Two-loop corrections to the electromagnetic vertex for energies close to threshold
نویسندگان
چکیده
منابع مشابه
Two - Loop Corrections to the Electromagnetic Vertex for Energies close to Threshold
Two-loop contributions to the electromagnetic form factors are calculated in the kinematic regime close to the fermion-antifermion threshold. The results are presented in an expansion in the velocity β of the fermions in the c.m. frame up to next-to-next-to leading order in β. The existence of a new Coulomb singularity logarithmic in β, which is closely related to the O(α 2 ln α) corrections kn...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 1997
ISSN: 0556-2821,1089-4918
DOI: 10.1103/physrevd.56.7276