An Astrophysical Investigation of Radius and Mass Anomalies among Short Period Cepheids.
Abstract
Simultaneous photometric and spectroscopic observations were obtained for the short period Cepheids, SU Cas and TU Cas. Using these observations and a modified Wesselink method, in which the radius is obtained from a relation between the (V-R) color and the surface brightness, the radii of the stars were calculated and compared. The pulsation mode of SU Cas was tested by its position in the period radius diagram. The radius obtained gives weak support to the hypothesis that SU Cas is a first overtone pulsator. The spectroscopic radial velocities of TU Cas were combined with those of other authors and a least squares Fourier fitting technique was applied. The periods (previously obtained only from Fourier analysis of light curves) were confirmed and the time rate of change of the amplitudes of various modes was determined.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- May 1979
- Bibcode:
- 1979PhDT.........3N
- Keywords:
-
- Physics: Astronomy and Astrophysics;
- Astrophysics;
- Cepheid Variables;
- Stellar Mass;
- Least Squares Method;
- Photometry;
- Spectroscopy;
- Spectrum Analysis;
- Astrophysics