Fourier Decomposition and Physical Parameters of the RR Lyrae Stars in the Globular Cluster NGC 4833
Abstract
We present a preliminary analysis of the RR Lyrae stars in the Globular Cluster NGC 4833. Images were obtained from January through June 2011 with the Southeastern Association for Research in Astronomy 0.6-meter telescope located at Cerro Tololo Interamerican Observatory. The image subtraction method of Alard & Lupton (1998) was used to both search for variable stars in the cluster and to produce light curves of each of the variables stars found. In total 17 RR Lyrae variables we found in our 10'X10' field of view, these included 10 variables of type RRab and 7 of type RRc. Using Fourier decomposition of the light curves of these variables we found the mean iron abundance to be [Fe/H]=-1.67+/-0.13. The mean absolute V-magnitude and log of effective temperature of the RRab variables were 0.65+/-0.07 and 3.8088+/-0.0045, respectively. For the RRc variables we found the mean absolute V-magnitude, log of the effective temperature, and helium abundance to be 0.67+/-0.03, 3.8560+/-0.0014, and 0.243+/-0.005, respectively. The cluster was also found to be of the Oosterhoff type II.
- Publication:
-
American Astronomical Society Meeting Abstracts
- Pub Date:
- June 2013
- Bibcode:
- 2013AAS...22211512M