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arXiv · 1910.05416

Using [CII] 158 micron Emission From Isolated ISM Phases as a Star-Formation Rate Indicator

Jessica Sutter·Daniel A. Dale·Kevin V. Croxall·Eric W. Pelligrini·J. D. T. Smith·Phillip N. Appleton·Pedro Beirao·Alberto D. Bolatto·Daniela Calzetti·Alison Crocker·Ilse De Looze·Bruce Draine·Maud Galametz·Brent A. Groves·George Helou·Rodrigo Herrera-Camus·Leslie K. Hunt·Robert C. Kennicutt·Helene Roussel·Mark G. Wolfire
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Abstract

The brightest observed emission line in many star-forming galaxies is the [CII] 158 micron line, making it detectable up to z~7. In order to better understand and quantify the [CII] emission as a tracer of star-formation, the theoretical ratio between the [NII] 205 micron emission and the [CII] 158 micron emission has been employed to empirically determine the fraction of [CII] emission that originates from the ionized and neutral phases of the ISM. Sub-kiloparsec measurements of the [CII] 158 micron and [NII] 205 micron line in nearby galaxies have recently become available as part of the Key Insights in Nearby Galaxies: a Far Infrared Survey with Herschel (KINGFISH) and Beyond the Peak (BtP) programs. With the information from these two far-infrared lines along with the multi-wavelength suite of KINGFISH data, a calibration of the [CII] emission line as a star formation rate indicator and a better understanding of the [CII] deficit are pursued. [CII] emission is also compared to PAH emission in these regions to compare photoelectric heating from PAH molecules to cooling by [CII] in the neutral and ionized phases of the ISM. We find that the [CII] emission originating in the neutral phase of the ISM does not exhibit a deficit with respect to the infrared luminosity and is therefore preferred over the [CII] emission originating in the ionized phase of the ISM as a star formation rate indicator for the normal star-forming galaxies included in this sample.

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Jessica Sutter, Daniel A. Dale, Kevin V. Croxall, Eric W. Pelligrini, J. D. T. Smith, Phillip N. Appleton, Pedro Beirao, Alberto D. Bolatto, Daniela Calzetti, Alison Crocker, Ilse De Looze, Bruce Draine, Maud Galametz, Brent A. Groves, George Helou, Rodrigo Herrera-Camus, Leslie K. Hunt, Robert C. Kennicutt, Helene Roussel, Mark G. Wolfire. 2019-10-11. Using [CII] 158 micron Emission From Isolated ISM Phases as a Star-Formation Rate Indicator. https://doi.org/10.3847/1538-4357%2Fab4da5

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