Latest documents http://publikationen.ub.uni-frankfurt.de/index/index/ Wed, 23 Nov 2005 09:19:04 +0100 Wed, 23 Nov 2005 09:19:04 +0100 http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/3186 Compelling evidence for a new form of matter has been claimed to be formed in Pb+Pb collisions at SPS. We critically review two suggested signatures for this new state of matter: First the suppression of the J/psi , which should be strongly suppressed in the QGP by two different mechanisms, the color-screening [1] and the QCD-photoe ect [2]. Secondly the measured particle, in particular strange hadronic, ratios might signal the freeze-out from a quark-gluon phase. Detlef Zschiesche; Lars Gerland; Stefan Schramm; Jürgen Schaffner-Bielich; Horst Stöcker; Walter Greiner preprint http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/3186 Wed, 23 Nov 2005 09:19:04 +0100 http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/3324 We evaluate the in-medium D and -meson masses in hot hadronic matter induced by interactions with the light hadron sector described in a chiral SU(3) model. The e ective Lagrangian approach is generalized to SU(4) to include charmed mesons. We find that the D-mass drops substantially at finite temperatures and densities, which open the channels of the decay of the charmonium states ( 2, c, J/ ) to D pairs in the thermal medium. The e ects of vacuum polarisations from the baryon sector on the medium modification of the D-meson mass relative to those obtained in the mean field approximation are investigated. The results of the present work are compared to calculations based on the QCD sum-rule approach, the quark-meson coupling model, chiral perturbation theory, as well as to studies of quarkonium dissociation using heavy quark potential from lattice QCD. Amruta Mishra; Elena L. Bratkovskaya; Jürgen Schaffner-Bielich; Stefan Schramm; Horst Stöcker preprint http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/3324 Thu, 10 Nov 2005 10:34:59 +0100