Measurement of D+ and Λc+ production in deep inelastic scattering at HERA

Charm production in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 120 pb−1. The hadronic decay channels D + → K S 0 π +, Λ c + → pK S 0 and Λ c + → Λπ +, and their charge conjugates, were reconstructed. The presence of a neutral strange hadron in the final state reduces the combinatorial background and extends the measured sensitivity into the low transverse momentum region. The kinematic range is 0 < p T (D +, Λ c +) < 10 GeV, |η(D +, Λ c +)| < 1.6, 1.5 < Q 2 < 1000 GeV2 and 0.02 < y < 0.7. Inclusive and differential cross sections for the production of D + mesons are compared to next-to-leading-order QCD predictions. The fraction of c quarks hadronising into Λ c + baryons is extracted.