Bonn 2010 – wissenschaftliches Programm
HK 22.4: Vortrag
Dienstag, 16. März 2010, 15:00–15:15, HG IX
A novel liquid nitrogen fill level meter for the AGATA triple cluster detector — •Daniel Lersch1, Benedikt Birkenbach1, Bart Bruyneel1, Herbert Hess1, Jürgen Eberth1, Gheorghe Pascovici1, Peter Reiter1, Heinz Georg Thomas2, and Andreas Wiens1 — 1Institut für Kernphysik, Universität zu Köln — 2CTT, Montabaur
The final Advanced Gamma Tracking Array (AGATA) will comprise 60 triple cluster detectors. Each cluster consists of three 36-fold segmented HPGe-crystals which are operated at temperatures below 80 K. Thus cooling the detectors with liquid nitrogen and a direct monitoring of the liquid nitrogen level inside the detector dewar is a desirable, crucial feature for operating the spectrometer. A novel liquid nitrogen fill level meter is based on a capacity measurement which is enabled by including a conducting cylinder into the dewar of the cryostat. The fill level dependent capacity difference of less then 10 % between full and empty is converted by a C/V-transducer. To accomodate for the non linear position dependence of the fill level inside the cylinder capacity measurements were performed with AGATA detectors at various inclinations and rotation angles of the detector axis. A supplementary result of the studies are detailed investigations of the liquid nitrogen consumption and the heat loss of the detector during different modes of operation.
Supported by the German BMBF(06K-167, 06KY205I)