PHENIX has measured the centrality dependence of charged hadron pT spectra from Au + Au collisions at sNN√ = 130 GeV. The truncated mean pT decreases with centrality for pT > 2 GeV/c, indicating an apparent reduction of the contribution from hard scattering to high pT hadron production. For central collisions the yield at high pT is shown to be suppressed compared to binary nucleon-nucleon collision scaling of p + p data. This suppression is monotonically increasing with centrality, but most of the change occurs below 30% centrality, i.e., for collisions with less than ∼ 140 participating nucleons. The observed pT and centrality dependence is consistent with the particle production predicted by models including hard scattering and subsequent energy loss of the scattered partons in the dense matter created in the collisions.
|Number of pages||11|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 2003 May 22|
Bibliographical noteFunding Information:
We thank the staff of the Collider-Accelerator and Physics Departments at BNL for their vital contributions. We acknowledge support from the Department of Energy and NSF (USA), MEXT and JSPS (Japan), RAS, RMAE, and RMS (Russia), BMBF, DAAD, and AvH (Germany), VR and KAW (Sweden), MIST and NSERC (Canada), CNPq and FAPESP (Brazil), IN2P3/CNRS (France), DAE and DST (India), KRF and CHEP (Korea), the US CRDF for the FSU, and the US-Israel BSF.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics