STATES IN O-20 BELOW MEV EXCITATION VIA THE O-18(T,P) O-20 REACTION

Angular distributions have been measured for the O18(t,p) O20 reaction at a bombarding energy of 15.0 MeV. Nine excited states below 6.02 MeV were observed. Comparison with microscopic two-particle distorted-wave Born approximation calculations yielded the following new J assignments (Ex in MeV, J): 5.382, 0+; 5.603, 2+; 6.02, 4+. Tentative assignments of (1-, 2+, 3-) and (1-, 2+) were made to levels at 5.00 and 5.22 MeV, respectively. Spins of 2+, 4+, 2+, and 0+ to the levels at 1.674, 3.568, 4.065, and 4.446 MeV were confirmed. The experimental spectrum of states below 6 MeV is compared with the results of an (sd)4 shell-model calculation using the Preedom-Wildenthal interaction matrix elements. Identification of possible core-excited states in O20 is discussed. NUCLEAR REACTIONS C12(t, p), O16,18(t, p), E=15.0 MeV; measured (Ep,). O20 deduced levels, J. Enriched target, DWBA analysis, shell model calculation. © 1979 The American Physical Society.