https://doi.org/10.1140/epjc/s10052-018-5832-y
Regular Article - Experimental Physics
Calibration of high voltages at the ppm level by the difference of 
Kr conversion electron lines at the KATRIN experiment
1
Helmholtz-Institut für Strahlen- und Kernphysik, Rheinische Friedrich-Wilhelms Universität Bonn, Nussallee 14-16, 53115, Bonn, Germany
2
Institute of Experimental Particle Physics (ETP), Karlsruhe Institute of Technology (KIT), Wolfgang-Gaede-Str. 1, 76131, Karlsruhe, Germany
3
Institut für Physik, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
4
Institute for Data Processing and Electronics (IPE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
5
Institute for Nuclear Research of Russian Academy of Sciences, 60th October Anniversary Prospect 7a, 117312, Moscow, Russia
6
Institute for Technical Physics (ITeP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
7
Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117, Heidelberg, Germany
8
Max-Planck-Institut für Physik, Föhringer Ring 6, 80805, Munich, Germany
9
Technische Universität München, James-Franck-Str. 1, 85748, Garching, Germany
10
Institute for Nuclear Physics (IKP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
11
Laboratory for Nuclear Science, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
12
Center for Experimental Nuclear Physics and Astrophysics, and Dept. of Physics, University of Washington, Seattle, WA, 98195, USA
13
Nuclear Physics Institute of the CAS, v. v. i, 250 68, Řež, Czech Republic
14
Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149, Münster, Germany
15
Department of Physics, Faculty of Mathematics and Natural Sciences, University of Wuppertal, Gauss-Str. 20, 42119, Wuppertal, Germany
16
Department of Physics, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
17
Universidad Complutense de Madrid, Instituto Pluridisciplinar, Paseo Juan XXIII no 1, 28040, Madrid, Spain
18
Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC, 27599, USA
19
Triangle Universities Nuclear Laboratory, Durham, NC, 27708, USA
20
Commissariat à l’Energie Atomique et aux Energies Alternatives, Centre de Saclay, DRF/IRFU, 91191, Gif-sur-Yvette, France
21
University of Applied Sciences (HFD) Fulda, Leipziger Str. 123, 36037, Fulda, Germany
22
Department of Physics, Case Western Reserve University, Cleveland, OH, 44106, USA
23
Institute for Nuclear and Particle Astrophysics and Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
24
Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, 12489, Berlin, Germany
25
Project, Process, and Quality Management (PPQ), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
* e-mail: oliver.rest@uni-muenster.de
Received:
20
February
2018
Accepted:
22
April
2018
Published online:
9
May
2018
The neutrino mass experiment KATRIN requires a stability of 3 ppm for the retarding potential at − 18.6 kV of the main spectrometer. To monitor the stability, two custom-made ultra-precise high-voltage dividers were developed and built in cooperation with the German national metrology institute Physikalisch-Technische Bundesanstalt (PTB). Until now, regular absolute calibration of the voltage dividers required bringing the equipment to the specialised metrology laboratory. Here we present a new method based on measuring the energy difference of two Kr conversion electron lines with the KATRIN setup, which was demonstrated during KATRIN’s commissioning measurements in July 2017. The measured scale factor 
of the high-voltage divider K35 is in agreement with the last PTB calibration 4 years ago. This result demonstrates the utility of the calibration method, as well as the long-term stability of the voltage divider.
© The Author(s), 2018
