2002/05/27 by S. Lerma, S. Lerma H., S. Jesgarz +4 · 7 citations
Physics and Astronomy · #Boson #Gluon #Goldstone boson #Ground state #Hadron #High-Energy Particle Collisions Research #Meson #Particle physics #Phase transition #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum electrodynamics #Quantum mechanics #Quark #Quark–gluon plasma #Theoretical and Computational Physics #nucl-th
paper · pdf · doi:10.1103/physrevc.66.045207
published in Physical Review C 66(4) (American Institute of Physics) · 33 pages, 11 figures
arxiv created 2002/05/27 · openalex publication_date 2002/10/29 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The simplest version of a class of toy models for QCD is presented. It is a Lipkin-type model, for the quark-antiquark sector, and, for the gluon sector, gluon pairs with spin zero are treated as elementary bosons. The model restricts to mesons with spin zero and to few baryonic states. The corresponding energy spectrum is discussed. We show that ground state correlations are essential to describe physical properties of the spectrum at low energies. Quantum phase transitions are described in an effective manner, by using coherent states. The appearance of a Goldstone boson for large values of the interaction strength is discussed, as related to a collective state. The formalism is extended to consider finite temperatures. The partition function is calculated, in an approximate way, showing the convenience of the use of coherent states. The energy density, heat capacity, and transitions from the hadronic phase to the quark-gluon plasma are calculated.