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Finite Temperature Transition in Two Flavor QCD with Renormalization Group Improved Action

Y. Iwasaki·K. Kanaya·S. Sakai·T. Yoshie
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Abstract

The finite temperature transition or crossover in QCD with two degenerate Wilson quarks is investigated using a renormalization group improved action. At $β=2.0$ and 2.1 where $a^{-1} \sim 1.0-1.2$ GeV, the expectation value of the Polyakov loop and the pion screening mass on an $8^3 \times 4$ lattice vary smoothly with the hopping parameter through the transition/crossover. The quark screening mass in the high temperature phase agrees well with that in the low temperature phase calculated on an $8^4$ lattice. The smooth transition of the observables is totally different from the sharp transition found for the standard action at $β=5.0$ and 5.1 where $a^{-1}$ is also $1.0-1.2$ GeV.

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Y. Iwasaki, K. Kanaya, S. Sakai, T. Yoshie. 1994-12-10. Finite Temperature Transition in Two Flavor QCD with Renormalization Group Improved Action. https://doi.org/10.1016/0920-5632(95)00293-i

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