Robinson, Richard

Contact Email: robinson@pha.jhu.edu
Institute: Johns Hopkins University /
Computer Sciences Corporation
First Coauthor: Thomas B. Ake
Institute: Johns Hopkins University / Computer Sciences Corp
Subject Area: Other (Please Specify Below)
Waveband: Far Ultraviolet
Technique: Spectroscopy
Other: Stellar Activity
Presentation: Poster Display
Title: FUSE Observations of Flares on the active K Dwarf AB Doradus
Abstract: Far-ultraviolet spectra were obtained of the active K dwarf AB Doradus (HD 36705) in 1999 Oct and 1999 Dec, during the calibration and checkout period of the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. The data were obtained using the photon counting (time-tag) observing mode, so the time resolution is restricted only by the S/N required in the analysis. Preliminary analysis of the data has been presented by Ake et al (2000, ApJ, 538, L87), who examined the quiescent spectrum and a large flare event which occurred on 22 Oct. In the present study we examine the flaring activity in more detail. The numerous smaller flare events in the data set are studied and the flare occurrence rate determined. We search the data for continuum flux variations and compare these to enhancements of spectral lines formed at different temperatures in order to determine the temperature distribution of the flares. We also compare the characteristics of the smaller events with those of the large 22 Oct flare to quantitatively understand the effects of flare size.