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arXiv · 1110.3152

Chiral phase transition at finite temperature and conformal dynamics in large Nf QCD

Kohtaroh Miura·Maria Paola Lombardo·Elisabetta Pallante
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Abstract

We investigate the chiral phase transition at finite temperature (T) in colour SU(Nc=3) Quantum Chromodynamics (QCD) with six species of fermions (Nf=6) in the fundamental representation by using lattice QCD with improved staggered fermions. By considering lattices with several temporal extensions Nt, we observe asymptotic scaling for Nt > 4. We then extract the dimensionless ratio Tc/Lambda_L (Lambda_L = Lattice Lambda-parameter) for Nf = 6 and Nf = 8, the latter relying on our earlier results. Further, we collect the critical couplings beta^c for the chiral phase transition at Nf = 0 (quenched), and Nf = 4 at a fixed Nt = 6. The results are consistent with enhanced fermionic screening at larger Nf. The Tc/Lambda_L depends very mildly on Nf in the Nf = 0 - 4 region, starts increasing at Nf = 6, and becomes significantly larger at Nf = 8, close to the edge of the conformal window. We discuss interpretations of these results as well as their possible interrelation with preconformal dynamics in the light of a functional renormalization group analysis.

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Kohtaroh Miura, Maria Paola Lombardo, Elisabetta Pallante. 2012-03-09. Chiral phase transition at finite temperature and conformal dynamics in large Nf QCD. https://doi.org/10.1016/j.physletb.2012.03.017

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