A Spectroscopic-Photometric Analysis of the Binary System HR1300

M.E. VERAMENDI; J.F. GONZÁLEZ

Pucón

Congreso; XI Latin-American Regional IAU Meeting - LARIM 2005; 2005

Unión Astronómica Internacional (IAU) - Sociedad Chilena de Astronomía

We present an observational analysis of the eclipsing double-lined spectroscopic binary HR 1300=GW Eri. Twenty two spectra with resolution R=35000 were obtained with the 2.15 m telescope and the bench echelle spectrograph EBASIM of the CASLEO. We measured radial velocities for both stellar components by cross-correlations using the IRAF task fxcor. We used as template an observed spectrum of a low rotation star (HR8641) taken from ELODIE database, which has a similar spectral resolution. This template was previously convolved with an appropiate rotational profile. From our light and radial velocity curves we derived orbital and physical parameters for the system using the Wilson & Devinney code. Assuming a temperature of 9000 K for the primary component, as estimated from the spectral type, we obtained for the secondary companion a temperature of 8680 +- 30 K. The resulting values for absolute masses and radii were 1.797+-0.006 Msun and 1.811+-0.008 Rsun for the primary component, and 1.779+-0.011 Msun and 1.786+-0.016 Rsun for the secondary. The comparison with theoretical stellar models of Girardi et al. (2000, A&AS 141, 371) for solar composition suggests an age of 10^8.7 yr. However, despite the high precision of the calculated masses and radii, the great similarity of the two stellar components prevents us from using this system as a test for stellar models.