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arXiv · 2008.13259

Extraplanar gas in Edge-on Galaxies traced by SOFIA observations of [C II]

William T. Reach·Dario Fadda·Richard J. Rand·Gordon J. Stacey
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Abstract

Bursts of localized star formation in galaxies can levitate material from their midplanes. Spiral galaxies that are edge-on allow clear distinction of material that is levitated off the galaxies' midplanes. We used SOFIA to measure the vertical distribution of [C II] 157.7 micron line emission for two nearby, edge-on galaxies, NGC 891 and NGC 5907. We find that for the central region and actively-star-forming regions in the northern portion of NGC 891, and for NGC 5907, a thin (0.3 kpc) disk is supplemented by a thick disk with an exponential scale height of about 2 kpc. The [C II] is far more extended than mid-infrared emission (0.1 kpc, tracing present-day massive star formation) but not as extended as the H I (100 kpc, tracing low-metallicity circum/inter-galactic matter). The extraplanar [C II] may arise in walls of chimneys that connect the disk to the halo.

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William T. Reach, Dario Fadda, Richard J. Rand, Gordon J. Stacey. 2020-08-30. Extraplanar gas in Edge-on Galaxies traced by SOFIA observations of [C II]. https://doi.org/10.3847/1538-4357%2Fabb402

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