Renormalization of HQET at Three Loops

Three-loop propagator diagrams in HQET can be reduced, using integration by parts, to 8 basis integrals: 5 trivial ones, two expressible via 3F2, and one only known up to \epsilon^0. Calculation of the heavy-quark propagator in HQET is considerably simplified by the non-abelian exponentiation theorem.Comment: Talk at the QCD workshop, Martina Franca, 17-20 June, to be published in the Proceedings; LaTeX2e, aipproc document class (included), 7 pages, 7 eps figures (included