Ultra-peripheral Au+Au collisions at PHENIX

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.

5 pages, 3 figures, presented at the XVII International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2009). The presentation was supported by the OTKA grant NK73143

References in corpus (3)

• The Physics of Ultraperipheral Collisions at the LHC
• Coherent gamma-gamma and gamma-A interactions in very peripheral collisions at relativistic ion colliders
• Photoproduction of J/psi and of high mass e+e- in ultra-peripheral Au+Au collisions at sqrt(s_NN) = 200 GeV