1. Observation of dijet-like correlations between charged pions of high-transverse momentum produced in 158 GeV/c Pb-Au collisions<br>2. A new rescatt

by Jan Rak and Stephane Peigne (Univ. of Heidelberg, LAPP, Annecy)

Tuesday 5 Dec 2000, 11:00 → 12:00 Europe/Zurich

40-S2-A01 (CERN)

Observation of dijet-like correlations between charged pions of high-transverse momentum produced in 158 GeV/c Pb-Au collisions by Jan Rak (Univ. of Heidelberg) Azimuthal correlations of high-pt charged pions produced in Pb-Au 160 A.GeV/c collisions have been studied by the CERES experiment. Anisotropies of about 10%, which cannot be accounted for by elliptic flow, are attributed to back-to-back semi-hard parton scattering. A possible interpretation of the observed pi-pairs yield in terms of partonic energy loss and pt-broadening will be discussed. A new rescattering mechanism for quarkonium production by Stephane Peigne (LAPP, Annecy) I will show how the general features of the data on quarkonium production suggest the presence of a new rescattering mechanism in hadroproduction. Extrapolation from pp to pA collisions will be qualitatively discussed.

Organiser(s): Yiota Foka, Guy Paic and Urs Wiedemann