First transmission of electrons and ions through the KATRIN beamline

TL;DR

This paper reports the successful commissioning and initial transmission tests of electrons and ions through the KATRIN beamline, marking key milestones in the experiment's setup for neutrino mass measurement.

Contribution

It documents the first successful transmission of electrons and ions through the KATRIN beamline, including system assembly, stability, and performance characterization.

Findings

Successful transmission from all sources tested

System stability established

Performance metrics characterized

Abstract

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. We have successfully achieved transmission from all four sources, established system stability, and characterized many aspects of the apparatus.