RadionuclideK37

The radionuclide ${\mathrm{K}}^{37}$ has been produced by a ($p, \alpha$) reaction on ${\mathrm{Ca}}^{40}$, using 12.8-Mev protons accelerated in the UCLA 20-Mev synchrocyclotron. The half-life of this activity was found to be 1.2±0.12 seconds. With a double-channel magnetic spectrometer the end point of the $\beta$ spectrum was determined as 5.10±0.07 Mev. The $\mathrm{ft}$ value determined as 4150±500 seconds is within the expected range of the shell-model predictions. The Coulomb energy difference between ${\mathrm{K}}^{37}$ and ${\mathrm{A}}^{37}$ deduced from the end point agrees with Peaslee's analysis of the light nuclei. The pairing effect in Coulomb energies discussed by Carlson and Talmi is more clearly exhibited with the addition of the new data.