Two-loop massive operator matrix elements and unpolarized heavy flavor production at asymptotic values Q2≫m2

We calculate the O(αs2) massive operator matrix elements for the twist-2 operators, which contribute to the heavy flavor Wilson coefficients in unpolarized deeply inelastic scattering in the region Q2≫m2. The calculation has been performed using light-cone expansion techniques. We confirm an earlier result obtained in [M. Buza, Y. Matiounine, J. Smith, R. Migneron, W.L. van Neerven, Nucl. Phys. B 472 (1996) 611, hep-ph/9601302]. The calculation is carried out without using the integration-by-parts method and in Mellin space using harmonic sums, which lead to a significant compactification of the analytic results derived previously. The results allow to determine the heavy flavor Wilson coefficients for F2(x,Q2) to O(αs2) and for FL(x,Q2) to O(αs3) for all but the power suppressed terms ∝(m2/Q2)k,k⩾1.