English

Chiral symmetry and the Delta-Nucleon transition form factors

High Energy Physics - Phenomenology 2009-10-31 v3

Abstract

The three complex form factors entering the ΔNγ\Delta\to N\gamma^\ast vertex are calculated to O(ϵ3){\cal O}(\epsilon^3) in the framework of a chiral effective theory with explicit \Delta(1232) degrees of freedom included. It is shown that the low q^2 behavior of the form factors is governed by πN\pi N, πΔ\pi\Delta loop effects. Predictions are given for the q^2-dependence of the three transition-multipoles M1(q2),E2(q2),C2(q2)M1(q^2), E2(q^2), C2(q^2). Furthermore, the role of presently unknown low energy constants that affect the values of the multipole ratios EMR(q^2) and CMR(q^2) is elucidated.

Keywords

Cite

@article{arxiv.hep-ph/9810426,
  title  = {Chiral symmetry and the Delta-Nucleon transition form factors},
  author = {G. C. Gellas and T. R. Hemmert and C. N. Ktorides and G. I. Poulis},
  journal= {arXiv preprint arXiv:hep-ph/9810426},
  year   = {2009}
}

Comments

37 pages, 12 figures