Recent lattice QCD calculations, at physical pion masses and small lattice spacings that approach the continuum limit, have revealed that non-diagonal quark correlators above the critical temperature are nite up to about 2 Tc. Since the transition from hadronic to free partonic degrees of freedom is merely an analytic cross-over, it is likely that, in the temperature regime between 1-2 Tc, quark and gluon quasiparticles and pre-hadronic bound states can coexist. The correlator values, in comparison to PNJL model calculations beyond mean-eld, indicate that at least part of the mixed phase resides in color-neutral bound states. A similar eect was postulated for the in-medium fragmentation process, i.e. for partons which do not thermalize with the system and thus constitute the non-equilibrium component of the particle emission spectrum from a deconned plasma phase. Here, for the rst time we investigate the likelihood of forming bound states also in the equilibrated, parton dominated phase above Tc which is described by lattice QCD.
Are there hadronic bound states above the QCD transition temperature?
Cristoforetti, Marco;
2012-01-01
Abstract
Recent lattice QCD calculations, at physical pion masses and small lattice spacings that approach the continuum limit, have revealed that non-diagonal quark correlators above the critical temperature are nite up to about 2 Tc. Since the transition from hadronic to free partonic degrees of freedom is merely an analytic cross-over, it is likely that, in the temperature regime between 1-2 Tc, quark and gluon quasiparticles and pre-hadronic bound states can coexist. The correlator values, in comparison to PNJL model calculations beyond mean-eld, indicate that at least part of the mixed phase resides in color-neutral bound states. A similar eect was postulated for the in-medium fragmentation process, i.e. for partons which do not thermalize with the system and thus constitute the non-equilibrium component of the particle emission spectrum from a deconned plasma phase. Here, for the rst time we investigate the likelihood of forming bound states also in the equilibrated, parton dominated phase above Tc which is described by lattice QCD.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
