The determination of the hot QCD pressure has a long history, and has --
due to its phenomenological relevance in cosmology, astrophysics and heavy-ion collisions — spawned a number of important theoretical advances in perturbative thermal field theory applicable to equilibrium thermodynamics.
In particular, the long-standing infrared problem that obstructs the perturbative series has been...
Effective models play an important role in the investigation of the phase structure of the strongly interacting matter. Such an effective model is the (axial) vector meson extended linear sigma model (ELSM), which was already analyzed at finite temperature and gave predictions to thermodynamical quantities in good agreement with current lattice results. Recently, several advancements were done...
We discuss mean field theory of Quarkyonic matter at zero temperature. this field theoretical description of quarkyonic matter consisting of quark, nucleon and ghost fields. The ghosts are present to cancel over-counting of nucleon states that are Pauli blocked by the quark Fermi sea. We treat the nucleons with contact interactions in mean field approximation and the quarks without mean field...
High-pt theory and data are traditionally used to explore high-pt parton interactions with QGP, while bulk QGP properties are commonly explored through low-pt data. However, rare high-pt light and heavy flavor can also be a powerful tool for inferring bulk QGP properties, as they are sensitive to global QGP parameters. A prerequisite for such QGP tomography is a proper description of high-pt...
The BEST collaboration’s equation of state (EoS) maps a 3D Ising model onto the lattice QCD EoS but contains 4 free parameters related to the size, location, and spread of the critical region across the QCD phase diagram. However, certain combinations of those 4 free parameters lead to acausal ($c_s^2>1$) or unstable ($\chi_2^B<0$) realizations of the EoS that should not be considered. Here,...
The HADES experiment at GSI has recently provided data on the flow coefficients $v_1,...,v_4$ for protons in Au+Au reactions at $E_{\rm lab} = 1.23$ $A$GeV (or $\sqrt{s_\mathrm{NN}}=2.4$ GeV). This data allows to estimate the shear viscosity over entropy density ratio, $\eta/s$, at low energies via a coarse graining analysis of the UrQMD transport simulations of the flow harmonics in...
Spin Hall effect (SHE) is a generation of spin polarization for moving spin carriers in material under an external electric field. Recent theoretical analyses show that spin Hall current can be induced by the baryon chemical potential $\mu_{B}$ gradient[1], which plays role of the analogous electric field and becomes sizable at the beam scan energies of RHIC .
We study and predict this SHE...
Bulk matter produced in heavy ion collisions has multiple
conserved quantum numbers like baryon number, strangeness and electric charge. The diffusion process
of these charges can be described by a diffusion matrix describing the interdependence of diffusion of
different charges. The diffusion coefficient matrix is estimated here from the Boltzmann kinetic theory
for the hadronic phase...
Understanding the impact of strong magnetic fields on QCD dynamics is important for an accurate description of non-central heavy-ion collisions and neutron stars. Lattice simulations found that a finite magnetic field affects the chiral dynamics of QCD in a non-trivial way. At low temperatures, the magnitude of chiral condensate increases with the magnetic field, the phenomenon known as the...
QCD with heavy dynamical quarks exhibits a first order thermal transition which is driven by the spontaneous breaking of the global $\mathcal{Z}_3$ center symmetry. Decreasing the quark masses weakens the transition until the corresponding latent heat vanishes at the critical mass.
We explore the heavy mass region with three flavors of staggered quarks and analyze the Polyakov loop and its...
Thermal photons from the QGP provide important information about the interaction among the plasma constituents. The thermal photon production rate from a thermally equilibrated plasma is proportional to the transverse spectral function $\rho_{T}(k_0=|\vec k|,\vec k)$. One can calculate the photon production rate also from the difference between $\rho_{T}$ and $\rho_{L}$(longitudinal)...
The thermal fit to preliminary HADES data of Au+Au collisions at $\sqrt{s_{_{NN}}}=2.4$ GeV shows two degenerate solutions at $T\approx 50$ MeV and $T\approx 70$ MeV. The analysis of the same particle yields in a transport simulation of the UrQMD model yields the same features, i.e. two distinct temperatures for the chemical freeze-out. While both solutions yield the same number of hadrons...
Motivated by the quark-gluon plasma, we develop a simulation method to obtain the spectral function of fermions non-perturbatively in a non-Abelian gauge theory with large gluon occupation numbers. We apply our method to a non-Abelian plasma close to a far-from-equilibrium self-similar regime, and find very good agreement with perturbative hard loop (HTL) calculations for medium-induced...
Fluctuations of conserved charges, in particular the baryon number fluctuations, are thought of as experimental observables which are sensitive to the QCD critical end point (CEP), where the singular part of thermodynamic functions plays a dominant role. Indeed, in the past several years significant fluctuation measurements have been performed in the Beam Energy Scan program at RHIC, and an...
