Fine structure of analogue states in 55Co, 57Co and 59Co

Excited levels and isobaric analogue states in55Co investigated with the54Fe(p, ?)55Co reaction

“…The schematic level schemes for analogue states in the two nuclei 5SFe and 55Co are shown in Figure 5 together with the Coulomb displacement energies between the parent and analogue states. These values are in good agreement with Lindstrom et al [23], but low compared to the 9078 + 59 keV value given by Ahmed et al [42].…”

“…This ratio may be compared to the ratio of the steps in the thick target yield for high energy gamma rays. In the paper by Maripuu [7] this is found to be 1.4. cation with a (/),7) resonance at Ep=2216keV, a resonance which according to the structure of the yield curve is the same as the Ep = 2206 keV, J = 3/2, resonance in our measurements and which has not been observed by Lindstrom et al [23]. The angular distribution measurement of the primary gamma ray to the 2165keV level at Ep=2243 keV gives no unambiguous spin determination, but 3/2 is less probable than 7/2.…”

“…The resonance energies are listed in Table 1 together with the results of recent (p, 7) and (p, p') experiments [6,7,23]. In general the agreement is good.…”

“…The 3/2 value is less probable because the Z 2 value is above the 1 ~ probability limit. Lindstrom et al [23] have however reported a strong resonance at Ep= 2243.1 keV in a (p, p') experiment with spin and parity 3/2-. If the 7/2 assumption is correct we must have two close lying resonances with spins 3/2 and 7/2 similar to the doublet at Ep = 1802 keV.…”

“…The distribution to the 7/2-ground state excludes 1/2 and makes 3/2 highly improbable because of large octupole mixing. [6] c) [7] d) [23] …”