Direct Search for the Neutrino Mass and the KATRIN experiment

par Christian Weinheimer (Universität Münster)

lundi 12 mai 2014, 14:00 → 15:00 Europe/Paris

Amphiteatre (CPPM)

Since the discovery of neutrino oscillation we know that neutrinos have non-zero masses, but we do not know the absolute neutrino mass scale, which is very important for cosmology as well as for particle physics. Complementary to the search for neutrinoless double beta-decay and analyses of cosmological data is the direct search for a non-zero neutrino mass, in which the endpoint spectra of weak decays are studied. The most stringent limits on the neutrino mass originate from investigations of the electron energy spectra of tritium or Re-187 beta-decay near their endpoints. In contrast to the other two methods the direct neutrino mass method does not request further assumptions, it only requires energy and momentum conservation and applies the relativistic energy-momentum relationship. Currently the Karlsruhe Tritium Neutrino experiment KATRIN is under construction and commissioning. It will improve the best limit from the tritium beta decay experiments at Mainz and Troitsk of 2 eV by one order of magnitude probing the region relevant for structure formation in the universe. KATRIN uses a strong windowless gaseous molecular tritium source combined with a huge MAC-E-Filter as electron spectrometer. Data from the commissioning phase I of the spectrometer and detector section will be presented. In addition to a report on the KATRIN experiment and outlook on bolometric experiments using the beta decay of Re-187 or the electron capture of Ho-163 will be given.

Transparents marseille_cppm_weinheimer.pdf