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VOLUME 15, NUMBER 25 PHYSICAL REVIE%'LETTERS 20 DEcEMBER 1965 in 0" have positive parity. Recent angulardistribution measurements for the reaction N~(P, y,) O~~ done by Tanner, Thomas, and Earle at Oxford indicate that dipole processes dominate in this energy region so that a combination of experimental results leadsto J"= 1+ for the 21. 0-MeV level.(2) Upon further increase in excitation en-ergy the neutron spectrum returns to essen-tially ground-state-only values, coincident with the onset of the broad 22.3-MeV state in 0". At 21. 8 MeV we obtain a value of 0+ 3% for branching to the positive-parity state (s).(3) Beginning at 21. 8 MeV another sharp change in the neutronspectrum occurs, coin-ciding with the threshold for leaving 0'5 in its 6. 16-MeV (2) excited state.(4) Marked changes in the spectrum toward higher average neutron energies occur near 23 and 24 MeV. As can be seen in Fig. 3 (b …