Eur. Phys. J. C (2006) 45: 23-33
https://doi.org/10.1140/epjc/s2005-02415-6Measurement of
https://doi.org/10.1140/epjc/s2005-02415-6
Experimental Physics
Measurement of 
and 
at low Q
2 and x * 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 12 ≤ Q
2 ≤ 60 GeV2 and of the Bjorken scaling variable 0.0002 x ≤ 0.005. The fractions of events containing charm and beauty quarks 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. Values for the structure functions and are obtained. This is the first measurement of in this kinematic range. The results are found to be compatible with the predictions of perturbative quantum chromodynamics and with previous measurements of .
© Springer-Verlag, 2006
