Automatic Computation Of Three-Loop Two-Point Functions In Large Momentum Expansion

Abstract

We discuss the calculation of two-point three-loop functions with an arbitrary number of massive propagators and one large external momentum. The relevant subdiagrams are generated automatically. The resulting massless two-point integrals and massive tadpoles are transformed on-line to FORM-expressions ready to be used by existing FORM packages which calculate them analytically. As an example we compute the quartic mass corrections to the photon polarization function.

Comments: Coefficients of example in Sect. 3 corrected. Latex, 5 pages, 1 ps-figure. Extended version of the contribution to the proceedings of the AIHENP96 workshop in Lausanne, September 1996. The complete paper, including figures, is also available via anonymous ftp at ftp://ttpux2.physik.uni-karlsruhe.de/ , or via www at http://www-ttp.physik.uni-karlsruhe.de/cgi-bin/preprints/