Star formation and gas inflows in the OH megamaser galaxy IRAS03056+2034

Abstract

We have obtained observations of the OH Megamaser galaxy IRAS03056+0234 using Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (IFU), Very Large Array (VLA) and Hubble Space Telescope (HST). The HST data reveals spiral arms containing knots of emission associated to star forming regions. The GMOS-IFU data cover the spectral range of 4500 to 7500Å at a velocity resolution of 90 km s −1 and spatial resolution of 506 pc. The emission-line flux distributions reveal a ring of star forming regions with radius of 786 pc centred at the nucleus of the galaxy, with an ionized gas mass of 1.2× 10 8 M ⊙ , an ionizing photon luminosity of log Q[H + ]=53.8 and a star formation rate of 4.9 M ⊙ yr −1 . The emission-line ratios and radio emission suggest that the gas at the nuclear region is excited by both starburst activity and an active galactic nucleus. The gas velocity fields are partially reproduced by rotation in the galactic plane, but show, in addition, excess redshifts to the east of the nucleus, consistent with gas inflows towards the nucleus, with velocity of ∼45 km s −1 and a mass inflow rate of ∼7.7×10 −3 M ⊙ yr −1 .

The OH Megamaser galaxy IRAS11506−3851: an AGN and star formation revealed by multiwavelength observations

“…We also found knots of star formation in the nuclear region of the eastern galaxy of the pair and report a new OH Maser detection. In Hekatelyne et al (2018b), we used multiwavelength data to conclude that IRAS03056+2034 presents evidence of an embedded AGN and circumnuclear star formation that also contributes to the ionization of the gas. Finally, in Sales et al (2019), multiwavelength observations show that IRAS 17526+3253 presents two kinematic components and the emission-line ratio diagnostic diagrams indicate that young stars are the main source of ionization for both of them.…”

GOALS-JWST: Gas Dynamics and Excitation in NGC 7469 Revealed by NIRSpec

“…Evidence for this comes from the detection of outflows on a variety of physical scales and gas phases: cold (Feruglio et al 2010;Xu et al 2014;Veilleux et al 2017;Barcos-Muñoz et al 2018;Falstad et al 2018;Lutz et al 2020;Pereira-Santaella et al 2020) and hot molecular gas (U et al 2013Medling & Rich 2015;Riffel et al 2020;Motter et al 2021), as well as moderately (Rich et al 2012(Rich et al , 2014(Rich et al , 2015Arribas et al 2014;Robleto-Orús et al 2021;Xu & Wang 2022) and highly ionized gas (Rodríguez-Ardila et al 2006;Müller-Sánchez et al 2011;U et al 2022;Armus et al 2023) and neutral gas (Rupke & Veilleux 2011;Morganti et al 2016;Su et al 2023). Streaming motions, such as gas inflows, toward the nuclear regions of ULIRGs have also been detected in some sources (Hekatelyne et al 2018;Aalto et al 2019;Medling et al 2019;González-Alfonso et al 2021). These inflows may act in providing the fuel necessary to trigger and feed the AGN.…”

The OH Megamaser galaxy IRAS11506-3851: an AGN and starformation revealed by multiwavelength observations

“…We also found knots of star formation in the nuclear region of the eastern galaxy of the pair and report a new OH maser detection. In Hekatelyne et al (2018b) we used multi-wavelength data to conclude that IRAS03056+2034 presents evidence of an embedded AGN and circumnuclear star formation that also contributes to the ionization of the gas. Finally, in Sales et al (2019), multi-wavelength observations show that IRAS 17526+3253 presents two kinematic components and the emission-line ratio diagnostic diagrams indicate that young stars are the main source of ionization for both of them.…”