SIMBAD references

We are obtaining high signal-to-noise optical spectra and time-series photometry of all known DA white dwarfs around the ZZ Ceti instability strip to derive their atmospheric parameters and masses. In this work we report the fundamental parameters for 13 DA stars using ML1/α=2 model atmospheres and analyze the ZZ Ceti instability strip with a sample of 92 DA white dwarfs. This sample has an average mass of 0.59 ±0.02 M_☉ with a dispersion of 0.15 M_☉. Our study shows that the limits of the ZZ Ceti instability strip depend on the effective temperature and mass of the star.