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arXiv · 2210.10853

Forming Stars in a Dual AGN Host: Molecular and Ionized Gas in the Nearby, Luminous Infrared Merger, Mrk 266

Damien Beaulieu·Andreea Petric·Carmelle Robert·Katherine Alatalo·Timothy Heckman·Maya Merhi·Laurie Rousseau-Nepton·Kate Rowlands
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Abstract

We present star formation rates based on cold and ionized gas measurements of Mrk 266 (NGC 5256), a system composed of two colliding gas-rich galaxies, each hosting an active galactic nucleus. Using $^{12}$CO (1-0) observations with the Combined Array for Research in Millimeter-Wave Astronomy (CARMA), we find a total H$_2$ mass in the central region of $1.1\pm0.3\times10^{10}$ $M_\odot$ which leads to a possible future star formation rate of $25\pm10 M_\odot$ yr$^{-1}$. With the Fourier Transform Spectrograph (SITELLE) on the Canada-France-Hawaii Telescope, we measure an integrated H$\alpha$ luminosity and estimate a present-day star formation rate of $15\pm2 M_\odot$ yr$^{-1}$ in the core of the system (avoiding the two active nuclei). These results confirm that Mrk 266 is an intermediate stage merger with a relatively high recent star formation rate and enough molecular gas to sustain it for a few hundred million years. Inflowing gas associated with the merger may have triggered both the starburst episode and two AGN but the two galaxy components differ: the region around the SW nucleus appears to be more active than the NE nucleus, which seems relatively quiet. We speculate that this difference may originate in the properties of the interstellar medium in the two systems.

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Damien Beaulieu, Andreea Petric, Carmelle Robert, Katherine Alatalo, Timothy Heckman, Maya Merhi, Laurie Rousseau-Nepton, Kate Rowlands. 2022-10-19. Forming Stars in a Dual AGN Host: Molecular and Ionized Gas in the Nearby, Luminous Infrared Merger, Mrk 266. https://doi.org/10.1093/mnras/stac3048

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