Multiloop Bubbles for hot QCD

In this article, we present analytical expansion results of two single mass scale four-loop vacuum integrals in d=3-2*ep dimensions. After finding hypergeometric representations with half-integer coefficients, we use algorithms which we implemented in FORM to expand these in terms of nested sums.Comment: 4 pages, to appear in the Proceedings of SEWM08, Amsterdam, the Netherlands, August 26-29, 200

Hypergeometric representation of a four-loop vacuum bubble

In this article, we present a new analytic result for a certain single-mass-scale four-loop vacuum (bubble) integral. We also discuss its systematic \e-expansion in d=4-2\e as well as d=3-2\e dimensions, the coefficients of which are expressible in terms of harmonic sums at infinity.Comment: 5 pages, to appear in the proceedings of the conference "Loops and Legs", Eisenach, 200

Application of the DRA method to the calculation of the four-loop QED-type tadpoles

We apply the DRA method to the calculation of the four-loop `QED-type' tadpoles. For arbitrary space-time dimensionality D the results have the form of multiple convergent sums. We use these results to obtain the epsilon-expansion of the integrals around D=3 and D=4.Comment: References added, some typos corrected. Results unchange