Line profile analysis of the δ Scuti star HD 2724≡BB Phe: mode identification and amplitude variations
نویسندگان
چکیده
The line profile variations of the δ Scuti star HD 2724≡BB Phe were studied on the basis of new 189 high– resolution spectrograms covering 52 hours of observations on a baseline of 8.3 days. By combining these results with those of a previous campaign 13 pulsation modes were identified: 5 of them are both photometric and spectroscopic, 3 are purely spectroscopic and 5 purely photometric. For the first time it was possible to compare spectroscopic data taken in two different seasons: 6 modes were found to be common to both datasets and furthermore strong amplitude variations of the excited modes were detected. The fit of the line profile variations with a model of non-radial pulsating star allowed us to obtain a reasonable estimate of the inclination of the rotational axis and to propose the `, m typing of the spectroscopic modes. The frequency content resembles that of 4 CVn, a δ Sct star with similar physical parameters.
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