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Hubble Space Telescope
GHRS Instrument Science Report 070

GHRS Instrument Science Report 070

"GHRS Dark Noise Monitoring"

Stephen J. Hulbert, Lisa E. Sherbert, and Paul Lee

Abstract excerpted from the Conclusion of the report:

Background dark noise levels for the GHRS have been constant since
launch and continue to be consistent with the original predictions. As
previously seen, the dark noise on Side 1 is less *by almost a factor
of two) than the Side 2 rates and count rates are dependent on
geomagnetic latitude. The particle event detection algorithm currently
used in [STSDAS task] darksum does not appear to be a good predictor
of dark counts from particle event-induced Cerenkov radiation - an
alternated method for rejecting counts due to particle hits is being
investigated. [Many interesting plots included.]