2002/03/13 by B. Plez, Bertrand Plez, David L. Lambert +1 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:20020363
published as A and A 386 (2002), 1009 · 10 pages, 7 figures
arxiv created 2002/03/13 · openalex publication_date 2002/05/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
Spatially-resolved high-resolution long-slit spectra of Betelgeuse's circumstellar shell are described for a spectral window centered on the 7699 Å resonance line of neutral potassium. The K i emission from resonance fluorescent scattering of photospheric photons which is mapped out to 50 arcsec from the star is approximately spherically symmetric with a brightness decreasing as , where r is the radial distance from the star. Our measurements together with the earlier theoretical interpretation by Rodgers & Glassgold suggest that the mass loss rate is about y-1. The K i emission is far from homogeneous: intensity inhomogeneities are seen down to the seeing limit of about 1 arcsec and the velocity resolution of about 2 km s-1. There is clear evidence for a thin shell of 50 arcsec radius. This is identified with the weaker circumstellar absorption component known as S2. Estimates are made of the density of K atoms in this shell ( cm-3).