2020/11/26 by C. R. O'Dell, C. R. O’Dell, N. P. Abel +1 · 6 citations
Physics and Astronomy · #Abundance (ecology) #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #High resolution #Ionization #Line-of-sight #Low resolution #Resolution (logic) #Spectral line #Spectral resolution #Stellar, planetary, and galactic studies #astro-ph.GA #physics.space-ph
paper · pdf · doi:10.3847/1538-4357/abce57
published in The Astrophysical Journal 907(2), 119 (IOP Publishing) · 9 pages, 2 figures
arxiv created 2020/11/26 · openalex created_date 2020/12/07 · openalex publication_date 2021/02/01 · arxiv updated 2021/02/17 · openalex updated_date 2026/08/05
Abstract We establish that there are two velocity systems along lines of sight that contribute to the emission-line spectrum of the brightest parts of the Orion Nebula. These overlie the Orion-S embedded molecular cloud southwest of the dominant ionizing star ( θ 1 Ori C). Examination of 10 × 10″ samples of high spectral resolution emission-line spectra of this region reveals it to be of low ionization, with velocities and ionization different from the central part of the nebula. These properties jeopardize earlier determinations of abundance and physical conditions since they indicate that this region is much more complex than has been assumed in analyzing earlier spectroscopic studies and argue for use of very high spectral resolution or known simple regions in future studies.