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Dissociation of a Heavy Quarkonium at T<T_c

Cheuk-Yin Wong·Ted Barnes·Eric S. Swanson·Horace W. Crater
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Abstract

We examine three different ways a heavy quarkonium can dissociate at temperatures below the quark-gluon plasma phase transition temperature T_c: spontaneous dissociation, dissociation by thermalization, and dissociation by collision with hadrons. We evaluate the cross sections for the dissociation of J/psi and Upsilon in collision with pion as a function of temperature, using the quark-interchange model of Barnes and Swanson. We also evaluate the dissociation temperatures for various quarkonia, and the fraction of quarkonium lying above the dissociation threshold as a function of temperature, using an interquark potential inferred from lattice gauge calculations.

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Cheuk-Yin Wong, Ted Barnes, Eric S. Swanson, Horace W. Crater. 2002-02-20. Dissociation of a Heavy Quarkonium at T<T_c. https://arxiv.org/abs/nucl-th/0112023

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