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arXiv · 1611.02413

Temperature dependence of topological susceptibility using gradient flow

Yusuke Taniguchi·Shinji Ejiri·Kazuyuki Kanaya·Masakiyo Kitazawa·Hiroshi Suzuki·Takashi Umeda·Ryo Iwami·Naoki Wakabayashi
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Abstract

We study temperature dependence of the topological susceptibility with the $N_{f}=2+1$ flavors Wilson fermion. We have two major interests in this paper. One is a comparison of gluonic and fermionic definitions of the topological susceptibility. Two definitions are related by the chiral Ward-Takahashi identity but their coincidence is highly non-trivial for the Wilson fermion. By applying the gradient flow both for the gauge and quark fields we find a good agreement of these two measurements. The other is a verification of a prediction of the dilute instanton gas approximation at low temperature region $T_{pc}< T<1.5T_{pc}$, for which we confirm the prediction that the topological susceptibility decays with power $\chi_{t}\propto(T/T_{pc})^{-8}$ for three flavors QCD.

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Yusuke Taniguchi, Shinji Ejiri, Kazuyuki Kanaya, Masakiyo Kitazawa, Hiroshi Suzuki, Takashi Umeda, Ryo Iwami, Naoki Wakabayashi. 2016-11-08. Temperature dependence of topological susceptibility using gradient flow. https://arxiv.org/abs/1611.02413

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