Anatomy of relativistic pion loop corrections to the electromagnetic nucleon coupling
- North Carolina State University
- JLAB
- Adelaide U.
We present a relativistic formulation of pion loop corrections to the coupling of photons with nucleons on the light-front. Vertex and wave function renormalization constants are computed to lowest order in the pion field, including their nonanalytic behavior in the chiral limit, and studied numerically as a function of the ultraviolet cutoff. Particular care is taken to explicitly verify gauge invariance and Ward-Takahashi identity constraints to all orders in the m_\pi expansion. The results are used to compute the chiral corrections to matrix elements of local operators, related to moments of deep-inelastic structure functions. Finally, comparisons of results for pseudovector and pseudoscalar coupling allows the resolution of a long-standing puzzle in the computation of pion cloud corrections to structure function moments.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- AC05-06OR23177
- OSTI ID:
- 1096220
- Report Number(s):
- JLAB-THY-13-1707; DOE/OR/23177-2503; arXiv:1306.6073
- Journal Information:
- Physical Review D, Vol. 88, Issue 07
- Country of Publication:
- United States
- Language:
- English
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