|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'503'724
Articles rated: 2609
24 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
CCD Photometry of the Globular Cluster Omega Centauri. I. Metallicity of RR Lyrae Stars from Caby Photometry | | Soo-Chang Rey
; Young-Wook Lee
; Jong-Myung Joo
; Alistair Walker
; Scott Baird
; | | Date: |
7 Dec 1999 | | Subject: | astro-ph | | Affiliation: | Center for Space Astrophysics, Yonsei Univ. Korea), Alistair Walker (NOAO/CTIO), Scott Baird (Benedictine College & U. Kansas | | Abstract: | We present new measurements of the metallicity of 131 RR Lyrae stars in the globular cluster Omega Centauri, using the hk index of the Caby photometric system. The hk method has distinct advantages over Delta-S and other techniques in determining the metallicity of RR Lyrae stars, and has allowed us to obtain the most complete and homogeneous metallicity data to date for the RR Lyrae stars in this cluster. For RR Lyrae stars in common with the Delta-S observations of Butler et al. (1978) and Gratton et al. (1986), we have found that our metallicities, [Fe/H](hk), deviate systematically from their Delta-S metallicity, while our [Fe/H](hk) for well observed field RRab stars are consistent with previous spectroscopic measurements. We conclude that this is due to the larger errors associated with the previous Delta-S observations for this cluster. The Mv(RR) - [Fe/H] and period-shift - [Fe/H] relations obtained from our new data are consistent with the evolutionary models predicted by Lee (1991), confirming that the luminosity of RR Lyrae stars depends on evolutionary status as well as metallicity. Using the period - amplitude diagram, we have also identified highly evolved RRab stars in the range of -1.9 < [Fe/H] < -1.5, as predicted from the synthetic horizontal-branch models. | | Source: | arXiv, astro-ph/0001101 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER