Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-26T04:43:19.422Z Has data issue: false hasContentIssue false
  • English
  • Français

Long-term Starspot Behavior of BY Dra and EV Lac

Published online by Cambridge University Press:  12 April 2016

B.R. Pettersen ,
K. Oláh  and
W.H. Sandmann
B.R. Pettersen
Affiliation:
Institute of Theoretical Astrophysics, University of Oslo, P.O.Box 1029 Blindern, N-0315 Oslo 3, Norway
K. Oláh
Affiliation:
Konkoly Observatory, Hungarian Academy of Sciences, P.O.Box 67, H-1525 Budapest XII, Hungary
W.H. Sandmann
Affiliation:
Department of Physics, Harvey Mudd College, Claremont, CA 91711, USA

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

New starspot photometry of BY Dra and EV Lac, extending over a decade is analyzed in combination with data from the literature to study the long-term behaviour of spottedness on these stars. Both stars show brightness suppression as well as brightness modulation so spots exist both near the poles and at lower latitudes. Polar spots have been continuously present on BY Dra for the last 14 years. (O–C) diagrams for lightcurve minima reveal systematic, sinusoidal variations in BY Dra with a period of 13–14 years. In EV Lac the spots have been located on the same hemisphere for the last ten years.

Type
Part IV Stellar activity
Information
International Astronomical Union Colloquium , Volume 130: The Sun and Cool Stars: activity, magnetism, dynamos , 1991 , pp. 378 - 380
Copyright
Copyright © Springer-Verlag 1991

References

Chugainov, P.F.: 1973, Izv. Krymsk. Astrofiz. Obs. 48, 3 Google Scholar
Vogt, S.S.: 1980, Astrophys. J. 240, 567 CrossRefGoogle Scholar