quark abundance quark This mechanism further supported by cooling net enrichment...
We discuss the classical limit for long-distance (``soft'') modes of a quantum field when hard are in thermal equilibrium. address question correct semiclassical dynamics momentum cutoff $|\mathbf{p}|<~{k}_{c}\ensuremath{\ll}T$ is introduced. Higher order contributions lead to stochastic interpretation effective action analogy with Brownian motion, resulting dissipation and decoherence evolution soft modes. Particular emphasis put on understanding dissipation. Our discussion focuses mostly...
The quantum time evolution of \phi^4-field theory for a spatially homogeneous system in 2+1 space-time dimensions is investigated numerically out-of-equilibrium initial conditions on the basis Kadanoff-Baym equations including tadpole and sunset self-energies. Whereas self-energy yields dynamical mass, responsible dissipation an equilibration system. In particular we address dynamics spectral (`off-shell') distributions excited modes different phases approach to equilibrium described by...
Relativistic heavy ion collisions constitute a prolific source of hyperons: tens hyperons per event are predicted at energies E\ensuremath{\ge}10 GeV/nucleon, providing scenario for the formation metastable exotic multihypernuclear objects. They may exhibit exceptional properties: bound neutral (e.g., $^{4}$${\mathit{M}}_{2\mathrm{\ensuremath{\Lambda}}}^{2\mathit{n}}$, $^{10}$${\mathit{M}}_{2\mathrm{\ensuremath{\Lambda}}}^{8\mathit{n}}$, pure \ensuremath{\Lambda} droplets,...
The relation of the shear viscosity coefficient to recently introduced transport rate is derived within relativistic kinetic theory. We calculate over entropy ratio $\ensuremath{\eta}/s$ for a gluon gas, which involves elastic $gg\ensuremath{\rightarrow}gg$ perturbative QCD (PQCD) scatterings as well inelastic $gg\ensuremath{\leftrightarrow}ggg$ PQCD bremsstrahlung. For ${\ensuremath{\alpha}}_{s}=0.3$ we find $\ensuremath{\eta}/s=0.13$ and ${\ensuremath{\alpha}}_{s}=0.6$,...
To describe momentum isotropization of gluon matter produced in ultrarelativistic heavy-ion collisions, the transport rate drift and collision rates elastic ($\mathit{gg}\ensuremath{\leftrightarrow}\mathit{gg}$) as well inelastic ($\mathit{gg}\ensuremath{\leftrightarrow}\mathrm{ggg}$) perturbative quantum chromodynamics- (pQCD) scattering processes are introduced calculated within kinetic parton cascade Boltzmann approach multiparton scatterings (BAMPS), which simulates space-time evolution...
Following the procedure introduced by Israel and Stewart, we expand entropy current up to third order in shear stress tensor ${\ensuremath{\pi}}^{\ensuremath{\alpha}\ensuremath{\beta}}$ derive a novel third-order evolution equation for ${\ensuremath{\pi}}^{\ensuremath{\alpha}\ensuremath{\beta}}$. This is solved one-dimensional Bjorken boost-invariant expansion. The scaling solutions various values of viscosity density ratio $\ensuremath{\eta}/s$ are shown be very good agreement with those...
Lattice calculations of the QCD trace anomaly at temperatures $T<160$ MeV have been shown to match hadron resonance gas model calculations, which include an exponentially rising mass spectrum. In this paper we perform a more detailed comparison lattice data that confirms need for increasing density hadronic states. Also, find is compatible with states goes as $\rho(m) \sim m^{-a}\exp(m/T_H) $ large $m$ $a> 5/2$ (where $T_H 167$ MeV). With specific subleading contribution states, heavy...
We solve the relativistic Riemann problem in viscous gluon matter employing a microscopic parton cascade. demonstrate transition from ideal to shock waves by varying shear viscosity entropy density ratio eta/s zero infinity. show that an larger than 0.2 prevents development of well-defined on time scales typical for ultrarelativistic heavy-ion collisions. Comparisons with hydrodynamic calculations confirm our findings.
Employing a perturbative QCD based parton cascade we calculate the elliptic flow ${v}_{2}$ and its transverse momentum dependence ${v}_{2}({p}_{T})$ for gluon matter created in $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{{s}_{\mathit{NN}}}=200$ GeV. To make comparisons with experimental data BNL Relativistic Heavy Ion Collider (RHIC), parton-hadron duality is assumed. We find that whereas integrated matches data, (or pion) about 20--50% smaller than data. Hadronization via fragmentation...
Elastic and radiative heavy quark interactions with light partons are studied the partonic transport model named Boltzmann approach to multiparton scatterings (BAMPSs). After calculating cross section of processes for finite masses in improved Gunion–Bertsch approximation verifying this calculation by comparing exact result, we study elastic energy loss a static medium quarks gluons. Furthermore, full 3 + 1D space–time evolution gluons, quarks, ultra-relativistic heavy-ion collisions at BNL...
We demonstrate that the diffusion currents do not depend only on gradients of their corresponding charge density, but different are coupled. This happens in such a way it is possible for density given to generate dissipative another charge. Within this scheme, coefficient best viewed as matrix, which diagonal terms correspond usual coefficients, while off-diagonal describe coupling between currents. In Letter, we calculate first time complete matrix hot and dense nuclear matter, including...
We derive multicomponent relativistic second-order dissipative fluid dynamics from the Boltzmann equations for a reactive mixture of ${N}_{\mathrm{spec}}$ particle species with ${N}_{q}$ intrinsic quantum numbers (e.g., electric charge, baryon number, and strangeness) using method moments. obtain continuity multiple conserved charges as well conservation total energy momentum in single-fluid approximation. These $4+{N}_{q}$ laws are closed by deriving motion quantities $(10+4{N}_{q})$-moment...