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arXiv · 2004.09649

Topological susceptibility in QCD with two flavors and 3-5 colors -- a pilot study

Thomas DeGrand
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Abstract

I present a calculation of the topological susceptibility $\chi_T$ in $SU(N_c)$ gauge theory with $N_c=3-5$ colors and $N_f=2$ degenerate flavors of fermions. The results lie on a common curve when expressed in terms of the combination $N_c m_{PS}^2 t_0$ where $m_{PS}$ is the pseudoscalar meson mass and $t_0$ is the flow parameter. $\chi_T$ approaches its quenched value as the pseudoscalar mass becomes large. The lattice simulations use clover fermions. They are done at a single lattice spacing, roughly matched across $N_c$, and over a restricted range of fermion masses.

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Thomas DeGrand. 2020-04-20. Topological susceptibility in QCD with two flavors and 3-5 colors -- a pilot study. https://doi.org/10.1103/physrevd.101.114509

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