Infrared Observations of the Star R Cas
Abstract
We present our JHKLM photometry for R Cas performed during 1988-2000. The pulsation period of R Cas is P = 429.6 days, with the maximum IR brightness lagging behind the maximum visual brightness by 0.2 P. The amplitude of light variations appreciably decreases with increasing wavelength at lambda < 3 micrometers. At lambda > 3 micrometers, this decrease virtually ceases. There is a step on the ascending branch of IR JHK brightness. The K-L color index increases linearly with K magnitude: KL = 0.304 K + 1.20 mag. The color temperature dependence, T_{K-L} = f(K), is also linear: T_{K-L} = (-622 K + 1100) K. In going from minimum to maximum, the K flux (as well as the bolometric flux) from the star and its color temperature T_{K-L} increase by a factor of 2.2 and 1.3, respectively.
- Publication:
-
Astronomy Letters
- Pub Date:
- May 2001
- DOI:
- 10.1134/1.1368702
- Bibcode:
- 2001AstL...27..324N
- Keywords:
-
- VARIABLE AND PECULIAR STARS