English

The size of the proton - closing in on the radius puzzle

High Energy Physics - Phenomenology 2012-11-07 v2 Nuclear Experiment Nuclear Theory

Abstract

We analyze the recent electron-proton scattering data from Mainz using a dispersive framework that respects the constraints from analyticity and unitarity on the nucleon structure. We also perform a continued fraction analysis of these data. We find a small electric proton charge radius, r_E^p = 0.84_{-0.01}^{+0.01} fm, consistent with the recent determination from muonic hydrogen measurements and earlier dispersive analyses. We also extract the proton magnetic radius, r_M^p = 0.86_{-0.03}^{+0.02} fm, consistent with earlier determinations based on dispersion relations.

Keywords

Cite

@article{arxiv.1205.6628,
  title  = {The size of the proton - closing in on the radius puzzle},
  author = {I. T. Lorenz and H. -W. Hammer and Ulf-G. Meißner},
  journal= {arXiv preprint arXiv:1205.6628},
  year   = {2012}
}

Comments

4 pages, 2 figures, fit improved, small modifications, section on continued fractions modified, conclusions on the proton charge radius unchanged, version accepted for publication in European Physical Journal A