Leading proton production in e"+p collisions at HERA

Events with a final-state proton carrying a large fraction of the proton beam momentum, x_L > 0.6, and the square of the transverse momentum p_T"2 < 0.5 GeV"2, have been studied in e"+p collisions with the ZEUS detector at HERA. Data with different photon virtualities were used: Q"2 < 0.02 GeV"2, 0.1 < Q"2 < 0.74 GeV"2 and 3 < Q"2 < 254 GeV"2, corresponding to integrated luminosities of 0.9, 1.85 and 3.38 pb"-"1. The cross sections are given as a function of x_L, p_T"2, Q"2 and the Bjorken scaling variable, x. The ratio of the cross section for leading proton production to the inclusive e"+p cross section shows only a mild dependence on Q"2 and on x. In the region 0.6 < x_L < 0.97, the relative yield of protons is only a weak function of x_L. (orig.)Available from TIB Hannover: RA 2999(02-142) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman