Revealing the complex nature of the strong gravitationally lensed system H-ATLAS J090311.6+003906 using ALMA - Archive ouverte HAL Access content directly
Journal Articles Monthly Notices of the Royal Astronomical Society Year : 2015

Revealing the complex nature of the strong gravitationally lensed system H-ATLAS J090311.6+003906 using ALMA

, , , , , , , , , , , , , (1) , ,
1
S. Dye
  • Function : Author
C. Furlanetto
  • Function : Author
A. M. Swinbank
  • Function : Author
C. Vlahakis
  • Function : Author
J. W. Nightingale
  • Function : Author
L. Dunne
  • Function : Author
S. A. Eales
  • Function : Author
Ian Smail
I. Oteo
  • Function : Author
T. Hunter
  • Function : Author
M. Negrello
  • Function : Author
H. Dannerbauer
  • Function : Author
R. J. Ivison
  • Function : Author
A. Cooray
  • Function : Author
P. van Der Werf
  • Function : Author

Abstract

We have modelled Atacama Large Millimetre/sub-millimetre Array (ALMA) long baseline imaging of the strong gravitational lens system H-ATLAS J090311.6+003906 (SDP.81). We have reconstructed the distribution of band 6 and 7 continuum emission in the z = 3.042 source and determined its kinematic properties by reconstructing CO(5-4) and CO(8-7) line emission in bands 4 and 6. The continuum imaging reveals a highly non-uniform distribution of dust with clumps on scales of ∼200 pc. In contrast, the CO line emission shows a relatively smooth, disc-like velocity field which is well fitted by a rotating disc model with an inclination angle of (40 ± 5)° and an asymptotic rotation velocity of 320 km s-1. The inferred dynamical mass within 1.5 kpc is (3.5 ± 0.5) × 1010 M which is comparable to the total molecular gas masses of (2.7 ± 0.5) × 1010 M and (3.5 ± 0.6) × 1010 M from the dust continuum emission and CO emission, respectively. Our new reconstruction of the lensed Hubble Space Telescope near-infrared emission shows two objects which appear to be interacting, with the rotating disc of gas and dust revealed by ALMA distinctly offset from the near-infrared emission. The clumpy nature of the dust and a low value of the Toomre parameter of Q ∼ 0.3 suggest that the disc is in a state of collapse. We estimate a star formation rate in the disc of 470 ± 80 M yr-1 with an efficiency ∼65 times greater than typical low-redshift galaxies. Our findings add to the growing body of evidence that the most infrared luminous, dust obscured galaxies in the high-redshift Universe represent a population of merger-induced starbursts.
Fichier principal
Vignette du fichier
stv1442.pdf (4.36 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

insu-03644863 , version 1 (28-04-2022)

Identifiers

Cite

S. Dye, C. Furlanetto, A. M. Swinbank, C. Vlahakis, J. W. Nightingale, et al.. Revealing the complex nature of the strong gravitationally lensed system H-ATLAS J090311.6+003906 using ALMA. Monthly Notices of the Royal Astronomical Society, 2015, 452, pp.2258-2268. ⟨10.1093/mnras/stv1442⟩. ⟨insu-03644863⟩
11 View
2 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More