The H(n, y)'H reaction has been studied with polarized and unpolarized neutrons of energies ranging from 9 to 14 MeV. Angular distributions of cross section were measured at E"(lab) =9.0, 10.8, and 14.0 MeV, o(90') was measured at 6.85 MeV, and an analyzing-power angular distribution was measured at 9.0 MeV. The results for cr (8) agree with the existing 'H(y, n) H data after detailed balancing. The resulting He(y, p)/ H(y, n) ratio for 90' cross sections is 1.1+0.15 down to E"=10. 8 MeV. The T-matrix analysis of the data indicates -3% for the E2 contribution to the capture cross sectioncomparable to that found earlier for H(p, y)'He and in contrast to the predictions [o"(E2)/n~(E2) = 1/25] of a two-body direct-capture calculation.

The analyzing power in proton-proton scattering has been measured at bombarding energies of 5.05 and 9.85 MeV to an accuracy of ± 5x 10" 5 . The measurements were combined with existing cross-section data to obtain model-independent S-and P-wave phase shifts at these energies. In addition, the first experimental determination of theP-wave scattering lengths and effective ranges is reported. These are compared to model values and their use in obtaining improved S-wave parameters is suggested.

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