Context. V1094 Tau is a bright eclipsing binary star with an orbital period close to nine days that contains two stars similar to the Sun. Aims: Our aim is to test models of Sun-like stars using precise and accurate mass and radius measurements for both stars in V1094 Tau. Methods: We present new spectroscopy of V1094 Tau, which we use to estimate the effective temperatures of both stars and to refine their spectroscopic orbits. We also present new, high-quality photometry covering both eclipses of V1094 Tau in the Strömgren uvby system and in the Johnson V-band. Results: The masses, radii, and effective temperatures of the stars in V1094 Tau are found to be MA = 1.0965 ± 0.0040 M?, RA = 1.4109 ± 0.0058 R?, Teff,A = 5850 ± 100 K, MB = 1.0120 ± 0.0028 M?, RB = 1.1063 ± 0.0066 R?, and Teff,B = 5700 ± 100 K. An analysis of the times of mid-eclipse and the radial velocity data reveals apsidal motion with a period of 14 500 ± 3700 years. Conclusions: The observed masses, radii, and effective temperatures are consistent with stellar models for an age ˜6 Gyr if the stars are assumed to have a metallicity similar to the Sun. This estimate is in reasonable agreement with our estimate of the metallicity derived using Strömgren photometry and treating the binary as a single star ([ Fe/H ] = -0.09 ± 0.11). The rotation velocities of the stars suggest that V1094 Tau is close to the limit at which tidal interactions between the stars force them to rotate pseudo-synchronously with the orbital motion. The table of the light curves shown in Fig. 1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A A/578/A25
Context. V1094 Tau is a bright eclipsing binary star with an orbital period close to nine days that contains two stars similar to the Sun. Aims: Our aim is to test models of Sun-like stars using precise and accurate mass and radius measurements for both stars in V1094 Tau. Methods: We present new spectroscopy of V1094 Tau, which we use to estimate the effective temperatures of both stars and to refine their spectroscopic orbits. We also present new, high-quality photometry covering both eclipses of V1094 Tau in the Strömgren uvby system and in the Johnson V-band. Results: The masses, radii, and effective temperatures of the stars in V1094 Tau are found to be MA = 1.0965 ± 0.0040 M?, RA = 1.4109 ± 0.0058 R?, Teff,A = 5850 ± 100 K, MB = 1.0120 ± 0.0028 M?, RB = 1.1063 ± 0.0066 R?, and Teff,B = 5700 ± 100 K. An analysis of the times of mid-eclipse and the radial velocity data reveals apsidal motion with a period of 14 500 ± 3700 years. Conclusions: The observed masses, radii, and effective temperatures are consistent with stellar models for an age ˜6 Gyr if the stars are assumed to have a metallicity similar to the Sun. This estimate is in reasonable agreement with our estimate of the metallicity derived using Strömgren photometry and treating the binary as a single star ([ Fe/H ] = -0.09 ± 0.11). The rotation velocities of the stars suggest that V1094 Tau is close to the limit at which tidal interactions between the stars force them to rotate pseudo-synchronously with the orbital motion. The table of the light curves shown in Fig. 1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A+A/578/A25
