Feynman‐x and transverse momentum dependence of D± and D0,D̄0 production in 250 GeV π−‐nucleon interactions

We measure the differential cross section with respect to Feynman‐x (xF) and transverse momentum (PT) for charm meson production using targets of Be, Al, Cu and W. In the range 0.1≤xF≤0.7, dσ/dxF is well fit by the form (1−xF)n with n=3.9±0.2. The difference between n values for D− and D+ is 1.1±0.4. However, we find an asymmetry of 0.18±0.04 favoring the production of D− compared to D+. In the lower PT range, ≤2 GeV, dσ/dP2T is well fit by the form exp(−b×P2T) with b=1.03±0.04 GeV−2, while in the higher PT range, 0.8 to 3.6 GeV, it is well fit by the form exp(−b’×PT) with b’=2.76±0.06 GeV−1. The shape of the differential cross section has no significant dependence on atomic mass of the target material.