A Detailed Gravitational Lens Model Based on Submillimeter Array and Keck Adaptive Optics Imaging of a Herschel-ATLAS Sub-millimeter Galaxy at z=4.243

Дата и время публикации : 2012-07-11T17:55:55Z

Авторы публикации и институты :
R. S. Bussmann
M. A. Gurwell
Hai Fu
D. J. B. Smith
S. Dye
R. Auld
M. Baes
A. J. Baker
D. Bonfield
A. Cava
D. L. Clements
A. Cooray
K. Coppin
H. Dannerbauer
A. Dariush
G. De Zotti
L. Dunne
S. Eales
J. Fritz
R. Hopwood
E. Ibar
R. J. Ivison
M. J. Jarvis
S. Kim
L. L. Leeuw
S. Maddox
M. J. Michalowski
M. Negrello
E. Pascale
M. Pohlen
D. A. Riechers
E. Rigby
Douglas Scott
P. Temi
P. P. Van der Werf
A. Verma
J. Wardlow
D. Wilner

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: Accepted to the ApJ. 12 pages, 6 figures, 3 tables
Первичная категория: astro-ph.CO

Все категории : astro-ph.CO, astro-ph.GA

Краткий обзор статьи: We present high-spatial resolution imaging obtained with the Submillimeter Array (SMA) at 880um and the Keck Adaptive Optics (AO) system at Ks-band of a gravitationally lensed sub-millimeter galaxy (SMG) at z=4.243 discovered in the Herschel-Astrophysical Terahertz Large Area Survey. The SMA data (angular resolution ~0.6") resolve the dust emission into multiple lensed images, while the Keck AO Ks-band data (angular resolution ~0.1") resolve the lens into a pair of galaxies separated by 0.3". We present an optical spectrum of the foreground lens obtained with the Gemini-South telescope that provides a lens redshift of z_lens = 0.595 +/- 0.005. We develop and apply a new lens modeling technique in the visibility plane that shows that the SMG is magnified by a factor of mu = 4.1 +/- 0.2 and has an intrinsic infrared (IR) luminosity of L_IR = (2.1 +/- 0.2) x 10^13 Lsun. We measure a half-light radius of the background source of r_s = 4.4 +/- 0.5 kpc which implies an IR luminosity surface density of Sigma_IR = (3.4 +/- 0.9) x 10^11 Lsun kpc^-2, a value that is typical of z > 2 SMGs but significantly lower than IR luminous galaxies at z~0. The two lens galaxies are compact (r_lens ~ 0.9 kpc) early-types with Einstein radii of theta_E1 = 0.57 +/- 0.01 and theta_E2 = 0.40 +/- 0.01 that imply masses of M_lens1 = (7.4 +/- 0.5) x 10^10 Msun and M_lens2 = (3.7 +/- 0.3) x 10^10 Msun. The two lensing galaxies are likely about to undergo a dissipationless merger, and the mass and size of the resultant system should be similar to other early-type galaxies at z~0.6. This work highlights the importance of high spatial resolution imaging in developing models of strongly lensed galaxies discovered by Herschel.

Category: Physics