Gamma Rays from the Proton Bombardment of 24Mg, 25Mg and 26Mg

The gamma-rays following the inelastic scattering of protons by 24 Mg, 25 Mg and 26 Mg were investigated at proton energies up to 5.7 MeV. The energy spectra of the gamma-rays at several proton energies have been obtained for each isotopes. 2 + was assigned to the second, third and fourth excited level of 26 Mg considering the gamma-ray branching ratios for those levels. The yields of gamma-rays from the first excited levels were found to have peaks at proton energies of 4.0, 4.6 and 5.05 MeV for 24 Mg( p , p 'γ) reaction, 4.9 and 5.4 MeV for 25 Mg( p , p 'γ) reaction respectively. These resonances correspond to the levels at 6.1, 6.7 and 7.14 MeV for 25 Al, and 13.0 and 13.5 MeV for 27 Al. To determine the spins for those levels, angular distributions were measured at resonance energies. Spin values of 3/2 and 5/2 are probable for 7.14 MeV level in 25 Al and 13.0 MeV level in 27 Al respectively. For the 13.5 MeV level in 27 Al, the spin of 3/2 is also probable, but 5/2 can not be excluded because of the ...