Showing papers by "Alberto Santoro published in 1986"

Experimental study of the A dependence of J/ psi photoproduction.

Abstract: We have studied the photoproduction of $\frac{J}{\ensuremath{\psi}}$ mesons on H, Be, Fe, and Pb targets using real photons at a mean energy of 120 GeV. The ${p}_{T}^{2}$ spectra were used to separate the coherent diffractive signals from the incoherent signals. Parametrizing the per-nucleus cross sections in terms of power-law dependences, ${A}^{\ensuremath{\alpha}}$, we find that ${\ensuremath{\alpha}}_{\mathrm{coh}}=1.40\ifmmode\pm\else\textpm\fi{}0.06\ifmmode\pm\else\textpm\fi{}0.04$ for the coherent diffractive signals and ${\ensuremath{\alpha}}_{\mathrm{incoh}}=0.94\ifmmode\pm\else\textpm\fi{}0.02\ifmmode\pm\else\textpm\fi{}0.03$ for the incoherent signals.