Abstract
We have observed two W UMa-type contact binaries, XY Leo and VW Cep, simultaneously with EXOSAT, the VLA, and, in the case of XY Leo, optically. The temporal coverage of each star was sufficient to monitor them throughout two orbital revolutions (P~0.25 days), however, no orbital modulation of either the X-ray or 6 cm data was seen for either star. A large flare from VW Cep was detected, the first such simultaneous flare ever seen on a star other than the Sun. Its behavior before, during, and after the flare is remarkably similar to that found in solar flares. For both stars, it is demonstrated that the 6 cm emission cannot be the result of Bremsstrahlung radiation of the X-ray emitting plasma.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Barden, S. C. 1987, Ap. J., 317, 333.
Cruddace, R. G. and Dupree, A. K. 1984, Ap. J., 277, 263.
Drake, S. A., Simon, T., and Linsky, J. L. 1986, A. J., 91, 1229.
Hughes, V. A. and McLean, B. J. 1984, Ap. J., 278, 716.
Linsky, J. L. and Gary, D. E. 1983 Ap. J., 274, 776.
Marsh, K. A. and Hurford, G. J. 1982, Ann. Rev. Astr. Ap., 20, 497.
Mewe, R. 1986, private communication.
Vilhu, O. and Heise, J. 1986, Ap. J., 311, 937.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1988 Kluwer Academic Publishers
About this paper
Cite this paper
Vilhu, O., Caillault, JP., Neff, J., Heise, J. (1988). Simultaneous Exosat and VLA Observations of the W UMa Binaries, VW Cep and XY Leo: A Flare on VW Cep. In: Havnes, O., Pettersen, B.R., Schmitt, J.H.M.M., Solheim, J.E. (eds) Activity in Cool Star Envelopes. Astrophysics and Space Science Library, vol 143. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-2951-7_30
Download citation
DOI: https://doi.org/10.1007/978-94-009-2951-7_30
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-7827-6
Online ISBN: 978-94-009-2951-7
eBook Packages: Springer Book Archive