Small-threshold Behaviour of Two-loop Self-energy Diagrams: Some Special Cases * †
نویسنده
چکیده
An algorithm to construct analytic approximations to two-loop diagrams describing their behaviour at small non-zero thresholds is discussed. For some special cases (involving two different-scale mass parameters), several terms of the expansion are obtained. ∗ Presented at QCD and QED in Higher Order, 1996 Zeuthen Workshop on Elementary Particle Theory, Rheinsberg, April 21–26, 1996, to appear in Nucl. Phys. B (Proc. Suppl.). † This research was supported by the EU under contract number INTAS-93-0744.
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تاریخ انتشار 1996