Proton GE/GM from beam-target asymmetry
Abstract
The ratio of the proton's electric to magnetic form factor, GE/GM, can be extracted in elastic electron-proton scattering by measuring cross sections, beam-target asymmetry, or recoil polarization. Separate determinations of GE/GM by cross sections and recoil polarization observables disagree for Q2>1 (GeV/c)2. Measurement by a third technique might uncover an unknown systematic error in either of the previous measurements. The beam-target asymmetry has been measured for elastic electron-proton scattering at Q2 = 1.51 (GeV/c)2 for target spin orientation aligned perpendicular to the beam momentum direction. This is the largest Q2 at which GE/GM has been determined by a beam-target asymmetry experiment. The result, μGE/GM=0.884±0.027±0.029, is compared to previous world data.
- Publication:
-
Physical Review C
- Pub Date:
- September 2006
- DOI:
- arXiv:
- arXiv:nucl-ex/0606015
- Bibcode:
- 2006PhRvC..74c5201J
- Keywords:
-
- 25.30.Bf;
- 13.40.Gp;
- Elastic electron scattering;
- Electromagnetic form factors;
- Nuclear Experiment
- E-Print:
- 8 pages, 6 figures, Updated to be version published in Physical Review C