Light variations of massive stars (alpha Cygni variables). XII. The photometric history of the G8Ia+ hypergiant V 766 CEN (= HR 5171A) during the years 1953-1991 and its interpretation.
Abstract
VBLUW photometry of the G8 Ia(+) hypergiant V 766 Cen (= HR 5171A) made in the interval 1980-1991 is presented and discussed, together with UBV photometry taken from the literature, which goes back in time until 1953. The star shows a very strong reddening of about 0.65 m between 1953 and 1981, a brightness oscillation with a quasi-period of 494 d, in the interval 1973-1991, and a drop in brightness between 1973 and 1977. Whether the strong reddening is caused by an increasing circumstellar dust density or by evolution to the red in the HR diagram is discussed. The radial velocity curve (1979-1981) appears to be in phase with the light curve. This peculiar behavior is shared with the variable F-type supergiant BL Tel(F). The radius variation amounts to about 8 percent.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- April 1992
- Bibcode:
- 1992A&A...257..177V
- Keywords:
-
- F Stars;
- Massive Stars;
- Stellar Luminosity;
- Supergiant Stars;
- Variable Stars;
- Color-Color Diagram;
- Interstellar Extinction;
- Light Curve;
- Radial Velocity;
- Stellar Oscillations;
- Stellar Spectrophotometry;
- Ubv Spectra;
- Astrophysics