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Survey of candidate gamma-ray sources at TeV energies using a high-resolution Cerenkov imaging system - 1988-1991The steady TeV gamma-ray emission from the Crab Nebula has been used to optimize the sensitivity of the Whipple Observatory atmospheric Cerenkov imaging telescope. Using this method, which is of order 20 times more sensitive than the standard method using a simple non-imaging detector, it is possible to detect the Crab Nebula at a significance level in excess of 6 standard deviations (6 sigma) in under 1 hr on source (with a corresponding time observing a background comparison region); a source one-tenth the strength of the Crab Nebula can be detected at the 4 sigma level after 40 hr on the source (and 40 hr on a background region). A variety of sources have been monitored using this technique over the period 1988-1991, but none were detected apart from the Crab Nebula. Upper limits are presented which in many instances are a factor of 10 below the flux of the Crab Nebula. These upper limits assume steady emission from the source and cannot rule out sporadic gamma-ray emission with short duty cycles.
Document ID
19930041420
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Reynolds, P. T.
(Iowa State Univ. of Science and Technology, Ames, United States)
Akerlof, C. W.
(Michigan Univ. Ann Arbor, United States)
Cawley, M. F.
(St. Patrick's College Maynooth, Ireland)
Chantell, M.
(Whipple Observatory Amado, AZ, United States)
Fegan, D. J.
(Univ. College Dublin, Ireland)
Hillas, A. M.
(Leeds Univ. United Kingdom)
Lamb, R. C.
(Iowa State Univ. of Science and Technology, Ames, United States)
Lang, M. J.
(Univ. College Dublin, Ireland)
Lawrence, M. A.
(Whipple Observatory Amado, AZ, United States)
Lewis, D. A.
(Iowa State Univ. of Science and Technology, Ames, United States)
Date Acquired
August 16, 2013
Publication Date
February 10, 1993
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 404
Issue: 1
ISSN: 0004-637X
Subject Category
Space Radiation
Accession Number
93A25417
Distribution Limits
Public
Copyright
Other

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