Título del libro: New Quests In Stellar Astrophysics Iii: A Panchromatic View Of Solar-Like Stars, With And Without Planets
Título del capítulo: Empirical Calibration of the Physical Parameters of Solar-like Stars using uvby-Stromgren Photometry
WILLIAM JOHN SCHUSTER; CARLOS ALFREDO MIGUEL ANGEL CHAVARRIA KLEINHENN; JUAN GABRIEL GARCIA RUIZ;
Autores externos:
Idioma:
Año de publicación:
2013
Palabras clave:
SPECTRAL CLASSIFICATION; BETA PHOTOMETRY; NEIGHBORHOOD; CATALOG; COLOR
Resumen:
We present an empirical calibration of the physical parameters of A, F and early G-type stars of luminosity class V. We have used a statistical approach based on a sample of about 15 000 stars having both uvby-Stromgren photomerty (Hauck & Mermilliod 1998) and spectral types taken from SIMBAD. Stars closer than 70 pc have been considered reddening-free. In this paper we present the results for 1900 stars within 70 pc. Mean unreddened measurements have been used as input to CHORIZOS (Malz-Apellaniz 2004). By assuming ``solar metallicity'' ([Fe/H]=0), we have been able to determine effective temperatures (T-eff) and surface gravities (log g) for each spectral type. We have found a tight correlations among the observations and the derived physical parameters; for example, T-eff can be expressed as a cubic polynomial in (b - y)(0). From the distribution of colors and indices for 128 stars and their associated physical parameters we have proposed an alternative definition for solar-analogs: stars whose classification is G2 V with (b - y)(0), = 0.3927 +/- 0.0190, (m(1))(0) = 0.1901 +/- 0.0143, and (c(1))(0) = 0.3302 +/- 0.0388, T-eff = 5930 +/- 145 K, and log g = 4.70 +/- 0.33. These values are consistent with previous empirical results; however, (m(1))(c), differs from a recent model-based value for this index derived by Melendez et al. (2010). This discrepancy points out the actual solar metallicity problem. We suggest that our sample of solar analogs could be useful for searches of solar twins and exoplanets.
Entidades citadas de la UNAM:
ISBN:
9781583818282
Editorial:
ASTRONOMICAL SOC PACIFIC
Tipo de producto:
Proceedings Paper
