A low energy, high-luminosity, high-resolution double-focusing magnetic beta-ray spectrometer for measuring neutrino rest mass

A spectrometer is described which was reconstructed from an electromagnetic isotope separator. The characteristics of the modified spectrometer, such as stability background resolving power, and luminosity have been tested and determined showing a momentum resolution of 0.8% and luminosity of 0.12 cm/sup 2/ for the 16-23 keV region.<
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