Two-Body Hard Photodisintegration of 3He to p-d


  Ishay Pomerantz  ,  Eli Piasetzky  
Tel Aviv University

I will present the first results for photodisintegration of 3He into a p-d system at photon energies Egamma = 0.4 -- 1.4 GeV. In this range the cross falls by two orders of magnitude and is observed to scale with: d\sigma/dt ~ s-17. This is the first time scaling has been observed on a nuclear system heavier than the deuteron and the highest scaling power ever observed in an exclusive reaction. The magnitude of the pd cross section at Egamma = 0.7 GeV is about 3 times smaller than for breakup of a $pp$ pair in 3He, with a neutron spectator, and about two orders of magnitude smaller than deuteron photodisintegration at the same incident photon energy.