ABSTRACT
We have designed and constructed a superconducting beta spectrometer with a momentum resolution of about 2% and a peak solid angle of 0.5 sr. The performance of the spectrometer is described and the results of calibrations with line sources are presented.
ABSTRACT
We have determined the energy of the J(pi) = 1/2(+), T = 3/2 resonance in 32S(p,p) to be E(p) = 3374.7+/-0.8 keV. This disagrees with the previously accepted value of E(p) = 3370+/-1 keV by Abbondanno et al. [Nuovo Cimento 70A, 391 (1970)] and solves a problem raised by recent observations of unexpected deviations from the isobaric multiplet mass equation. This resonance is also important in calibrating the beta-delayed proton spectra from 33Ar and 32Ar, and our findings may modify previous conclusions.
ABSTRACT
The ratio of L- to K-shell electron captures in light nuclei is particularly sensitive to electron overlap and exchange effects. Calculations of these effects in (7)Be disagree by more than 20%. We report a measurement of the L/K ratio in (7)Be, using a cryogenic microcalorimeter which clearly separates L- and K-shell captures. The obtained L/K ratio of 0.040(6) is less than half that of existing predictions for free (7)Be. The discrepancy is likely due to in-medium effects distorting the L-shell electron orbitals.