The discovery of a z = 0.7092 oh megamaser with the mightee survey
No Thumbnail Available
Date
2024
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Oxford University Press
Abstract
We present the discovery of the most distant OH megamaser (OHM) to be observed in the main lines, using data from the MeerKAT International Giga-Hertz Tiered Extragalactic Exploration (MIGHTEE) survey. At a newly measured redshift of z = 0.7092, the system has strong emission in both the 1665 MHz (L ≈ 2500 L-) and 1667 MHz (L ≈ 4.5 × 104 L-) transitions, with both narrow and broad components. We interpret the broad line as a high-velocity-dispersion component of the 1667 MHz transition, with velocity v ∼330 km s-1 with respect to the systemic velocity. The host galaxy has a stellar mass of M = 2.95 × 1010 M- and a star formation rate of SFR = 371 M- yr-1, placing it ∼1.5 dex above the main sequence for star-forming galaxies at this redshift, and can be classified as an ultraluminous infrared galaxy. Alongside the optical imaging data, which exhibit evidence for a tidal tail, this suggests that the OHM arises from a system that is currently undergoing a merger, which is stimulating star formation and providing the necessary conditions for pumping the OH molecule to saturation
Description
Keywords
galaxies: ISM, galaxies: starburst, ISM: molecules, masers
Citation
Jarvis, M.J., Heywood, I., Jewell, S.M., Deane, R.P., Klöckner, H.R., Ponomareva, A.A., Maddox, N., Baker, A.J., Bianchetti, A., Hess, K.M. and Roberts, H., 2024. The discovery of az= 0.7092 OH megamaser with the MIGHTEE survey. Monthly Notices of the Royal Astronomical Society, 529(4), pp.3484-3494.