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arXiv · 1811.02494

QCD phase diagram for finite imaginary chemical potential with HISQ fermions

Jishnu Goswami·Frithjof Karsch·Anirban Lahiri·Christian Schmidt
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Abstract

We present results from an ongoing study of the phase diagram of (2+1)-flavor QCD using the HISQ action with smaller than physical light quark masses in the Roberge-Weiss (RW) plane on lattices with temporal extent $N_\tau=4$. We find that the endpoint of the $1^{st}$ order RW transition line remains $2^{nd}$ order at least down to light quark masses corresponding to Goldstone pion masses of $55$ MeV. Furthermore, we show that the chiral condensate is sensitive to the RW transition and may serve as a energy-like operator characterizing universal behavior close to the RW endpoint.

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Jishnu Goswami, Frithjof Karsch, Anirban Lahiri, Christian Schmidt. 2018-11-06. QCD phase diagram for finite imaginary chemical potential with HISQ fermions. https://doi.org/10.22323/1.334.0162

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