Detection of 187Re beta decay with a cryogenic microcalorimeter. Preliminary results

Abstract 187 Re, being the nuclide with the lowest known Q -value for β decay is the best candidate to set a limit to the antineutrino mass in a total absorption experiment. It is reported a preliminary measure of the end-point of the decay, that was obtained with a cryogenic microcalorimeter made up of a superconducting rhenium crystal and a germanium thermistor. Limits and possible improvements of the detector are discussed.