Dilepton production in finite baryonic quark–gluon plasma

Abstract

We study the evolution of hot plasma through a statistical model in the hadronic medium. Evolution of the plasma can be expressed by the free energy at finite temperature and quark chemical potential of the constituent particles in the system. In this study, the dynamical quark mass is dependent on momentum and temperature. The evolution is explained through thermodynamic variables like free energy and entropy curve. These variables show the behaviour of the system for the different chemical potentials, m, at these transition temperatures T = 150-170 MeV. Moreover, the study of the dilepton production at these finite temperatures and quark chemical potentials from the fireball of quark-gluon plasma shows a specific structure of dilepton spectrum in the intermediate mass region of 1.0-4.0 GeV and its production rate is observed to be a strong increasing function of quark chemical potential for quark and antiquark annihilation. We further observe lepton spectra coming from the hadronic phase in the low mass M = 0-1.2 GeV region.PACS Nos: 25.75.Ld, 12.38.Mh, 21.65.+f Résumé : Via un modèle statistique, nous étudions l'évolution d'un plasma chaud dans un milieu hadronique. L'évolution du plasma peut s'exprimer à l'aide de l'énergie libre à température finie et du potentiel chimique des constituants du plasma. Ici, la masse dynamique du quark dépend de la quantité de mouvement et de la température. L'évolution s'explique à l'aide des variables thermodynamiques comme l'énergie libre et la courbe d'entropie. Ces variables décrivent le comportement du système pour les différents potentiels chimiques, µ, aux températures de transition, T = 150-170 MeV. De plus la production de di-leptons, à cette température finie et avec ce potentiel chimique de quark venant de la boule de feu de plasma quark-gluon, montre une structure spécifique de spectre de di-lepton dans la région de masse intermédiaire 1,0-4,0 GeV et nous observons que son taux de production est une fonction croissante du potentiel chimique des quarks pour l'annihilation quark-antiquark. Nous étudions également le spectre de leptons provenant de la phase hadronique, M = 0-1,0 GeV.[Traduit par la Rédaction]

Free Energy Evolution and Photon Radiation from QGP

“…So, quark mass is used in removing the IR divergence and it is initially handled by the technique of [32][33][34]. So, we consider the thermal finite quark mass as [35]…”

Effect of Magnetic Field on Dilepton Production Rate in Relativistic Heavy Ion Collisions

“…It is believed that there exists non-zero chemical potential in the early stage of the plasma. This information prompted Dumitru et al to express dilepton emission rate as a function of temperature and quark chemical potential μ of the QGP [24]. We define quark mass which depends on temperature and chemical potential and it is expressed as, where g 2 = 4πα s is the QCD coupling factor and the value of α s is given as,…”

Dilepton production in thermal-dependent baryonic quark–gluon plasma

“…v qq is the relative velocity of the annihilating quark pair and p is lepton pair four momentum (M 2 = p p lepton pair mass). qq ¡ ll¯i s the electromagnetic annihilation cross section [18]. Then we substituted the distribution functions for quark and antiquark into (11) using (1), and integrating over q and q momentum, we obtain dilepton emission rate at TDCP as…”

“…Now, we consider the massless dynamical quark as a finite value called thermaldependent quark mass (TDQM) obtained through the parametrization value and temperature. The finite value of the quark mass is defined as [18] m q…”