β+decays ofCa37: Implications for the efficiency of theCl37solar ν detector

We studied $^{37}\mathrm{Ca}$ ${\mathrm{\ensuremath{\beta}}}^{+}$ decays using a mass separated $^{37}\mathrm{Ca}$ beam and a proton telescope with 16-keV resolution. Delayed p's were detected in coincidence with \ensuremath{\gamma}'s to identify p decays of $^{37}\mathrm{K}$ daughter levels to excited states of $^{36}\mathrm{Ar}$. We observed 43 previously undetected proton groups, yielding an integrated B(GT) twice as large as that observed previously. Although our result increases the efficiency of the $^{37}\mathrm{Cl}$ detector for counting solar \ensuremath{\nu}'s by 6%, its main effect is to reduce uncertainties in this efficiency arising from discrepancies between previous $^{37}\mathrm{Ca}$ \ensuremath{\beta} decay and $^{37}\mathrm{Cl}$(p,n) results.