Gamma radiations with energies less than 3 Mev have been observed with an intermediate-image lens spectrometer when targets of aluminum and fluorine were bombarded by protons. Gamma-ray spectra from Al+$p$ were obtained for proton energies of 2.4, 3.0, 4.0, and 4.4 Mev. Gamma radiation with quantum energies of 0.845, 1.014, 1.722, 2.216, and 2.992 Mev were observed and are attributed to excited states of ${\mathrm{Al}}^{27}$. Gamma radiations of 1.369 Mev from ${\mathrm{Mg}}^{24}$ and 2.741 Mev, probably from both ${\mathrm{Al}}^{27}$ and ${\mathrm{Mg}}^{24}$, were also observed. Internal conversion electrons from the excited states of ${\mathrm{Al}}^{27}$ were observed; the conversion coefficients indicate that the 0.845-Mev radiation is $E2\mathrm{}$ and that the 1.014-Mev radiation is $M1\mathrm{}$. Gamma radiation from ${\mathrm{F}}^{19}$+$p$ was observed with quantum energies of 1.236, 1.358, and 1.46 Mev. The relative intensities of the $\gamma$ rays were observed for proton energies of 3.22, 3.65, and 4.27 Mev.

• Received 5 June 1958

DOI:https://doi.org/10.1103/PhysRev.112.239