Kinematic structure of the atmosphere and envelope of the post-AGB star HD56126

Abstract

We present results of an analysis of the optical spectrum of the post-AGB star HD56126 (IRAS 07134+1005) based on observations made with the echelle spectrographs of the 6-m telescope with spectral resolutions of R=25000 and 60000 at 4012-8790 AA. The profiles of strongest lines (HI; FeII, YII, BaII absorptions, etc.) formed in the expanding atmosphere at the base of the stellar wind have complex and variable shapes. To study the kinematics of the atmosphere, the velocities of individual features in these profiles must be measured. Differential line shifts of up to Vr=15-30 km/s have been detected from the lines of metals and molecular features. The star's atmosphere simultaneously contains both expanding layers and layers falling onto the star. A comparison of the data for different times demonstrates that both the radial velocity and the velocity pattern in whole are variable. The position of the molecular spectrum is stable, implying stability of the expansion velocity of the circumstellar envelope around HD56126 detected in observations in the C_2 and NaI lines.

16 pages, 7 figures, 1 table

References in corpus (1)

• IR-source IRAS20508+2011: spectral variability of the central star

Cited by in corpus (8)

• First detection of surface magnetic fields in Post-AGB stars : the cases of U Monocerotis and R Scuti
• Circumstellar envelope manifestations in the optical spectra of evolved stars
• A pre-explosion extended effervescent zone around core collapse supernova progenitors
• A pre-explosion effervescent zone for the circumstellar material in SN 2023ixf
• Spectral variability of the IR-source IRAS 01005+7910 optical component
• A Phenomenological Model for the Extended Zone Above AGB Stars
• Peculiarities of the atmosphere and envelope of a post-AGB star, the optical counterpart of IRAS 23304+6347
• Spectroscopy of supergiants with infrared excess: results of 1998-2018