γdecay and splitting of the first analog state inMn53,Co55, andCu59

Abstract

The ..gamma.. decay of the 2p/sub 3/2/ analog state in /sup 5/3Mn, /sup 5/5Co, and /sup 5/9Cu has been studied at 18 MeV by means of the (/sup 3/He,d..gamma..) reaction. The ..gamma.. rays in coincidence with deuterons emitted near 0/sup 0/ were detected by two Ge(Li) detectors located at theta = 90/sup 0/ and 147/sup 0/. Decay schemes, energies, and spins have been established. The 2p/sub 3/2/ analog state in /sup 5/3Mn is located at E/sub x/ = 6971 keV. We confirm that the 2p/sub 3/2/ analog state is split in /sup 5/5Co (E/sub x/ = 4722 and 4747 keV) and in /sup 5/9Cu (E/sub x/ = 3885 and 3904 keV) implying a strong Coulomb mixing with a nearby T/sub less-than/ level. We do not see the large reduction of the M1 analog-antianalog transition previously observed in other nuclei in the f-p shell region. Calculations have been completed in a schematic model. Other levels and particularly 1f/sub 5/2/ and 2p/sub 1/2/ analog states in the same nuclei are also observed and discussed.