Nuclear dependence of neutral-D-meson production by 800 GeV/c protons

The nuclear dependence for 800 GeV/[ital c] proton production of neutron [ital D] mesons has been measured near [ital x][sub [ital F]]=0 in Experiment 789 at Fermilab. [ital D] mesons from beryllium and gold targets were detected with a pair spectrometer and a silicon vertex detector via their decay [ital D][r arrow][ital K][pi]. No nuclear dependence is found, with a measured [alpha]=1.02[plus minus]0.03[plus minus]0.02. The measured differential cross section, [ital d][sigma]/[ital dx][sub [ital F]], for neutral-[ital D]-meson production at [l angle][ital x][sub [ital F]][r angle]=0.031 is 58[plus minus]3[plus minus]7 [mu]b/nucleon. The integrated cross section obtained by extrapolation of the measured cross section to all [ital x][sub [ital F]] is 17.7[plus minus]0.9[plus minus]3.4 [mu]b/nucleon and is consistent with previous measurements.