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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.

The cross section for the reaction 1 H͑␥, 0 ͒ has been measured using tagged photons in the threshold region ͑144.7-169.3 MeV͒. The total cross section, augmented by angular distribution information, is used to deduce the S-wave multipole E 0ϩ . Extrapolation to threshold yields E 0ϩ ϭ(Ϫ1.32Ϯ0.05Ϯ0.06)ϫ10 Ϫ3 /m , in disagreement with earlier estimates. Suppression of E 0ϩ near the ϩ threshold is confirmed, in approximate agreement with recent calculations.PACS number͑s͒: 25.20.Lj, 13.60.Le

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