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

We calculate the O(alpha(2)(s)) 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 Q(2) >> m(2). 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 detived previously. The results allow to determine the heavy flavor Wilson coefficients for F,)(x, Q2) to O(alpha(2)(s)) and for FL(x, Q(2)) to O(alpha(3)(s)) for all but the powersuppressed terms alpha(m(2)/Q(2))k >= 1. (C) 2007 Elsevier B.V. All rights reserved.