Measurement of D^(*+-) Meson Production and F_2^c in Deep-Inelastic Scattering at HERA

TL;DR

This paper measures D* meson production in deep-inelastic scattering at HERA, compares results with QCD predictions, and extracts the charm contribution to the proton structure function, revealing its increase with Q^2.

Contribution

It provides the first detailed measurement of D* meson production and the charm structure function F_2^c in a broad kinematic range at HERA, testing perturbative QCD models.

Findings

D* production cross section measured at 8.50 nb with uncertainties.

F_2^c increases from 10% to over 25% as Q^2 rises.

Data agrees with perturbative QCD calculations within uncertainties.

Abstract

The inclusive production of D^{*+-}(2010) mesons in deep-inelastic scattering is studied with the H1 detector at HERA. In the kinematic region 1<Q^2<100 GeV^2 and 0.05<y<0.7 an e^+p cross section for inclusive D^(*+-) meson production of 8.50+- 0.42 (stat.)^(+1.21)_(-1.00) (syst.) nb is measured in the visible range p_(tD^*)>1.5 GeV and |\eta_(D^*)|<1.5. Single and double differential inclusive D^(*+-) meson cross sections are compared to perturbative QCD calculations in two different evolution schemes. The charm contribution to the proton structure, F_2^c(x,Q^2), is determined by extrapolating the visible charm cross section to the full phase space. This contribution is found to rise from about 10% at Q^2 = 1.5 GeV^2 to more than 25% at Q^2 = 60 GeV^2 corresponding to x values ranging from 5*10^(-5) to 3*10^(-3)$.