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arXiv · 1605.04659

Critical endline of the finite temperature phase transition for 2+1 flavor QCD around the SU(3)-flavor symmetric point

Yoshinobu Kuramashi·Yoshifumi Nakamura·Shinji Takeda·Akira Ukawa
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Abstract

We investigate the critical endline of the finite temperature phase transition of QCD around the SU(3)-flavor symmetric point at zero chemical potential. We employ the renormalization-group improved Iwasaki gauge action and non-perturbatively $O(a)$-improved Wilson-clover fermion action. The critical endline is determined by using the intersection point of kurtosis, employing the multi-parameter, multi-ensemble reweighting method to calculate observables off the SU(3)-symmetric point, at the temporal size $N_{\rm T}$=6 and lattice spacing as low as $a \approx 0.19$ fm. We confirm that the slope of the critical endline takes the value of $-2$, and find that the second derivative is positive, at the SU(3)-flavor symmetric point on the Columbia plot parametrized with the strange quark mass $m_s$ and degenerated up-down quark mass $m_{\rm l}$.

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Yoshinobu Kuramashi, Yoshifumi Nakamura, Shinji Takeda, Akira Ukawa. 2016-05-16. Critical endline of the finite temperature phase transition for 2+1 flavor QCD around the SU(3)-flavor symmetric point. https://doi.org/10.1103/physrevd.94.114507

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