EXTENDED WINGS OF THE UV SI-IV, C-IV RESONANCE DOUBLETS AND THE COMPLEX [FE-II] PROFILES IN P-CYGNI

We investigate the formation and the nature of the extended wings of t he UV resonance lines of Si IV 1394, 1402 Angstrom and C IV 1548 and 1 550 Angstrom in the spectrum of the LBV P Cyg. The effects of line ble nding in the neighbourhood of these lines were estimated by means of a grid of theoretical synthetic spectra, computed for the P Cyg model a tmosphere. It is shown that line blending is responsible for the stron g wings of these lines with photospheric origin.Our models are next us ed to treat the problem of the complex structure of [Fe II] lines obse rved by Stahl et al. in the optical spectra of P Cygni. We find that a bsorption, emission and P Cygni-type lines blending with the [Fe II] l ines are responsible for their complex structure. This offers an examp le of how line blending can be wrongly interpreted as evidence for blo bs in a stellar wind.