The 7.5-Mev deuteron beam of the $A-48\mathrm{}$ linear accelerator has been used to produce strong sources of the radioactive nuclides ${\mathrm{Co}}^{57}$, ${\mathrm{Ga}}^{67}$, and ${\mathrm{Tc}}^{99}$ by means of the ($d, n$) and ($d, p$) reactions on ${\mathrm{Fe}}^{56}$, ${\mathrm{Zn}}^{66}$, and ${\mathrm{Mo}}^{98}$. ${\mathrm{Co}}^{57}$ and ${\mathrm{Ga}}^{67}$ decay by $K$-capture to excited states at ${\mathrm{Fe}}^{57}$ and ${\mathrm{Zn}}^{67}$. ${\mathrm{Tc}}^{99}$ is made by the reactions ${\mathrm{Mo}}^{98}(d, n){\mathrm{Tc}}^{99}$ and ${\mathrm{Mo}}^{98}(d, p){\mathrm{Mo}}^{99}$ in which ${\mathrm{Mo}}^{99}$ subsequently decays to ${\mathrm{Tc}}^{99}$ with a half-life of 67 hours. Appropriate sources containing these nuclides were exposed in the high-resolution bent quartz crystal spectrograph previously described and photographic spectra were obtained of the strongest nuclear gamma rays emitted by these sources. The plates were calibrated with x-rays and gamma rays of known wavelengths. The energies (in kev) of the various gamma rays measured are: ${\mathrm{Fe}}^{57}$, 122.05±0.05 and 136.40±0.06; ${\mathrm{Zn}}^{67}$, 93.26±0.04 and 184.46±0.27; and ${\mathrm{Tc}}^{99}$, 140.52±0.16. The cascade gamma ray between the two levels in ${\mathrm{Zn}}^{67}$ was also observed and its energy was determined as 91.22±0.04 kev in good agreement with the difference (91.20±0.27 kev) between the values quoted above for this isotope.

• Received 12 November 1957

DOI:https://doi.org/10.1103/PhysRev.109.2036