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arXiv · 1909.08025

2 mm GISMO Observations of the Galactic Center. I. Dust Emission

Richard G. Arendt·Johannes Staguhn·Eli Dwek·Mark R. Morris·Farhad Yusef-Zadeh·Dominic J. Benford·Attila Kovács·Junellie Gonzalez-Quiles
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Abstract

The Central Molecular Zone (CMZ), covering the inner ~1$^\circ$ of the Galactic plane has been mapped at 2 mm using the GISMO bolometric camera on the 30 m IRAM telescope. The $21''$ resolution maps show abundant emission from cold molecular clouds, from star forming regions, and from one of the Galactic center nonthermal filaments. In this work we use the Herschel Hi-GAL data to model the dust emission across the Galactic center. We find that a single-temperature fit can describe the 160 -- 500 $\mu$m emission for most lines of sight, if the long-wavelength dust emissivity scales as $\lambda^{-\beta}$ with $\beta \approx 2.25$. This dust model is extrapolated to predict the 2 mm dust emission. Subtraction of the model from the GISMO data provides a clearer look at the 2 mm emission of star-forming regions and the brightest nonthermal filament.

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Richard G. Arendt, Johannes Staguhn, Eli Dwek, Mark R. Morris, Farhad Yusef-Zadeh, Dominic J. Benford, Attila Kovács, Junellie Gonzalez-Quiles. 2019-09-17. 2 mm GISMO Observations of the Galactic Center. I. Dust Emission. https://doi.org/10.3847/1538-4357/ab451c

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