Measurement of charm fragmentation fractions in photoproduction at HERA

Understand

The production of D^0, D^*+, D^+, D_s+ and Lambda_c^+ charm hadrons and their antiparticles in ep scattering at HERA has been studied with the ZEUS detector, using a total integrated luminosity of 372 pb^-1.

• The fractions of charm quarks hadronising into a particular charm hadron were derived.
• In addition, the ratio of neutral to charged D-meson production rates, the fraction of charged D mesons produced in a vector state, and the stangeness-suppression factor have been determined.
• The measurements have been performed in the photoproduction regime.