arXiv subjects

Peter Levai

Publications and source records attributed to Peter Levai.

22 records · Page 2Linked to original sources

arXiv1998

Jet Quenching and Cronin Enhancement in A+A at s^1/2=20 vs 200 AGeV

The sensitivity of semi-hard (p_\perp < 10 GeV) hadron production to parton energy loss in high energy nuclear collisions is studied via the HIJING1.35 model. We test the model on recent WA98 data on 160 AGeV Pb+Pb -> pi^0 up to 4 GeV/c and while these data are reproduced, the results depends sensitively on the model of the Cronin effect. At (RHIC) collider energies (s^1/2 > 200 AGeV), on the other hand, semi-hard hadron production becomes insensitive to the above model and is thus expected to be a cleaner probe of jet quenching signature associated with non-Abelian radiative energy loss.

hep-ph↗

arXiv1997

Massive gluons and quarks and the equation of state obtained from SU(3) lattice QCD

We analyze recent results of SU(3) lattice QCD calculations with a phenomenological parametrization for the quark-gluon plasma equation of state based on a quasi-particle picture with massive quarks and gluons. At high temperature we obtain a good fit to the lattice data using perturbative thermal quark and gluon masses from an improved HTL scheme. At temperatures close to the confinement phase transition the fitted masses increase above the perturbative value, and a non-zero (but small) bag constant is required to fit the lattice data.

hep-ph↗

arXiv1997

Thermal charm production by massive gluons and quarks

We investigate charm production in an equilibrated quark-gluon plasma produced in heavy-ion collisions at RHIC and LHC. Effective quark and gluon masses are introduced from thermal QCD calculations. Assuming a Bjorken-type longitudinal expansion and including the influence of temperature dependent masses on the expansion, we determine the total number of c\bar{c} pairs produced in the quark-gluon plasma phase. We calculate the charm production rate at leading order with massive gluons and quarks and compare our result to charm production by massless partons. We consider two different scenarios for the initial conditions, a parton gas with a rather long kinetic equilibration time and a minijet gas with a short equilibration time. In a parton gas, assuming m_c=1.2 GeV, we obtain a substantial enhancement over the thermal charm rate from massless quarks and gluons, up to 4.9 secondary charm quark pairs in Au+Au collisions at RHIC and 245 charm pairs in Pb+Pb collisions at the LHC.

hep-ph↗

arXiv1994

Open Charm Production in an Equilibrating Parton Plasma

Open charm production during the equilibration of a gluon dominated parton plasma is calculated, with both the time-dependent temperature and parton densities given by a set of rate equations. Including pre-thermal production, the total enhancement of open charm production over the initial gluon fusion depends sensitively on the initial parton density and the effective temperature. The dependence of the pre-thermal charm production on the space-momentum correlation in the initial parton phase-space distribution is also discussed.

hep-ph↗