The properties of compact stars are mainly determined by two fundamental forces: Quantum chromodynamics (QCD) and general relativity. Relativistic hydrodynamical simulations of collapsing neutron stars and binary neutron star mergers depend strongly on the high density properties of the equation of state (EoS) of hadronic and quark matter. The appearance of the QCD – phase transition (the transition from confined hadronic to deconfined quark matter) will change the properties of neutron stars; eg. usually it is assumed that the loss of stability of a neutron star, exceeding its maximum mass, leads to the collapse into a black hole. However, realistic calculations within QCD-motivated models show that a neutron star collapse could be stopped before the black hole forms. Within such a collapse scenario the neutron star would be transformed into a hybrid star with a deconfined quark matter phase at its inner core. Several astrophysical observables of the Quark-Gluon-Plasma (QGP) will be discussed during the talk. Whether these observables will be visible with telescopes and gravitational wave detectors depends strongly on the EoS and on the order and construction of the phase transition.
I.N. Mishustin, M. Hanauske, A. Bhattacharyya, L.M. Satarov, H. Stöcker, and W. Greiner; Catastrophic rearrangement of a compact star due to quark core formation; Physics Letters B 552 (2003) p.1-8 arxiv.org: hep-ph/0210422
Igor Shovkovy, Matthias Hanauske, and Mei Huang; Nonstrange hybrid compact stars with color superconducting matter; Phys. Rev. D 67 103004 (2003) arxiv.org: hep-ph/0303027
Matthias Hanauske; How to detect the Quark-Gluon-Plasma with telescopes; GSI Annual Report 2003 p.96 GSI Report 2003
A. Bhattacharyya, S.K. Ghosh, M. Hanauske, and W. Raha; Rotating Twin Stars and Signature of Quark-Hadron Phase Transition; Astron.Astrophys. 418 (2004) 795-799 arxiv.org: astro-ph/0406509
Matthias Hanauske; Dissertation: Properties of Compact Stars within QCD-motivated Models; University Library Publication 2004 UB Frankfurt
Sarmistha Banik, Matthias Hanauske and Debades Bandyopadhyay; Strange matter in rotating compact stars; J.Phys. G 31 p. 841-848 (2005) arxiv.org: nucl-th/0412110