The J/psi decay angular distributions have been measured in inelastic photoproduction in ep collisions with the ZEUS detector at HERA, using an integrated luminosity of 468 pb(-1). The range in photon-proton centre-of-mass energy, W, was 50 < W < 180 GeV. The J/psi mesons were identified through their decay into muon pairs. The polar and azimuthal angles of the mu(+) were measured in the J/psi rest frame and compared to theoretical predictions at leading and next-to-leading order in QCD.
Measurement of J/psi helicity distributions in inelastic photoproduction at HERA
CAPUA, Marcella;Fazio S.;MASTROBERARDINO, Anna;Schioppa M.;TASSI, Enrico;
2009-01-01
Abstract
The J/psi decay angular distributions have been measured in inelastic photoproduction in ep collisions with the ZEUS detector at HERA, using an integrated luminosity of 468 pb(-1). The range in photon-proton centre-of-mass energy, W, was 50 < W < 180 GeV. The J/psi mesons were identified through their decay into muon pairs. The polar and azimuthal angles of the mu(+) were measured in the J/psi rest frame and compared to theoretical predictions at leading and next-to-leading order in QCD.File in questo prodotto:
Non ci sono file associati a questo prodotto.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.