PNNL

Abstract

The most sensitive direct method to establish the absolute neutrino mass is observation of the endpoint of the tritium beta-decay spectrum. Cyclotron Radiation Emission Spectroscopy (CRES) is a precision spectrographic technique that can probe much of the unexplored neutrino mass range with O(eV) resolution. A lower bound of m(e) & 9(0:1)meV is set by observations of neutrino oscillations, while the KATRIN Experiment { the current-generation tritium beta-decay experiment that is based on Magnetic Adiabatic Collimation with an Electrostatic (MAC-E) lter { will achieve a sensitivity of m(e) . 0:2 eV. The CRES technique aims to avoid the diculties in scaling up a MAC-E lter-based experiment to achieve a lower mass sensitivity. In this paper we review the current status of the CRES technique and describe the Project 8 experiment, a phased absolute neutrino mass experiment that has the potential to reach sensitivities down to m(e) . 40meV using an atomic tritium source.