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arXiv · 0901.2757

J/psi Transverse Momentum Distribution in High Energy Nuclear Collisions

Yunpeng Liu·Zhen Qu·Nu Xu·Pengfei Zhuang
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Abstract

The transverse momentum (pt) dependence of J/psi production in heavy ion collisions is investigated in a transport model with both initial production and continuous regeneration of charmonia. The competition between the two production mechanisms results in a pt suppression in central collisions, the gluon multi-scattering in the initial stage leads to a high pt enhancement, and the regeneration populates J/psis at low pt region and induces a minimum in R_AA(pt). These three phenomena are indeed observed in both 200 GeV Cu+Cu and Au+Au collisions at RHIC energy.

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Yunpeng Liu, Zhen Qu, Nu Xu, Pengfei Zhuang. 2009-06-12. J/psi Transverse Momentum Distribution in High Energy Nuclear Collisions. https://doi.org/10.1016/j.physletb.2009.06.006

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