Dye, S and Eales, S A and Gomez, H L and Jones, G C and Smith, M W L and Borsato, E and Moss, A and Dunne, L and Maresca, J and Amvrosiadis, A and Negrello, M and Marchetti, L and Corsini, E M and Ivison, R J and Bendo, G J and Bakx, T and Cooray, A and Cox, P and Dannerbauer, H and Serjeant, S and Riechers, D and Temi, P and Vlahakis, C (2022) 'A high-resolution investigation of the multiphase ISM in a galaxy during the first two billion years.', Monthly Notices of the Royal Astronomical Society, 510 (3). pp. 3734-3757.
We have carried out the first spatially resolved investigation of the multiphase interstellar medium (ISM) at high redshift, using the z = 4.24 strongly lensed submillimetre galaxy H-ATLASJ142413.9+022303 (ID141). We present high-resolution (down to ∼350 pc) ALMA observations in dust continuum emission and in the CO(7–6), H2O(21,1−20,2), [C I] (1–0), and [C I] (2–1) lines, the latter two allowing us to spatially resolve the cool phase of the ISM for the first time. Our modelling of the kinematics reveals that the system appears to be dominated by a rotationally-supported gas disc with evidence of a nearby perturber. We find that the [C I] (1–0) line has a very different distribution to the other lines, showing the existence of a reservoir of cool gas that might have been missed in studies of other galaxies. We have estimated the mass of the ISM using four different tracers, always obtaining an estimate in the range of 3.2−3.8×1011 M⊙, significantly higher than our dynamical mass estimate of 0.8−1.3×1011 M⊙. We suggest that this conflict and other similar conflicts reported in the literature is because the gas-to-tracer ratios are ≃4 times lower than the Galactic values used to calibrate the ISM in high-redshift galaxies. We demonstrate that this could result from a top-heavy initial mass function and strong chemical evolution. Using a variety of quantitative indicators, we show that, extreme though it is at z = 4.24, ID141 will likely join the population of quiescent galaxies that appears in the Universe at z ∼ 3.
|Full text:||(VoR) Version of Record|
Download PDF (4452Kb)
|Publisher Web site:||https://doi.org/10.1093/mnras/stab3569|
|Publisher statement:||This article has been accepted for publication in Monthly notices of the Royal Astronomical Society. ©: 2021 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.|
|Date accepted:||30 November 2021|
|Date deposited:||16 June 2022|
|Date of first online publication:||09 December 2021|
|Date first made open access:||16 June 2022|
Save or Share this output
|Look up in GoogleScholar|