Pion photoproduction in a nonrelativistic theory
نویسنده
چکیده
The pion and nucleon mass differences generate a very pronounced cusp in the photoproduction reaction of a single pion on the nucleon. A nonrelativistic effective field theory to describe this reaction is constructed. The approach is rigorous in the sense that it is an effective field theory with a consistent power counting scheme. Expressions for the Sand P -wave multipole amplitudes for all four reaction channels at two loops are given.
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تاریخ انتشار 2009