RESUMO
Cross sections for elastic Compton scattering from the deuteron were measured over the laboratory angles straight theta(gamma) = 35 degrees -150 degrees. Tagged photons in the laboratory energy range E(gamma) = 84-105 MeV were scattered from liquid deuterium and detected in the large-volume Boston University NaI spectrometer. Using the calculations of Levchuk and L'vov, along with the measured differential cross sections, the isospin-averaged nucleon polarizabilities in the deuteron were estimated. A best-fit value of (alpha;-beta;) = 2.6+/-1.8 was determined, constrained by dispersion sum rules. This is markedly different from the accepted value for the proton of (alpha;-beta;)(p) = 10.0+/-1.5+/-0.9.
RESUMO
Cross sections for quasifree Compton scattering from the deuteron were measured for incident energies of E(gamma) = 236-260 MeV at the laboratory angle straight theta(gamma(')) = -135 degrees. The recoil nucleons were detected in a liquid-scintillator array situated at straight theta(N) = 20 degrees. The measured differential cross sections were used, with the calculations of Levchuk et al., to determine the polarizabilities of the bound nucleons. For the bound proton, the extracted values were consistent with the accepted value for the free proton. Combining our results for the bound neutron with those from Rose et al., we obtain 1-sigma constraints of alpha;(n) = 7.6-14.0 and beta;(n) = 1.2-7.6.