Production of$\bar D^0$ andD ⁻ mesons in neutron-carbon interactions at 40–70 GeV

Abstract

The production of$\bar D$ mesons in neutroncarbon interactions at 40–70 GeV/c has been investigated. The$\bar D$ mesons were detected via the hadronic decay modes$\bar D^0 \to K^{* + } (892)\pi ^ -$ andD ⁻→K ^*+(892)π⁻π⁻. In the kinematical regionx _F >0.5 andp _T <1 GeV/c the following inclusive cross sections were measured:$\sigma _{\bar D^0 } = (28 \pm 14)\mu b$ and$\sigma _{D^ - } = (28 \pm 13)\mu b$ per carbon nucleus. The invariant longitudinal momentum spectra can be described by (1−x)^N with$N_{\bar D^0 } = 1.1 \pm 0.5 \pm 0.4$ and$N_{D^ - } = 0.8 \pm 0.4 \pm 0.4$ The transverse momentum spectra were parametrized by exp (−Bp ² _T ) with$B_{\bar D^0 } = (1.2_{ - 0.9}^{ + 1.1} )({{GeV} \mathord{\left/ {\vphantom {{GeV} c}} \right. \kern-\nulldelimiterspace} c})^{ - 2}$ and$B_{D^ - } = (1.8_{ - 1.0}^{ + 1.3} )({{GeV} \mathord{\left/ {\vphantom {{GeV} c}} \right. \kern-\nulldelimiterspace} c})^{ - 2}$.