First transmission of electrons and ions through the KATRIN beamline

Understand

The Karlsruhe Tritium Neutrino (KATRIN) experiment is a large-scale effort to probe the absolute neutrino mass scale with a sensitivity of 0.2 eV (90% confidence level), via a precise measurement of the endpoint spectrum of tritium beta decay.

• This work documents several KATRIN commissioning milestones: the complete assembly of the experimental beamline, the successful transmission of electrons from three sources through the beamline to the primary detector, and tests of ion transport and retention.
• In the First Light commissioning campaign of Autumn 2016, photoelectrons were generated at the rear wall and ions were created by a dedicated ion source attached to the rear section; in July 2017, gaseous Kr-83m was injected into the KATRIN source section, and a condensed Kr-83m source was deployed in the transport section.
• In this paper we describe the technical details of the apparatus and the configuration for each measurement, and give first results on source and system performance.