1998A&A...336..527D

Using seven four-hour time series of high-resolution spectra, the binary nature and the oscillations of θ Tuc are investigated. The spectrum is double-lined, proving the binarity. θ Tuc is a binary with a circular orbit and with an anomalous mass ratio q=0.09. The for the first time determined orbital elements are P=7.1036days, K₁=8.6km/s and K₂=95.6km/s. The oscillations of the δ Scuti-type main component are spectroscopically investigated. Line-profile variations are discovered, and radial-velocity variations reveal a main oscillation frequency of f₁=20.27c/d which corresponds to the main oscillation 20.2806c/d in photometry. Another frequency, f₂=18.82c/d found in the spectroscopic data and not present in the photometric dataset, needs to be investigated more profoundly.