München 2019 – wissenschaftliches Programm
HK 53.3: Vortrag
Donnerstag, 21. März 2019, 14:45–15:00, HS 12
Commissioning and calibration of a precision high voltage divider for the electron cooler at CRYRING@ESR — •Daniel Winzen1, Ilian Denesjuk1, Volker Hannen1, Wilfried Nörtershäuser2, Hans-Werner Ortjohann1, Oliver Rest1, and Christian Weinheimer1 — 1WWU Münster — 2TU Darmstadt
In high precision experiments at ion storage rings the velocity of the ions is a critical
quantity. For measurements at CRYRING@ESR (GSI/FAIR) the electron cooler determines the ion
velocity and momentum spread of the stored ions by superimposing the ion beam with a
mono-energetic electron beam. Therefore, a precise knowledge of the acceleration voltage used to produce the
electron beam is essential for the accuracy of the experiments. At the University of
Münster we constructed a precision divider for voltages up to 35 kV with a
similar design to the well-established and tested KATRIN dividers (K35 and K65) that were
developed in Münster in cooperation with the PTB.
We will present calibration and stability measurements that characterize the performance of the high voltage divider. With a novel absolute calibration method the voltage dependency of the dividers scale factors could be measured to the ppm-level. As a consequence, it is possible to conduct ppm-precise voltage measurements over the whole 35 kV range of the divider. This work was supported by BMBF under contract number 05P15PMFAA, GSI F&E project MSWEIN1416 and HGS-HIRe for FAIR.