J. Breitweg et al., Measurement of D*(+/-) production and the charm contribution to F-2 in deep inelastic scattering at HERA, EUR PHY J C, 12(1), 2000, pp. 35-52
The production of D*(+/-)(2010) mesons in deep inelastic scattering has bee
n measured in the ZEUS detector at HERA using an integrated luminosity of 3
7 pb(-1). The decay channels D*(+) --> D(0)pi(+) (+ c.c.), with D-0 --> K(-
)pi(+) or D-0 --> K(-)pi(-)pi(+)pi(+), have been used to identify the D mes
ons. The e(+)p cross section for inclusive D*(+/-) production with 1 < Q(2)
< 600 GeV2 and 0.02 < y < 0.7 is 8.31+/-0.31(stat.)(+0.30)(-0.50) (syst.)
nb in the kinematic region 1.5 < pT(D*(+/-)) < 15GeV and \eta(D*(+/-))\ < 1
.5. Differential cross sections are consistent with a next-to-leading-order
perturbative-QCD calculation when using charm-fragmentation models which t
ake into account the interaction of the charm quark with the proton remnant
. The observed cross section is extrapolated to the full kinematic region i
n pr(D*(+/-)) and eta(D*(+/-)) in order to determine the charm contribution
, F-2(c (c) over bar)(x,Q(2)), to the proton structllre function. The ratio
F-2(c (c) over bar)/F-2 rises from similar or equal to 10% at Q(2) similar
or equal to 1.8 GeV2 to similar or equal to 30% at Q(2) similar or equal t
o 130 GeV2 for x values in the rarlge 10(-4) to 10(-3).