ISSN:
1434-6052
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract. The production of $D^{\ast \pm}$ (2010) mesons in deep inelastic scattering has been measured in the ZEUS detector at HERA using an integrated luminosity of 37 pb $^{-1}$ . The decay channels $D^{\ast +}\rightarrow D^0 \pi^+ $ (+ c.c.), with $D^0 \rightarrow K^- \pi^+$ or $D^0 \rightarrow K^- \pi^- \pi^+ \pi^+$ , have been used to identify the D mesons. The $e^+p$ cross section for inclusive $D^{\ast \pm}$ production with $1 〈 Q^2 〈 600\,$ GeV $^2$ and $0.02〈 y 〈 0.7$ is $8.31 \pm 0.31 \mbox{(stat.)}^{+0.30}_{-0.50}\mbox{(syst.)}$ nb in the kinematic region $1.5 〈 p_T(D^{\ast \pm}) 〈 15$ GeV and $|\eta(D^{\ast \pm})| 〈 1.5$ . Differential cross sections are consistent with a next-to-leading-order perturbative-QCD calculation when using charm-fragmentation models which take into account the interaction of the charm quark with the proton remnant. The observed cross section is extrapolated to the full kinematic region in $p_T(D^{\ast \pm})$ and $\eta(D^{\ast \pm})$ in order to determine the charm contribution, $F_{2}^{c\bar c}(x,Q^2)$ , to the proton structure function. The ratio $F_{2}^{c\bar c}/F_{2}$ rises from $\simeq$ 10% at $Q^2 \simeq$ 1.8 GeV $^2$ to $\simeq$ 30% at $Q^2 \simeq $ 130 GeV $^2$ for x values in the range $10^{-4}$ to $10^{-3}$ .
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s100529900244
