1109.3621 (Philip Rau et al.)

Baryon Resonances in a Chiral Hadronic Model for the QCD Equation of
State    [PDF]

Philip Rau, Jan Steinheimer, Stefan Schramm, Horst Stöcker

In this paper we study the influence of hadronic resonances on the phase
diagram calculated with an effective chiral flavour SU(3) model. We show that
varying the couplings of the baryonic resonances to the attractive scalar and
the repulsive vector fields has a major impact on the order and location of the
chiral phase transition and the possible existence of a critical end point as
well as on the thermodynamic properties of the model. Furthermore, we study
(strange) quark number fluctuations and show the related susceptibilities both
at zero baryochemical potential and when crossing the phase transition line at
three different points in the T-mu plane. We obtain the best agreement with
current lattice data if we choose a rather strong vector coupling which in our
model limits the phase transition to a smooth crossover and implies the
non-existence of a critical end point.

View original: http://arxiv.org/abs/1109.3621