Session D7 - Hadron Physics.
ORAL session, Saturday afternoon, May 01
Governor's Square 16, Adam's Mark Hotel
We have measured the Q ^2 -dependence (from 1 to 6 GeV ^2 ) of final-state interactions (FSIs) in quasi-elastic electron scattering on deuterium using the CEBAF Large Acceptance Spectrometer (CLAS). The significant reduction of FSIs with Q ^2 compared to predictions based on the eikonal approach provides evidence for color transparency (CT). The large acceptance of CLAS allows us to detect high-momentum protons in the direction of the virtual photon (from which neutron recoil momenta can be deduced) or low-momentum (250-800 MeV/c) recoil protons at large angles. FSIs enhance the recoil momentum perpendicular to the virtual photon as compared to the usual Fermi motion. The experimental ratio of the number of events with recoil momentum near 450 MeV/c compared to near 200 MeV/c decreases with Q^2 as predicted in models of CT. Preliminary results will be shown.