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1000 GeV gamma rays from Cygnus X-3: An updateMeasurements of 1000 GeV gamma-rays from Cygnus X-3 made with the University of Durham facility at Dugway, Utah in 1981/82 are reviewed. The light curve of the 4.8 hour modulated emission is updated and shows evidence significant at the 4.4 sigma level for strong emission (9% of the cosmic ray rate) at phase 0.625 and less significant (1.4 sigma level) indications of weaker emission (3% of the cosmic ray rate) at phase 0.125. The effect constituting the excess on the few nights showing the strongest emission appears to arise from the smallest Cerenkov light signals suggesting a steep gamma-ray spectrum. The 1982 data have been searched unsuccessfully for evidence of emission at phase 0.2, in coincidence with the results from the ultra-high energy (extensive Air Showers (EAS) measurements in 1979-1982. A systematic investigation of a long term variation in the strength of the peak of the 4.8 hr modulated 1000 GeV gamma-ray emission has been made. We find that in addition to the approximately 34 d variation reported by us previously, a stronger effect exists at around 19d.
Document ID
19850025612
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Chadwick, P. M.
(Durham Univ.)
Dowthwaite, J. C.
(Durham Univ.)
Kirkman, I. W.
(Durham Univ.)
Mccomb, T. J. L.
(Durham Univ.)
Orford, K. J.
(Durham Univ.)
Turver, K. E.
(Durham Univ.)
Date Acquired
August 12, 2013
Publication Date
August 1, 1985
Publication Information
Publication: 19th Intern. Cosmic Ray Conf - Vol. 1
Subject Category
Space Radiation
Report/Patent Number
OG-2.1-8
Report Number: OG-2.1-8
Accession Number
85N33925
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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