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The unusual helium variable AM Canum VenaticorumThe unusual variable star AM CVn has puzzled astronomers for over 40 years. This object, both a photometric and spectroscopic variable, is believed to contain a pair of hydrogen-deficient white dwarfs of extreme mass ratio, transferring material via an accretion disk. We examine the photometric properties of AM CVn, analyzing 289 hours of high-speed photometric data spanning 1976 to 1992. The power spectrum displays significant peaks at 988.7, 1248.8, 1902.5, 2853.8, 3805.2, 4756.5, and 5707.8 microHz (1011.4, 800.8, 525.6, 350.4, 262.8, 210.2, and 175.2 s). We find no detectable power at 951.3 microHz (1051 s), the previously reported main frequency. The 1902.5, 2853.9, and 3805.2 microHz peaks are multiplets, with frequency splitting in each case of 20.77 +/- 0.05 microHz. The 1902.5 microHz seasonal pulse shapes are identical, within measurement noise, and maintain the same amplitude and phase as a function of color. We have determined the dominant frequency to be 1902.50902 +/- 0.00001 microHz with dot P = +1.71 (+/- 0.04) x 10(exp -11) s/s. We discuss the implications of these findings on a model for AM CVn.
Document ID
19950061706
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Provencal, J. L.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Winget, D. E.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Nather, R. E.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Robinson, E. L.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Solheim, J.-E.
(Universitetet i Tromso Tromso, Norway)
Clemens, J. C.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Bradley, J. L.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Kleinman, S. J.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Kanaan, A.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Claver, C. F.
(McDonald Observatory, Texas Univ. Austin, TX, United States)
Date Acquired
August 16, 2013
Publication Date
June 1, 1995
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 445
Issue: 2
ISSN: 0004-637X
Subject Category
Astrophysics
Accession Number
95A93305
Funding Number(s)
CONTRACT_GRANT: NSF AST-86-00507
CONTRACT_GRANT: NSF AST-90-13978
CONTRACT_GRANT: NSF AST-85-52456
CONTRACT_GRANT: NSF AST-90-13368
CONTRACT_GRANT: NSF AST-92-17988
CONTRACT_GRANT: NSF AST-87-12249
CONTRACT_GRANT: NSF AST-88-13572
Distribution Limits
Public
Copyright
Other

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