2007/08/16 by Ben Davies, R. D. Oudmaijer, René D. Oudmaijer +2 · 34 citations
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics and Star Formation Studies #Emission spectrum #Geometry #Line (geometry) #Nebula #Physics #RADIUS #Radial velocity #Red supergiant #Spectral line #Spectroscopy #Stars #Stellar, planetary, and galactic studies #Supergiant #astro-ph
paper · pdf · doi:10.1086/523692
published in The Astrophysical Journal 671(2), 2059-2067 (IOP Publishing) · 22 pages, 9 figures, accepted for publication in ApJ. B&W-optimized version can be downloaded from http://www.cis.rit.edu/~bxdpci/pubs.html
arxiv created 2007/08/16 · openalex publication_date 2007/12/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present NAOMI/OASIS adaptive-optics-assisted integral-field spectroscopy of the transitional massive hypergiant IRC +10420, an extreme mass-losing star apparently in the process of evolving from a red supergiant toward the Wolf-Rayet phase. To investigate the present-day mass-loss geometry of the star, we study the appearance of the line emission from the inner wind as viewed when reflected off the surrounding nebula. We find that, contrary to previous work, there is strong evidence for wind axisymmetry, based on the equivalent width and velocity variations of Hα and Fe II λ6516. We attribute this behavior to the appearance of the complex line profiles when viewed from different angles. We also speculate that the Ti II emission originates in the outer nebula in a region analogous to the strontium filament of η Carinae, based on the morphology of the line emission. Finally, we suggest that the present-day axisymmetric wind of IRC +10420, combined with its continued blueward evolution, is evidence that the star is evolving toward the B[e] supergiant phase.