Precision electron-capture energy in 202Pb and its relevance for neutrino mass determination

Within the framework of an extensive programme devoted to the search for alternative candidates for the neutrino mass determination, the atomic mass difference between 202Pb and 202Tl has been measured with the Penning trap mass spectrometer ISOLTRAP at the ISOLDE facility at CERN. The obtained value \( Q_{{\rm EC}} = 38.8(43)\) keV is three times more precise than the AME2012 value. While it will probably not lead to a replacement of 163Ho in modern experiments on the determination of the electron-neutrino mass, the electron capture in 202Pb would however allow a determination of the electron-neutrino mass on the few-eV level using a cryogenic micro-calorimeter.