27 November 1989 Low Noise Microchannel Plate Detectors For X-Ray Astronomy
Author Affiliations +
The dominant source of internal background in microchannel plate detectors is thought to be due to trace amount of ra-dioisotopes in the detector glass which decay through β-processes. Several manufacturers have begun programs to produce lead glass with greatly reduced amounts of radioisotopes in order to fabricate microchannel plates with lower internal background counting rates. Our laboratory measurements of such plates show that the background rates are substantially lower than in standard microchannel plates. The remaining background rate is consistent with the sum of the rates due to the residual trace level of radioisotopes, cosmic ray interactions in the microchannel plates, and a third, previously unrecognized component which is likely due to MeV γ-rays emitted by the laboratory concrete walls. We discuss the implications the measured background rates have for the sensitivity of the High Resolution Camera (HRC) to be flown on the U.S. Advanced X-ray Astrophysics Facility (AXAF). We compare these predicted rates with those measured in the High Resolution Imager (HRI) which was flown on the Einstein X-ray astronomy observatory.
© (1989) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Michael R. Garcia, Jon H Chappell, Stephen S. Murray, W. Bruce Feller, George W. Fraser, "Low Noise Microchannel Plate Detectors For X-Ray Astronomy", Proc. SPIE 1140, X-Ray Instrumentation in Medicine and Biology, Plasma Physics, Astrophysics, and Synchrotron Radiation, (27 November 1989); doi: 10.1117/12.961809; https://doi.org/10.1117/12.961809


Advances In Microchannel Plate Detectors
Proceedings of SPIE (December 21 1988)
Low-noise and conductively cooled microchannel plates
Proceedings of SPIE (July 01 1990)
After emission in microchannel plate detectors
Proceedings of SPIE (November 01 1990)
Recent studies of lobster-eye optics
Proceedings of SPIE (November 19 1998)
Properties of 100 mm X 100 mm triple stacks of...
Proceedings of SPIE (December 16 1993)

Back to Top