2008/12/16 by Daniël Boer, Jorn K. Boomsma, Daniel Boer
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1016/j.nuclphysa.2009.01.062
published as Nucl.Phys.A820:251c-254c,2009; PoS Confinement8:134,2008 · 5 pages, 7 figures; talk given at the 8th Conference "Quark Confinement and the Hadron Spectrum", Mainz, Germany, 1-6 September 2008
arxiv created 2008/12/16 · openalex publication_date 2009/03/19 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
As is well-known, spontaneous CP-violation in the strong interaction is possible at theta = pi, which is commonly referred to as Dashen's phenomenon. This phenomenon has been studied extensively using chiral Lagrangians. Here the two-flavor NJL model at theta = pi is discussed. It turns out that the occurrence of spontaneous CP-violation depends on the strength of the 't Hooft determinant interaction, which describes the effect of instanton interactions. The dependence of the phase structure, and in particular of the CP-violating phase, on the quark masses, temperature, baryon and isospin chemical potential is examined in detail. The latter dependence shows a modification of the charged pion condensed phase first discussed by Son and Stephanov.