GEp/GMp Ratio by Polarization Transfer in epep

Phys. Rev. Lett. 84, 1398 – Published 14 February 2000
M. K. Jones et al. (The Jefferson Lab Hall A Collaboration)


The ratio of the proton's elastic electromagnetic form factors, GEp/GMp, was obtained by measuring Pt and P, the transverse and the longitudinal recoil proton polarization, respectively. For elastic epep, GEp/GMp is proportional to Pt/P. Simultaneous measurement of Pt and P in a polarimeter provides good control of the systematic uncertainty. The results for the ratio GEp/GMp show a systematic decrease as Q2 increases from 0.5 to 3.5 GeV2, indicating for the first time a definite difference in the spatial distribution of charge and magnetization currents in the proton.


  • Received 4 October 1999
  • Published in the issue dated 14 February 2000

© 2000 The American Physical Society

Authors & Affiliations

References (Subscription Required)

Authorization Required




Log In



Article Lookup
Paste a citation or DOI

Enter a citation
  1. Enter a citation to look up or terms to search.

    Ex: "PRL 112 068103", "Phys. Rev. Lett. 112, 068103", "10.1103/PhysRevLett.112.068103"