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The X-Ray Orbital Lightcurve of AR Lac

Parmar, A. N.; White, N. E.; Culhane, J. L. +1 more

Using the EXOSAT observatory we have obtained the X-ray light curve of the 2 day eclipsing RS CVn binary system AR Lac continuously around one complete binary cycle. A deep minimum centered on primary eclipse is seen in the low energy telescope (0.05-2.0 keV), whereas the ME (1.0-10.0 keV) flux remained constant. This shows that the 5-7 million an…

X-ray and optical observations of the flare star Wolf 630 AB and of VB 8 G.

Tagliaferri, G.; White, N. E.; Doyle, J. G. +1 more

Results from three EXOSAT observations of Wolf 630 AB are reported. Two X-ray flares have been detected, one simultaneous with an Hα flare. During the second observation a large increase in the X-ray flux from the nearby star VB 8 was also detected.

A Large X-ray Flare on σ² Coronae Borealis Observed with EXOSAT

Mewe, R.; Brinkman, A. C.; van den Oord, G. H. J.

We report the observation of a compact flare on σ² Coronae Borealis. The energy requirements for the flare are discussed and we find that current-driven turbulence can produce heating fast enough. During the initial phase of the flare classical transport theory is not applicable.

Coordinated EXOSAT and Optical Observations of HD 36705

White, N. E.; Collier Cameron, A.; Bedford, D. K. +3 more

EXOSAT Detection of a Very Large Flare on EQ Peg

Pallavicini, R.; Kundu, M. R.; Jackson, P. D.

Coronae of Late-Type Stars Observed with EXOSAT

Monsignori-Fossi, B. C.; Landini, M.; Pallavicini, R.

Coordinated EXOSAT and Spectroscopic Observations of Flare Stars and Coronal Heating

Rodono, M.; Butler, C. J.

We present some preliminary results of simultaneous monitoring of the two flare stars, UV Ceti and EQ Peg with EXOSAT and ground based optical spectro-scopy. A strong correlation, found between the Hγ emission and the soft X-ray flux, over several hours of observation of UV Ceti, suggests that much of the low level X-ray flux which has previously …

Simultaneous X-Ray and Photometric Observations of the Flare Star YZ CMi

Doyle, J. G.; Butler, C. J.

Broad-band photometric observations of YZ CMi show a 1.2 magnitude U-band flare, however, simultaneous X-ray observations from EXOSAT show no detectable increase. It is suggested that the energy was dissipated before reaching the corona. Two long duration U-band enhancements detected during the optical monitoring may have been the result of back-h…

Detection of an X-Ray Flare from a Single G Dwarf Star

Piro, L.; Monsignori-Fossi, B. C.; Landini, M. +1 more