CCD Photometry of the RR LYRAE Stars in NGC 4147
We report the results of CCD V and R photometry of the RR Lyrae starsknown in NGC 4147. The periodicities of most variables are revised and newephemerides are calculated. The Blazhko effect has been detected in V2 and V6.Three previously reported variables; V5, V9, and V15 are found to be non-variab...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2004 |
| País: | México |
| Institución: | Universidad Nacional Autónoma de México |
| Repositorio: | Redalyc-UNAM |
| OAI Identifier: | oai:redalyc.org:57140207 |
| Acceso en línea: | https://www.redalyc.org/articulo.oa?id=57140207 |
| Access Level: | acceso abierto |
| Palabra clave: | Física, Astronomía y Matemáticas STARS: VARIABLES: RR LYRAE GLOBULAR CLUSTERS: NGC 4147 |
| Sumario: | We report the results of CCD V and R photometry of the RR Lyrae starsknown in NGC 4147. The periodicities of most variables are revised and newephemerides are calculated. The Blazhko effect has been detected in V2 and V6.Three previously reported variables; V5, V9, and V15 are found to be non-variable.A new variable V18 was discovered with a period of 0.49205 days and an amplitudeof 0.15 mag. Using the approach of Fourier decomposition of the light curves, thephysical parameters of the RRab and RRc variables were estimated. The clusteris of the Oosterho type I. With the newly values [Fe/H]=1:22 0:31 and 16:8 1:3 kpc, the cluster fits very well into the Oosterhoff type-metallicity and metallicity-temperaturesequence found in globular clusters. A comparison with ZAHB modelsindicates that the RRab stars have not yet evolved off the horizontal branch, a resultconsistent with the mean period of the RRab variables and with the metallicity ofthe cluster derived in this work. |
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