Ginzburg-Landau approach to the QCD phase-diagram / Stephan Stetina
VerfasserStetina, Stephan
Begutachter / BegutachterinRebhahn, Anton ; Schmitt, Andreas
Umfang57 Bl. : graph. Darst.
HochschulschriftWien, Techn. Univ., Dipl.-Arb., 2010
Schlagwörter (DE)Ginzburg Landau - Phasendiagramm - QCD
Schlagwörter (EN)Ginzburg Landau - phasediagram - QCD
URNurn:nbn:at:at-ubtuw:1-39906 Persistent Identifier (URN)
 Das Werk ist frei verfügbar
Ginzburg-Landau approach to the QCD phase-diagram [1.05 mb]
Zusammenfassung (Englisch)

We discuss the phase structure of dense matter, in particular the nature of the transition between hadronic and quark matter.

Calculations within a Ginzburg-Landau approach show that the axial anomaly can induce a critical point in this transition region. This is possible because in three-flavor quark matter with instanton effects a chiral condensate can be added to the color-flavor locked (CFL) phasewithout changing the symmetries of the ground state. In two-flavor quark matter such a critical point is not possible since the corresponding color superconductor (2SC) does not break chiral symmetry. We study the effects of a nonzero but finite strange quark mass which interpolates between these two cases. Since at ultra-high density the first reaction of CFL to a nonzero strange quark mass is to develop a kaon condensate, we extend previous Ginzburg-Landau studies by including such a condensate. We discuss the fate of the critical point systematically and show that the continuity between hadronic and quark matter can be disrupted by the onset of a kaon condensate. Moreover, we identify the mass terms in the Ginzburg-Landau potential which are needed for the 2SC phase to occur in the phase diagram.