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arXiv · 1901.02294

Measuring of chiral susceptibility using gradient flow

Atsushi Baba·Shinji Ejiri·Kazuyuki Kanaya·Masakiyo Kitazawa·Takanori Shimojo·Asobu Suzuki·Hiroshi Suzuki·Yusuke Taniguchi·Takashi Umeda
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Abstract

In lattice QCD with Wilson-type quarks, the chiral symmetry is explicitly broken by the Wilson term on finite lattices. Though the symmetry is guaranteed to recover in the continuum limit, a series of non-trivial procedures are required to recover the correct renormalized theory in the continuum limit. Recently, a new use of the gradient flow technique was proposed, in which correctly renormalized quantities are evaluated in the vanishing flow-time limit. This enables us to directly study the chiral condensate and its susceptibility with Wilson-type quarks. Extending our previous study of the chiral condensate and its disconnected susceptibility in (2+1)-flavor QCD at a heavy $u$, $d$ quark mass ($m_π/m_ρ\simeq0.63$) and approximately physical $s$ quark mass, we compute the connected contributions to the chiral susceptibility in the temperature range of 178--348 MeV on a fine lattice with $a\simeq0.07$ fm.

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Atsushi Baba, Shinji Ejiri, Kazuyuki Kanaya, Masakiyo Kitazawa, Takanori Shimojo, Asobu Suzuki, Hiroshi Suzuki, Yusuke Taniguchi, Takashi Umeda. 2019-01-08. Measuring of chiral susceptibility using gradient flow. https://arxiv.org/abs/1901.02294

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