Two-body Photodisintegration of ³He

Abstract: In a series of experiments using the tagged photon facility at MAX-lab located in Lund, Sweden, the two-body photodisintegration of ³He has been investigated in the photon energy range 14--32 MeV. Differential cross sections of the reaction ³He(g,d) have been measured by detecting deuterons and protons in silicon surface barrier detectors. The detectors were configured into four particle identification telescopes located at an angel 90 degrees with respect to the incident photon beam. Utilizing the high energy resolution of the tagging spectrometer and of the silicon detectors, and as a consequence of the over-determined kinematical system, it was possible to discriminate the two-body break-up channel from the three-body break-up channel by the detection of the proton only. The differential cross sections have been compared to two recent Faddeev calculations. The first, based on the AV18 NN potential and the explicit inclusion of the three-nucleon force Urbana IX; the second, based on the CD-Bonn NN potential and the coupled-channel extension CD-Bonn + Delta. The inclusion of the Delta-isobar results in an effective three-nucleon force. Good agreement between the calculations and the measured cross sections is found.