NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Performance of bismuth germanate active shielding on a balloon flight over AntarcticaThe GRAD (Gamma-Ray Advanced Detector) gamma-ray spectrometer was flown on a balloon at an altitude of 36.6 km over Antarctica on January 8-10, 1988, where it was used to make observations of SN 1987A. The performance of the bismuth germanate (BGO) active shielding in the near-space environment over Antarctica is examined. The promised effectiveness of this shielding in the suppression of unwanted background has been demonstrated. The BGO-shielded GRAD spectrometer detected gamma-ray lines with fluxes of 0.002/sq cm sec from SN 1987A in a radiation background approximately a factor of 4 more intense than that over Alice Springs, Australia. This level of sensitivity indicates that BGO is at least as effective as CsI when used as active shielding. Isomerism is common, both in the bismuth and germanium regions of the nuclear chart, but is found to be less of a problem for background suppression in the latter region than in the former.
Document ID
19900056060
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Rester, A. C.
(Florida Univ. Alachua, FL, United States)
Coldwell, R. L.
(Florida, University Alachua, United States)
Trombka, J. I.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Starr, R.
(NASA Goddard Space Flight Center Greenbelt, MD; Catholic University of America, Washington, DC, United States)
Eichhorn, G.
(Steward Observatory Tucson, AZ, United States)
Date Acquired
August 14, 2013
Publication Date
April 1, 1990
Publication Information
Publication: IEEE Transactions on Nuclear Science
Volume: 37
ISSN: 0018-9499
Subject Category
Astronomy
Accession Number
90A43115
Funding Number(s)
CONTRACT_GRANT: N00014-87-G-1259
CONTRACT_GRANT: NSG-5066
CONTRACT_GRANT: NSF DPP-87-15809
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available