Speaker
Karin Daum
(Wuppertal University)
Description
Inclusive production of D* mesons in deep inelastic scattering at HERA is
studied. The data were taken with the H1 detector in the years 2004 to 2007
and correspond to an integrated luminosity of ~350 pb^-1. D* mesons are
reconstructed in their decays D* -> D0 + pi_slow -> K + pi + pi_slow.
The visible range for the measurements covers the pseudorapidity
interval |eta(D*)| <1.5, transverse momenta pT(D*)>1.5 GeV, and
inelasticity in the scattering process 0.02 < y < 0.7.
The cross sections are measured for low photon virtualities, 5<Q^2<100 GeV,
and, for the first time with the H1 experiment, for high photon
virtualities Q^2 > 100 GeV^2. Single and double differential
cross sections are measured and compared to predictions from the
next-to-leading order calculation HVQDIS and the leading order Monte
Carlo programs RAPGAP and CASCADE.
The charm contribution to the proton structure, F2(ccbar), is
determined for the kinematic region 7 GeV^2 < Q^2 < 440 GeV^2 and
10^-4 < x_bj < 3 * 10^-2 by extrapolating the visible D* meson cross
section measured by the H1 collaboration to the full phase space using
the NLO QCD calculation HVQDIS, based on DGLAP evolution, and CASCADE,
a LO Monte-Carlo program including parton showers based on
CCFM evolution.
The production of D+/- and D0 mesons has been measured with the ZEUS detector
at HERA using an integrated luminosity of 133.6 pb^-1. The measurements cover
the kinematic range 5 < Q2 < 1000 GeV2, 0.02 < y < 0.7, 1.5 < pT(D) < 15 GeV and
|eta(D)|<1.6. Combinatorial background to the D meson signals is reduced
by using the ZEUS microvertex detector to reconstruct displaced secondary
vertices. Production cross sections are compared with the predictions of
next-to-leading-order QCD which is found to describe the data well.
Measurements are extrapolated to the full kinematic phase space in order
to obtain the open-charm contribution, F2(ccbar), to the proton structure
function, F2.
Primary author
Karin Daum
(Wuppertal University)
Co-author
Katja Krueger
(Heidelberg University)
