We discuss nuclear broadening of the intrinsic transverse momentum of partons in the initial state, and its influence on the pt distribution of prompt photons. Comparing to WA98 data from Pb+Pb collisions at vs = 17.4A GeV we find evidence for the presence of nuclear broadening at high pt in this hard process. Below pt ~ 2.7 GeV the photon distribution is due to small momentum transfer processes. At RHIC energy, s = 200A GeV, the effect of intrinsic transverse momentum on the spectrum of prompt photons is less prominent. Below pt = 2 - 3 GeV the contribution from large momentum transfers flattens out, and we expect that region to be dominated by soft contributions.
|Original language||English (US)|
|Journal||Proceedings of Science|
|Publication status||Published - Jan 1 2001|
|Event||2001 International Europhysics Conference on High Energy Physics, HEP 2001 - Budapest, Hungary|
Duration: Jul 12 2001 → Jul 18 2001
All Science Journal Classification (ASJC) codes