Abstract
Abstract We present Atacama Large Millimeter/submillimeter Array Band 5 observations of a galaxy at z = 1.91, GDS24569, in search of molecular gas in its vicinity via the [C i] 3P1–3P0 line. GDS24569 is a massive ( ), passively evolving galaxy, characterized by compact morphology with an effective radius of ∼0.5 kpc. We apply two blind detection algorithms to the spectral data cubes and find no promising detection in or around GDS24569 out to a projected distance of ∼320 kpc, while a narrow tentative line (4.1σ) is identified at +1200 km s−1 by one of the algorithms. From the nondetection of [C i], we place a 3σ upper limit on molecular hydrogen mass, ∼ 7.1 × 109 M ⊙, which converts to an extremely low gas-to-stellar mass fraction of ≲ 5%. We conduct a spectral energy distribution modeling by including optical to far-infrared data and find a considerably high ( ∼ 0.1%) dust-to-stellar mass ratio, i.e., ∼10–100× higher than those of local early-type galaxies. In combination with a previous result of an insufficient number of surrounding satellite galaxies, it is suggested that GDS24569 is unlikely to experience significant size evolution via satellite mergers. We discuss possible physical mechanisms that quenched GDS24569.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.