Which Stars Are Ionizing the Orion Nebula?

Journal Article · Fri Mar 10 04:00:00 EST 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/AA6198· OSTI ID:22869222

O’Dell, C. R. ^[1]; Kollatschny, W. ^[2]; Ferland, G. J. ^[3]

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1. Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235-1807 (United States)
2. Institut für Astrophysik, Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen (Germany)
3. Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States)

The common assumption that θ{sup 1} Ori C is the dominant ionizing source for the Orion Nebula is critically examined. This assumption underlies much of the existing analysis of the nebula. In this paper we establish through comparison of the relative strengths of emission lines with expectations from Cloudy models and through the direction of the bright edges of proplyds that θ{sup 2} Ori A, which lies beyond the Bright Bar, also plays an important role. θ{sup 1} Ori C does dominate ionization in the inner part of the Orion Nebula, but outside of the Bright Bar as far as the southeast boundary of the Extended Orion Nebula, θ{sup 2} Ori A is the dominant source. In addition to identifying the ionizing star in sample regions, we were able to locate those portions of the nebula in 3D. This analysis illustrates the power of MUSE spectral imaging observations to identify sources of ionization in extended regions.

• OSTI ID: 22869222
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 837; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COMPARATIVE EVALUATIONS
EMISSION
HYDROGEN
IONIZATION
NEBULAE
STARS