Is the "Heavy Quark Damping Rate Puzzle" in Hot QCD Really a Puzzle?

A. Niégawa
1994 Physical Review Letters  
Within the framework of perturbative resummation scheme of Pisarski and Braaten, the decay- or damping-rate of a moving heavy quark (muon) to leading order in weak coupling in hot QCD (QED) is examined. Although, as is well known, the conventionally-defined damping rate diverges logarithmically at the infrared limit, shown is that no such divergence appears in the physically measurable decay rate. The cancellation occurs between the contribution from the \lq\lq real" decay diagram and the
more » ... bution from the diagrams with \lq\lq thermal radiative correction".
doi:10.1103/physrevlett.73.2023 pmid:10056952 fatcat:e3ws2hlwdza4xlcqihlj77o57a