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arXiv · 2311.16394

High-Resolution, Mid-Infrared Color Temperature Mapping of the Central 10 Arcseconds of the Galaxy

Cuc K. Dinh·Anna Cuirlo·Mark R. Morris·Rainer Schödel·Andrea Ghez·Tuan Do
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Abstract

The neighborhood of the Galactic black hole boasts a plethora of extended interstellar gas and dust features as well as populations of compact (unresolved, or marginally resolved) features such as the G objects. Most are well manifested in the infrared. To disentangle and characterize the infrared structure of extended features and identify compact sources, we used 3.8~$\mu$m (L' filter) data from the NIRC2 imager at the Keck Observatory and 8.6~$\mu$m (PAH1 filter) data from the VISIR imager at the Very Large Telescope (VLT) to produce the highest-resolution mid-IR color-temperature map of the inner half-parsec of the Galactic Center to date. From this map, we compile a catalog of features that stand out from their background. In particular, we identify 33 compact sources that stand out against the local background temperature, 11 of which are newly identified and are candidates for being members of the G objects population. Additionally, we resolve and newly characterize the morphology of several known extended features. These results prepare the way for ongoing and future JWST studies that have access to a greater range of mid-infrared wavelengths, and thus will allow for refined estimation of the trends of dust temperatures.

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Cuc K. Dinh, Anna Cuirlo, Mark R. Morris, Rainer Schödel, Andrea Ghez, Tuan Do. 2023-11-28. High-Resolution, Mid-Infrared Color Temperature Mapping of the Central 10 Arcseconds of the Galaxy. https://arxiv.org/abs/2311.16394

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