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arXiv · 1407.8080

Charmonium in a hot medium: melting vs absorption

B. Z. Kopeliovich·I. K. Potashnikova·Ivan Schmidt·M. Siddikov
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Abstract

A charmonium produced in heavy ion collisions at RHIC and LHC propagates through a dense co-moving matter with a rather high relative momentum, =4-10GeV^2. In spite of Debye screening of the binding potential, the charmonium survives with a substantial probability, even if the c-cbar potential is completely screened in the hot environment. In addition, the color-exchange interaction with the medium is another important source of charmonium suppression. Attenuation in a hot medium caused by both effects is evaluated by means of the path integral technique, which requires ability of boosting the binding potential to a moving reference frame. This problem is solved in the approximation of small intrinsic velocities of the charmed quarks.

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B. Z. Kopeliovich, I. K. Potashnikova, Ivan Schmidt, M. Siddikov. 2014-08-11. Charmonium in a hot medium: melting vs absorption. https://doi.org/10.1016/j.nuclphysa.2014.08.043

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