V380 Ori - A Herbig Ae/Be star at an early stage of envelope formation: Hydrogen-line profiles

We continue to analyze the spectrum of the Herbig Ae/Be star V380 Ori. The hydrogen-line profiles in the spectra of V380 Ori, BF Ori, and gamma Cas sh ell stars (XX Oph and Pleione) are compared. We analyze the three-component model that consists of optically thick and optically thin (in continuum) e nvelopes around an AO star with a luminosity close to the ZAMS luminosity. The star manifests itself only in the hydrogen-line wings. The emission she ll changes its luminosity and shape, which shows up in highly variable brig ht emission lines of gases and metals. The optically thick envelope is more stable. The origin, luminosity, and instability of the envelopes are relat ed to nonstationary accretion from a cold protoplanetary disk. The chemical composition of the envelopes lends support to this version.