Measurement of $F_2^{c\overline{c}}$ and $F_2^{b\overline{b}}$ at high $Q^2$ using the H1 vertex detector at HERA

Measurements are presented of inclusive charm and beauty cross sections in e$^+$p collisions at HERA for values of photon virtuality Q$^2$ > 150 GeV$^2$ and of inelasticity 0.1 < y < 0.7. The charm and beauty fractions are 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. The data are divided into four regions in Q$^2$ and Bjorken x, and values for the structure functions $F_2^{c\overline{c}}$ and $F_2^{b\overline{b}}$ are obtained. The results are found to be compatible with the predictions of perturbative quantum chromodynamics.