We measure the differential cross sections with respect to Feynman $x$ ( $x_F$) and transverse momentum ( $p_T$) for $\pi$, $K$, and $p$-induced charm meson production using fully reconstructed $D^{+}$, $D^0$, and $D_s$ decays. The shapes of these cross sections are compared to the theoretical predictions for charm quark production of next-to-leading order perturbative QCD using modern parametrizations of the pion and nucleon parton distributions. We observe the differences expected in production induced by projectiles with different gluon distributions, harder distributions being indicated for mesons than for protons.

• Received 26 March 1996

DOI:https://doi.org/10.1103/PhysRevLett.77.2392