Evidence for higher order QED effects in e+ e- pair production at the BNL Relativistic Heavy Ion Collider.
A new lowest order QED calculation for BNL Relativistic Heavy-Ion Collider e+ e- pair production has been carried out with a phenomenological treatment of the Coulomb dissociation of the heavy-ion nuclei observed in the STAR ZDC triggers. The lowest order QED result for the experimental acceptance is nearly 2 standard deviations larger than the STAR data. A corresponding higher-order QED calculation is consistent with the data.
Baltz
A J
AJ
Physics Department, Brookhaven National Laboratory, Upton, New York 11973, USA.