# Neutrino 2020

June 22, 2020 to July 2, 2020
US/Central timezone

## Measurement and modelling of the energy loss function of 18.6 keV electrons due to scattering processes in the tritium source of KATRIN

Not scheduled
10m
Poster

### Speakers

Lutz Schimpf (Karlsruhe Institute of Technology) Rudolf Sack (Westfaelische Wilhelms-Universitaet Muenster)

### Description

The Karlsruhe Tritium Neutrino experiment (KATRIN) is targeted to measure $m(\nu_e)$ with a sensitivity of 200 meV (90% C.L.).
To determine the neutrino mass, the integrated $\beta$-spectrum of tritium is measured close to the endpoint and a fit to the data, comprising the neutrino mass as a free parameter, is performed. A number of systematic effects need to be taken into account in the analysis. One of the major effects is the energy loss from inelastic scattering of beta-electrons with the source gas.
The corresponding energy loss function can be measured by means of an electron gun producing quasi-monoenergetic electrons at 18.6 keV with very small angular spread both in cw and pulsed mode. A new semi-empirical model has been developed based on the experimental data.
This contribution presents the new model and its impact on the KATRIN neutrino mass sensitivity.

### Mini-abstract

A new semi-empirical energy loss model is presented for 18.6 keV electrons scattering off T2 at 30 K

Experiment/Collaboration KATRIN

### Primary authors

Lutz Schimpf (Karlsruhe Institute of Technology) Rudolf Sack (Westfaelische Wilhelms-Universitaet Muenster)

### Co-authors

Bjoern Lehnert (Lawrence Berkeley National Laboratory) Caroline Rodenbeck (Westfaelische Wilhelms-Universitaet Muenster) Christian Weinheimer (Westfaelische Wilhelms-Universitaet Muenster) Christophe Schwachtgen (Karlsruhe Institute of Technology) Jan Behrens (Karlsruhe Institute of Technology/UNC Chapel Hill) Karol Debowski (University of Wuppertal/Karlsruhe Institute of Technology) Kathrin Valerius (Karlsruhe Institute of Technology) Menglei Sun (University of Washington) Sanshiro Enomoto (University of Washington) Volker Hannen (Westfaelische Wilhelms-Universitaet Muenster)