Starspot distributions on XY UMa during 1997-2000 from eclipse mapping

Citation
Ta. Lister et al., Starspot distributions on XY UMa during 1997-2000 from eclipse mapping, M NOT R AST, 326(4), 2001, pp. 1489-1498
Citations number
45
Categorie Soggetti
Space Sciences
Journal title
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
ISSN journal
00358711 → ACNP
Volume
326
Issue
4
Year of publication
2001
Pages
1489 - 1498
Database
ISI
SICI code
0035-8711(20011001)326:4<1489:SDOXUD>2.0.ZU;2-T
Abstract
We present narrow-band red light curves and surface maps of the short-perio d RS CVn binary system XY UMa, obtained between 1997 January and 2000 March . The light-curve morphology of this system is known to vary on time-scales of a few days. We have used eclipse-mapping techniques to map the distribu tion of cool starspots on the surface of the primary star. The resulting ma ps show the continued evolution of spot features on time-scales of a few da ys to a week. By comparison with the images of Collier Cameron & Hilditch, we also find evidence for longer term trends, including a decline to an act ivity minimum during 1997 and a rise in activity during 1998-2000. We also find marginal evidence from the O-C ephemeris curves for a periodicity and a peak corresponding to the time of activity minimum.