Compton Scattering from the Deuteron at Low Energies

Abstract: A series of three Compton scattering experiments on deuterium have been performed at the high-resolution tagged-photon facility MAX-lab located in Lund, Sweden. The 50 < Eg < 70 MeV tagged photons were scattered from a liquid deuterium target and detected simultaneously in three (10"x10") NaI detectors. The average laboratory angles investigated were 45, 125 and 135 deg. The influence of the inelastic contribution was minimized by implementing a narrow elastic fit-region in the missing energy spectra. Absolute cross sections were extracted for average photon energies of 55 and 66 MeV at each angle and for each experiment. The extracted cross sections are in good agreement with those measured at Illinois by Lucas et al. The difference between the electric and magnetic isospin-averaged polarizabilities of the nucleon inside the deuteron, was varied within the calculations of Levchuk and L'vov to best reproduce the data, holding the sum fixed at 14.6 (10-4 fm3). The result implies that the electric polarizability of the neutron is the same as that of the proton within the experimental uncertainties. The result also indicates that the magnetic polarizability of the neutron is larger than that of the proton.