Speaker
Roberto Spighi
(Bologna)
Description
HERA-B is a fixed target experiment at the 920 GeV HERA proton beam at DESY which uses a variety nuclear targets. A di-lepton trigger can select events containing leptonic J/psi decays. During the 2002/2003 HERA-B run, 150 million di-lepton triggers and 200 million minimum bias triggers were recorded. About 300.000 leptonic J/psi decays (~170.000 J/psi -> mu^+mu^- and ~130.000 J/psi -> e^+e^-) were acquired with the di-lepton trigger. A complete study of the charmonium production (such as J/psi, psi' and chi_c states) in the negative Feynman x region (x_F), and of the J/psi polarization will be presented. Results will be given also on the nuclear dependence of charmonium production, on chi_c and psi' production and the determination of the b b-bar cross section in proton-nucleus collisions.
Primary author
Roberto Spighi
(Bologna)
