1994A&A...287..509S

We present the results of photometric and spectroscopic observations of the star ζ Cas. The luminosity fluctuations are inside 0.004 magnitude in the u, v and b Stroemgren's filters. For a given night the radial velocity measurements vary inside 1 km/s. We suppose that the observed night to night radial velocity variations are due to a close binarity. The orbital period could be 11.53 days with a 2K amplitude equal 3.6 km/s. The full width at half maximum (FWHM) measurements of the 4552 A SiIII line are variable from night to night inside 0.08 A. After detrending for this variation, a peak appears in the power spectrum at 0.27 day with a half amplitude of 0.01 A possibly due to a non radial g mode. We do not detect the 0.9 d. period determined by Smith (1980). So the only short time variable parameter is the shape of the line profile. This is the main characteristic of a 53 Per type star.