Crystals of Silver perrhenate have been used for the first time in the bolometric measurement of the spectrum of 187Re in view of the determination of the electron antineutrino mass. The temperature rise has been measured by means of Neutron Transmutation Doped and of P implanted silicon thermistors. The energy scale has been calibrated using the K lines of Mn and with the fluorescent L lines of Sn. Bolometers made by crystals of masses from ~250 to ~500 µg have been rum with FWHM resolutions on the Mn lines ranging from 25 to 60 eV. The end point of the spectrum has been located at 2460±5stat±10syst eV. The measured half lifetime is of 43±4stat±3syst Gyr in good agreement with the values obtained geochemically from the buildup of 187Os in rhenium samples. The sensitivity on the measurement on a non-zero neutrino mass achievable with these bolometers is discussed.
Bolometric Measurements of Beta Decay Spectra of 187Re with Crystals of Silver Perrhenate
Margesin, Benno;Zen, Mario
1999-01-01
Abstract
Crystals of Silver perrhenate have been used for the first time in the bolometric measurement of the spectrum of 187Re in view of the determination of the electron antineutrino mass. The temperature rise has been measured by means of Neutron Transmutation Doped and of P implanted silicon thermistors. The energy scale has been calibrated using the K lines of Mn and with the fluorescent L lines of Sn. Bolometers made by crystals of masses from ~250 to ~500 µg have been rum with FWHM resolutions on the Mn lines ranging from 25 to 60 eV. The end point of the spectrum has been located at 2460±5stat±10syst eV. The measured half lifetime is of 43±4stat±3syst Gyr in good agreement with the values obtained geochemically from the buildup of 187Os in rhenium samples. The sensitivity on the measurement on a non-zero neutrino mass achievable with these bolometers is discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
