Double Bubble Corrections to Heavy Quark Production

Abstract

Second order ${\cal O}(α_s^2)$ corrections to the heavy quark production cross-section due to massless quarks and coloured scalars are calculated for all energies above threshold. Based on the method introduced in this letter also the gauge non-invariant second order corrections due to the pure gluonic selfenergy insertion and a certain class of ${\cal{O}}(α_s^3)$ and ${\cal{O}}(α_s^4)$ corrections are determined. For the special choice of the gauge parameter, $ξ=4$, the leading threshold and high energy behaviour of the pure second order gluonic corrections to the cross-section are governed by the gluonic self energy insertion.

9 pages, latex, 17 figures, the complete postscript file of this preprint, including figures, is available via anonymous ftp at ftp://www-ttp.physik.uni-karlsruhe.de/ttp96-04/ttp96-04.ps (129.13.102.139) or via www at http://www-ttp.physik.uni-karlsruhe.de/cgi-bin/preprints/