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arXiv · 1709.07612

Thermal quarkonium physics in the pseudoscalar channel

Y. Burnier·H. -T. Ding·O. Kaczmarek·A. -L. Kruse·M. Laine·H. Ohno·H. Sandmeyer
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Abstract

The pseudoscalar correlator is an ideal lattice probe for thermal modifications to quarkonium spectra, given that it is not compromised by a contribution from a large transport peak. We construct a perturbative spectral function incorporating resummed thermal effects around the threshold and vacuum asymptotics above the threshold, and compare the corresponding imaginary-time correlators with continuum-extrapolated lattice data for quenched SU(3) at several temperatures. Modest differences are observed, which may originate from non-perturbative mass shifts or renormalization factors, however no resonance peaks are needed for describing the quenched lattice data for charmonium at and above T ~ 1.1Tc ~ 350 MeV. For comparison, in the bottomonium case a good description of the lattice data is obtained with a spectral function containing a single thermally broadened resonance peak.

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Y. Burnier, H. -T. Ding, O. Kaczmarek, A. -L. Kruse, M. Laine, H. Ohno, H. Sandmeyer. 2017-09-22. Thermal quarkonium physics in the pseudoscalar channel. https://doi.org/10.1007/jhep11(2017)206

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