Herschel *-ATLAS: deep HST/WFC3 imaging of strongly lensed submillimetre galaxies

Author(s)

Mattia Negrello, Rosalind Hopwood, Simon Dye, Helmut Dannerbauer

Abstract

We report on deep near-infrared observations obtained with the Wide Field Camera-3 (WFC3) onboard the Hubble Space Telescope (HST) of the first five confirmed gravitational lensing events discovered by the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). We succeed in disentangling the background galaxy from the lens to gain separate photometry of the two components. The HST data allow us to significantly improve on previous constraints of the mass in stars of the lensed galaxy and to perform accurate lens modelling of these systems, as described in the accompanying paper by Dye et al. We fit the spectral energy distributions of the background sources from near-IR to millimetre wavelengths and use the magnification factors estimated by Dye et al. to derive the intrinsic properties of the lensed galaxies. We find these galaxies to have star-formations rates (SFR) ~ 400-2000 M

_⊙ yr

^-1, with ~(6-25) × 10

¹⁰ M

_⊙ of their baryonic mass already turned into stars. At these rates of star formation, all remaining molecular gas will be exhausted in less than ~100 Myr, reaching a final mass in stars of a few 10

¹¹ M

_⊙. These galaxies are thus proto-ellipticals caught during their major episode of star formation, and observed at the peak epoch (z ~ 1.5-3) of the cosmic star formation history of the Universe.

Organisation(s)

Department of Astrophysics

External organisation(s)

Open University, University of Nottingham

Journal

Monthly Notices of the Royal Astronomical Society

Volume

440

Pages

1999-2012

No. of pages

14

ISSN

0035-8711

DOI

https://doi.org/10.1093/mnras/stu413

Publication date

05-2014

Peer reviewed

Yes

Austrian Fields of Science 2012

103003 Astronomy, 103004 Astrophysics

Keywords

ASJC Scopus subject areas

Astronomy and Astrophysics, Space and Planetary Science

Portal url

https://ucrisportal.univie.ac.at/en/publications/885dfc8d-b29a-430a-a20a-58966e2af7e9