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The quality and intensity of gamma rays at the High Intensity gamma-ray Source are shown to make nuclear resonance fluorescence studies possible at a new level of precision and efficiency. First experiments have been carried out using an intense (10(7) gamma/s) beam of 100% linearly polarized, nearly monoenergetic, gamma rays on the semimagic nucleus (138)Ba. Negative parity quantum numbers have been assigned to 18 dipole excitations of (138)Ba between 5.5 MeV and 6.5 MeV from azimuthal gamma-intensity asymmetries.

The 2H(p, y) He reaction has been studied in the energy region E =80 -0 keV (E, =53,3 -0 keV), where the quantities measured were a(H, E) and A (//, E') Our res.ult for the total H(p, y) He 5 factor at E Oi=s S(0) =0.121~0.012 eV b (including systematic error), which is 52% lower than the presently accepted value. Some astrophysical aspects of this result are discussed. We have also extracted the El and M 1 S(E) components using our detailed angular distribution data. These data will provide sensitive tests for three-body calculations which include Coulomb and meson exchange current effects. PACS number(s): 25.40.Lw, 24.70.+s, 95.30.CqThe motivation to experimentally study the H(p, y) He reaction at low energies is twofold: first of all, to further test and refine the results of theoretical three-body calculations and second, to study the aspects of the H(p, y) He reaction which are of interest in astrophysics. The basic physics impetus for the current H(p, y) He work was provided by a recently published exact three-body calculation [1] for the tored to gauge changes in the purity of the D20 ice target (no problems were encountered). Figure 1(b) shows a blow up of the full energy peak (with the anticoincidence condition ap-0556-2813/95/52(4)/1732(4)/$06. 00

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