HIGH-RESOLUTION SPECTROSCOPY OF 31-PEGASI - THE H-GAMMA AND HE-I-4471LINE VARIATIONS

We present high-resolution HeI 4471, MgII 4481 and H gamma line profil es of the Be star 31 Peg obtained simultaneously at four observing dat es. In this paper we focus on the HeI 4471 line and on the absorption wings of the H gamma line which showed important variations. Models of static stellar atmospheres were calculated to determine the photosphe ric parameters of the underlying star. However, non-static and out of radiative equilibrium models are needed to better understand the struc ture of the atmosphere of 31 Peg and the characteristics of the observ ed He I 4471 and H gamma lines. The implication of deep atmospheric la yers in the mass-loss phenomena of Be stars is suggested.