KATRIN – Direct measurement of ν-masses in the sub-eV range

Abstract

The rlsruhe tium eutrino (KATRIN) experiment is a next-generation direct neutrino mass experiment with sensitivity to sub-eV ν-masses. It combines an ultra-luminous molecular windowless gaseous tritium source with a high resolution electrostatic retarding spectrometer (MAC-E filter) to measure the spectral shape of β-decay electrons close to the T₂ end point at 18.6 keV with unprecedented precision. If no neutrino mass signal is found, the KATRIN sensitivity after 3 years of measurements is m _ν < 0.2 eV (90 % CL.); a ν-mass signal of m _ν = 0.35 (0.30) eV can be measured with 5 (3) σ evidence.

PACS: 23.40.-s Beta decay; double beta decay; electron and muon capture – 14.60.Pq Neutrino mass and mixing