Forming stars in a dual AGN host: molecular and ionized gas in the nearby, luminous infrared merger, Mrk 266. Issue 1 (22nd November 2022)

• Record Type: Journal Article
• Authors: Beaulieu, Damien; Petric, Andreea; Robert, Carmelle; Alatalo, Katherine; Heckman, Timothy; Merhi, Maya; Rousseau-Nepton, Laurie; Rowlands, Kate
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 518:Issue 1(2023)
• Page Start: 1407
• Page End: 1417
• Publication Date: 2022-11-22
• Subjects: galaxies: individual: NGC 5256 -- galaxies: interactions -- galaxies: nuclei -- galaxies: star formation; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stac3048
• Languages: English
• ISSNs: 0035-8711

Abstract

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 H2 mass in the central region of 1.1 ± 0.3 × 10 10 M⊙ which leads to a possible future star formation rate of 25 ± 10 M⊙ yr −1 . With the Fourier Transform Spectrograph (SITELLE) on the Canada–France–Hawaii Telescope, we measure an integrated H α luminosity and estimate a present-day star formation rate of 15 ± 2 M⊙ 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 active galactic nuclei but the two galaxy components differ: the region around the south-western nucleus appears to be more active than the north-east nucleus, which seems relatively quiet. We speculate that this difference may originate in the properties of the interstellar medium in the two systems.