First measurement of the helicity-dependent <![ IGNORE [ γ<![ IGNORE [ p|-->pη differential cross-section
Abstract
The helicity dependence of the <![ IGNORE [ γ<![ IGNORE [ p|-->pη reaction has been measured for the first time at a center-of-mass angle θ*η = 70° in the photon energy range from 780 MeV to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4π-detector system, a circularly polarized, tagged photon beam, and a longitudinally polarized frozen-spin target. The helicity 3/2 cross-section is found to be small and the results for helicity 1/2 agree with predictions from the MAID analysis.
- Publication:
-
European Physical Journal A
- Pub Date:
- 2003
- Bibcode:
- 2003EPJA...17..241G