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arXiv · 1806.05301

Localization of topological charge density near $T_c$ in quenched QCD with Wilson flow

You-Hao Zou·Jian-Bo Zhang·Guang-Yi Xiong
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Abstract

We smear quenched lattice QCD ensembles with lattice volume $32^3\times 8$ by using Wilson flow. Six ensembles at temperature near the critical temperature $T_c$ corresponding to the critical inverse coupling $\beta_c=6.06173(49)$ are used to investigate the localization of topological charge density. If the effective smearing radius of Wilson flow is large enough, the density, size and peak of Harrington-Shepard (HS) caloron-like topological lumps of ensembles are stable when $\beta\leq 6.050$, but start to change significantly when $\beta\geq6.055$. The inverse participation ratio (IPR) of topological charge density shows similar results, it begins to increase when $\beta\geq 6.055$ and is stable when $\beta\leq 6.050$. The pseudoscalar glueball mass is extracted from the topological charge density correlator (TCDC) of ensembles at $T=1.19T_c,~\textrm{and }1.36T_c$, the masses are $1.915(98)\textrm{ GeV}$ and $1.829(123)\textrm{ GeV}$ respectively, they are consistent with results from conventional methods.

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You-Hao Zou, Jian-Bo Zhang, Guang-Yi Xiong. 2018-06-13. Localization of topological charge density near $T_c$ in quenched QCD with Wilson flow. https://doi.org/10.1103/physrevd.98.014504

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