A STUDY OF RA-223 POPULATED BY ALPHA-DECAY

The low spin states of Ra-223 have been populated via cr-decay from Th -227 which was itself produced following beta(-) decay of an Ac-227 so urce. alpha-gamma and alpha - e(K,L,M) angular correlation measurement s have been analysed using the correct ground state spins of Th-227(= 1/2(+)) and Ra-223(= 3/2(+)) for the first time. The analysis has allo wed unique J(pi) values to be assigned to almost all levels below 400 keV excitation in Ra-223. Values of (g(K) - g(R))/Q(0) have been deduc ed for several members of the K = 3/2(+/-) bands (for the first time i n an odd N nucleus in this mass region) allowing estimates of g(K) and g(R) to be extracted. The values of g(K) and g(R) are not significant ly different for the positive and negative parity band members and ten d to support other strong evidence that stable octupole deformation ex ists in Ra-223 at low excitation energies.