Speaker
Description
The KATRIN experiment probes the effective anti electron neutrino mass by measuring the electrons emitted from the beta decay of molecular tritium T$_2$. The shape of the endpoint region of its kinetic energy spectrum depends the neutrino mass. Recently, the most stringent upper limit of $m_\nu$ = 0.45$\,$eV (90 % C.L.) from direct measurements was reported (Aker et al. 10.1126/science.adq9592). To improve the sensitivity on $m_\nu$ by an order of magnitude, future neutrino mass experiments like KATRIN++ aim to develop new technologies. Sensitivity studies have shown that significant improvements can be made by transitioning from T$_2$ to atomic tritium T.
The final goal is a sub-kelvin magnetic T-trap. The roadmap until then is a multistep approach including the dissociation of T$_2$, various cooling stages and finally the magnetic trap. Different dissociation technologies are currently investigated by the Karlsruhe Mainz Atomic Tritium Experiment (KAMATE). At the moment they are tested with nonradioactive hydrogen. We are comparing thermal-based and plasma-based dissociators. For the latter, we are presenting results from Optical Emission Spectroscopy (OES) combined with Collisional Radiative (CR) models that allow the determination of the atomic density inside the plasma. Furthermore, we report about different detection methods of the hot atomic beams, especially pointing out results of graphene as a beam sensor. Finally, we present an experimental setup proposal for dissociation and trapping of T$_2$ at cryogenic temperatures together with the University of Turku.