UBVRI photometry of FK Com.
Abstract
The light curves in five Johnson photometry colors are given. The period of photometric variability (2.400d) is confirmed, although some systematic drifts of the light curves that are noticeable in less than three weeks also seem to be present. The flare activity is found to increase the noise of the light curves, especially at shorter wavelengths. It is noted that the light variation of about 0.08 in V can be explained by a longitudinally asymmetric region of dark spots covering no less than 10% of the hemisphere; here, the temperature difference relative to the photosphere is of the order of 500-800 K. The variations of individual colors, however, are not consistent with a unique value of that difference. The V-R and R-I colors at maximum suggest an effective temperature of about 4900 K, which agrees with the low-temperature end in the range of existing spectral classifications.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- December 1981
- Bibcode:
- 1981A&A...104..260R
- Keywords:
-
- Giant Stars;
- Light Curve;
- Stellar Spectrophotometry;
- Ubv Spectra;
- Brightness;
- Colorimetry;
- Stellar Temperature;
- Variable Stars;
- Astrophysics