The liquid nitrogen fill level meter for the AGATA triple cluster detector

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 640; no. 1; pp. 133 - 138
• Main Authors: Lersch, Daniel, Pascovici, Gheorghe, Birkenbach, Benedikt, Bruyneel, Bart, Eberth, Jürgen, Hess, Herbert, Reiter, Peter, Wiens, Andreas, Georg Thomas, Heinz
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-06-2011
• Subjects: Capacitance; Clusters; Cryostats; Detectors; Dewars; Gamma ray instruments; Liquid nitrogen; LN 2 fill level meter; Measuring instruments; Meters; Segmented HPGe detectors; Segmented HPGe detectors; Gamma ray instruments; LN 2 fill level meter
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2011.02.080

A novel liquid nitrogen fill level meter has been put into operation for the all-position dewar of the triple cluster detector of the Advanced GAmma Tracking Array. The new device is based on a capacitance measurement between a metallic cylindrical tube inside the dewar and the inner wall of the cryostat. The fill level dependent capacitance is converted by a
C/
V-transducer into a DC voltage signal. Direct monitoring of the LN
2 level inside the detector dewar has been performed with several AGATA detectors at various inclinations and rotation angles of the detector axis. The time-dependent LN
2 consumption is an additional quantity used to survey the status of the cryostat. Supplementary results are the investigations of the LN
2 consumption and the heat loss of the detector during different modes of operation.