Direct measurement of the Electron - Neutrino Mass via Decay of ¹⁵⁹Dy

The measurement of neutrino mass represents a long - standing major scientific challenge, carrying profound significance for both particle physics and astrophysics. The energy spectra of β - decay or electron capture (EC) in radioactive nuclides can be employed to directly measure neutrino mass. Isotopes with low decay energy are particularly advantageous for enhancing the sensitivity of neutrino mass measurements due to the significantly enhanced decay rate in the endpoint region of the decay energy spectrum. The EC decay process of ¹⁵⁹Dy to ¹⁵⁹Tb exhibits an ultra low decay energy. This presentation proposes using superconducting detectors to study the decay energy spectrum of this process, expecting to achieve a direct measurement of the electron - neutrino mass with sub - eV sensitivity at a 90% confidence level.