D. Ballereau et al., HIGH-RESOLUTION SPECTROSCOPY OF SOUTHERN AND EQUATORIAL BE STARS - FLUX EXCESS AT LAMBDA-4471 ANGSTROM, Astronomy & Astrophysics. Supplement series, 111(3), 1995, pp. 423-455
We present a catalogue of high-resolution He I 4471, Mg II 4481 and H
gamma line profiles observed simultaneously for 37 southern and equato
rial Be stars. In this paper are focus on the He I 4471 line, which is
studied using non-LTE model line profiles. A systematic difference is
found between the observed and the theoretical He I 4471 line equival
ent widths. This difference strongly correlates with the fly emission
and we interpret it as being due mainly to the veiling effect produced
by the continuum emission excess originating in the circumstellar env
elope. To determine the continuum flux excess we use two methods. One
method enables us to obtain simultaneously the V sin i parameter. The
flux excess we determined is overestimated by about 9% on average, bec
ause in the line profile analysis we neglected the gravity darkening e
ffect due to stellar rotation. We find that 14 program stars present t
wo possible solutions for V sin i. The second solution is, on average,
14% smaller and produces a small residual or emission-like difference
between the observed He I 4471 line profile and the model profile.