Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Full Refereed Journal Article (PDF/Postscript)
· Full Refereed Scanned Article (GIF)
· On-line Data
· References in the article
· Citations to the Article (11) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (6)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Ultraviolet light curves of beta Lyrae: Comparison of OAO A-2, IUE, and Voyager Observations
Authors:
Kondo, Yoji; McCluskey, George E.; Silvis, Jeffery M. S.; Polidan, Ronald S.; McCluskey, Carolina P. S.; Eaton, Joel A.
Affiliation:
AA(NASA. Goddard Space Flight Center, Greenbelt, MD, US), AB(NASA. Goddard Space Flight Center, Greenbelt, MD, US), AC(Catholic Univ., Washington, DC, US), AD(Catholic Univ., Washington, DC, US), AE(Pennsylavania State Univ., Fogelsville, PA, US), AF(Pennsylavania State Univ., Fogelsville, PA, US)
Publication:
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 421, no. 2, p. 787-799 (ApJ Homepage)
Publication Date:
02/1994
Category:
Astronomy
Origin:
STI
NASA/STI Keywords:
ECLIPSING BINARY STARS, LIGHT CURVE, SPACEBORNE ASTRONOMY, STELLAR ENVELOPES, STELLAR SPECTRA, ULTRAVIOLET ASTRONOMY, ULTRAVIOLET SPECTRA, ASTRONOMICAL SPECTROSCOPY, OAO 2, VOYAGER PROJECT
DOI:
10.1086/173691
Bibliographic Code:
1994ApJ...421..787K

Abstract

The six-band ultraviolet light curves of beta Lyrae obtained with the Orbiting Astronomical Observatory (OAO) A-2 in 1970 exhibited a very unusual behavior. The secondary minimum deepened at shorter wavelength, indicating that one was not observing light variations caused primarily by the eclipses of two stars having a roughly Planckian energy distribution. It was then suggested that the light variations were caused by a viewing angle effect of an optically thick, ellipsoidal circumbinary gas cloud. Since 1978 beta Lyrae has been observed with the International Ultraviolet Explorer (IUE) satellite. We have constructed ultraviolet light curves from the IUE archival data for comparison with the OAO A-2 results. We find that they are in substantial agreement with each other. The Voyager ultraviolet spectrometer was also used to observe this binary during a period covered by IUE observations. The Voyager results agree with those of the two other satellite observatories at wavelengths longer than about 1350 A. However, in the wavelength region shorter than the Lyman-alpha line at 1216 A, the light curves at 1085 and 965 A show virtually no light variation except an apparent flaring near phase 0.7, which is also in evidence at longer wavelengths. We suggest that the optically thick circumbinary gas cloud, which envelops the two stars completely, assumes a roughly spherical shape when observed at these shorter wavelengths.

Printing Options

Print whole paper
Print Page(s) through

Return 600 dpi PDF to Acrobat/Browser. Different resolutions (200 or 600 dpi), formats (Postscript, PDF, etc), page sizes (US Letter, European A4, etc), and compression (gzip,compress,none) can be set through the Printing Preferences


More Article Retrieval Options

HELP for Article Retrieval
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints