arXiv subjects

T. M. Hussein

Publications and source records attributed to T. M. Hussein.

3 recordsLinked to original sources

arXiv2019

Chiral phase structure and sixteen meson states in SU(3) Polyakov linear-sigma model at finite temperature and chemical potential in strong magnetic field

In characterizing the chiral phase-structure of pseudoscalars ($J^{pc}=0^{-+}$), scalars ($J^{pc}=0^{++}$), vectors ($J^{pc}=1^{--}$) and axial-vectors ($J^{pc}=1^{++}$) meson states and their dependence on temperature, chemical potential, and magnetic fields, we utilize SU($3$) Polyakov linear-sigma model (PLSM) in mean-field approximation. We first determine the chiral (non)strange quark condensates, $σ_l$ and $σ_s$ and the corresponding deconfinement order parameters, $ϕ$ and $ϕ^*$, respectively, in thermal and dense (finite chemical potential) medium and finite magnetic field. The temperature and the chemical potential characteristics of nonet meson states normalized to the lowest {\it bosonic} Matsubara frequencies are analyzed. We noticed that all normalized meson masses become temperature independent at different {\it critical} temperatures. We observe that the chiral and deconfinement phase transitions are shifted to lower {\it quasicritical} temperatures with increasing chemical potential and magnetic field. Thus, we conclude that the magnetic field seems to have almost the same effect as that of the chemical potential, especially on accelerating the phase transition, i.e. inverse magnetic catalysis. We also find that increasing chemical potential enhances the mass degeneracy of the various meson masses, while increasing the magnetic field seems to reduce the critical chemical potential, at which the chiral phase transition takes place. Our mass spectrum calculations agree well with the recent PDG compilations and PNJL, lattice QCD calculations, and QMD/UrQMD simulations.

hep-ph↗

arXiv2018

SU(3) Polyakov linear-sigma model: Magnetic properties of QCD matter in thermal and dense medium

The linear-sigma model, in which information about confining gluons is included through the Polyakov-loop potential (PLSM), is considered in order to perform a systematic study for various magnetic properties of QCD matter under extreme conditions of high temperatures and densities and finite magnetic field strengths. The introduction of magnetic field to the PLSM Lagrangian requires suitable utilization of Landau quantization, modification in the dispersion relations, and momentum-space dimension-reduction. We observed that increasing the magnetic field leads to filling-up lower Landau levels first and decreasing the number of occupied levels. We conclude that the population of Landau levels is most sensitive to the magnetic field and to the quark charges. The influences of finite magnetic field on the temperature dependence of chiral and deconfinement order-parameter(s) are studied. We present estimations for the magnetization, the magnetic susceptibility, the permeability and the catalysis properties of QCD matter as functions of temperature. The dependences of the resulting freezeout parameters, temperatures and baryon chemical potentials on the corresponding magnetic field strengths have been analyzed, as well. These calculations are compared with recent lattice QCD simulations, whenever available. We conclude that the QCD matter seems to have paramagnetic property at temperatures greater than the critical one. There is an evidence for weak diamagnetic property at low temperatures. Last but not least, we observe that the magnetic catalysis is inverse, namely the critical temperatures decrease with increasing the magnetic field.

hep-ph↗

arXiv2016

SU(3) Polyakov linear-sigma model: bulk and shear viscosity of QCD matter in finite magnetic field

Due to off-center relativistic motion of the charged spectators and the local momentum-imbalance of the participants, a short-lived huge magnetic field is likely generated, especially in relativistic heavy-ion collisions. In determining the temperature dependence of bulk and shear viscosities of the QCD matter in vanishing and finite magnetic field, we utilize mean field approximation to the SU($3$) Polyakov linear-sigma model (PLSM). We compare between the results from two different approaches; Green-Kubo correlation and Boltzmann master equation with Chapman-Enskog expansion. We find that both approaches have almost identical results, especially in the hadron phase. In the temperature dependence of bulk and shear viscosities relative to thermal entropy at the critical temperature, there is a rapid decrease in the chiral phase-transition and in the critical temperature with increasing magnetic field. As the magnetic field strength increases, a peak appears at the critical temperature ($T_c$). This can be understood from the small drop on the thermal entropy at $T_c$, which can be interpreted due to instability in the hydrodynamic flow of the quark-gluon plasma and soft statistical hadronization. It is obvious that, increasing magnetic field accelerates the transition from hadron to QGP phases (inverse catalysis), i.e., taking place at lower temperatures.

hep-ph↗