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arXiv · 0907.4856

Ultra-peripheral Au+Au collisions at PHENIX

Mate Csanad
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Abstract

Ultra-peripheral collisions (UPC) of heavy-ions involve long range electromagnetic interactions at impact parameters twice larger than the nuclear radius, where no nucleon-nucleon collisions occur. The first measurement of photoproduction of $J/\psi$ and of two-photon production of high-mass $e^+ e^-$ pairs in ultra-peripheral nucleus-nucleus interactions will be presented, using Au+Au data at $\sqrt{s_{_{NN}}}$ = 200 GeV. The measured cross sections at midrapidity are consistent with various theoretical predictions.

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Mate Csanad. 2009-07-28. Ultra-peripheral Au+Au collisions at PHENIX. https://arxiv.org/abs/0907.4856

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