CHIRAL AND UA(1) PHASE TRANSITIONS IN π0, η AND η′ MESONS
21 Jun 2006-Modern Physics Letters A (World Scientific Publishing Company)-Vol. 21, Iss: 19, pp 1529-1539
TL;DR: In this article, the authors generalized the Pisarsky-Wilczek model of studying the UA(1) phase transition in π0, η and η′ system by incorporating the chiral phase transition.
Abstract: We have generalized the Pisarsky–Wilczek model of studying the UA(1) phase transition in π0, η and η′ system by incorporating the chiral phase transition. The mass-squared matrix of the neutral pseudoscalar mesons is revisited explicitly from the chiral effective action which necessitates the mixing among the unmixed states to get the physical states. The derivation of the mass spectra of the neutral pseudoscalar mesons shows that apart from their masses, the mixing angles also become temperature dependent. Based on the dilute instanton gas approximation we show that, the UA(1) phase transition along with the chiral phase transition plays an important role in the process of hadronization of the quark–gluon plasma with the quarks of three flavors.
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