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arXiv · 1504.00343

Dissipative effects on quarkonium spectral functions

Yusuf Buyukdag·Clint Young
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Abstract

Quarkonium at finite temperature is described as an open quantum system whose dynamics are determined by a potential $V_R({\bf x})$ and drag coefficient $η$, using a path integral with a non-local term. Path-integral Monte Carlo calculations determine the Euclidean Green function for this system to an accuracy greater than one part in a thousand and the maximum entropy method is used to determine the spectral function; challenges facing any kind of deconvolution are discussed in detail with the aim of developing intuition for when deconvolution is possible. Significant changes to the quarkonium spectral function in the $1S$ channel are found, suggesting that any description of quarkonium at finite temperature, using a potential, must also carefully consider the effect of dissipation.

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Yusuf Buyukdag, Clint Young. 2015-04-01. Dissipative effects on quarkonium spectral functions. https://doi.org/10.1103/physrevc.91.045204

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