Differential Cross Section for Coherent Photon Scattering fromHe4at 180 MeV

Abstract
We report the measurement of the differential scattering cross section for coherent photon scattering (nuclear Compton scattering) from He4 at an average energy of 180 MeV. This represents the first direct observation of the coherent process on a complex nucleus above the pion threshold. The results are compared with the prediction of a calculation utilizing the isobar-hole formalism.