The Electron Capture Decay of 163-Ho to Measure the Electron Neutrino Mass with sub-eV Accuracy (and Beyond)

We have investigated the possibility of measuring the electron neutrino mass with sub-eV sensitivity by studying the electron capture decay of 163-Ho with cryogenic microcalorimeters. In this paper we will introduce an experiment’s concept, discuss the technical requirements, and identify a roadmap to reach a sensitivity of 0.1 eV and beyond.