H1 Collaboration

Abstract

Abstract Measurements are presented of inclusive charm and beauty cross sections in e+p collisionsat HERA for values of photon virtuality 12 < = Q2 < = 60 GeV2 and of the Bjorken scalingvariable 0.0002 < = x < = 0.005. The fractions of events containing charm and beauty quarksare determined using a method based on the impact parameter, in the transverse plane, of tracks to the primary vertex, as measured by the H1 vertex detector. Values for the structurefunctions F c_c2 and F b_b2 are obtained. This is the first measurement of F b_b2 in this kinematicrange. The results are found to be compatible with the predictions of perturbative quantum chromodynamics and with previous measurements of F c_c2