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arXiv · 1903.05633

Fate of the $η'$ in the Quark Gluon Plasma

Andrey Yu. Kotov·Maria Paola Lombardo·Anton M. Trunin
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Abstract

In this paper we study the $η'$ in $N_f=2+1+1$ lattice QCD simulations at finite temperature. Results are obtained from the analysis of the gluonic defined topological charge density correlator after gradient flow. Our results indicate the growth of the $η'$ mass above the pseudocritical temperature, associated with the chiral symmetry restoration. In the vicinity of the pseudocritical temperature the results are consistent with a small dip in the $η'$ mass. The magnitude of the dip is compatible with the reduction of the $η'$ mass obtained by experimental analysis and suggests that $η'$ mass comes close to zero temperature non-anomalous contribution.

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Andrey Yu. Kotov, Maria Paola Lombardo, Anton M. Trunin. 2019-05-29. Fate of the $η'$ in the Quark Gluon Plasma. https://doi.org/10.1016/j.physletb.2019.05.035

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