MODELING OF THE HERMES SUBMILLIMETER SOURCE LENSED BY A DARK MATTER DOMINATED FOREGROUND GROUP OF GALAXIES
- Institut d'Astrophysique de Paris, UMR 7095, CNRS, UPMC Univ. Paris 06, F-75014 Paris (France)
- Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)
- Department of Astrophysical and Planetary Sciences, CASA 389-UCB, University of Colorado, Boulder, CO 80309 (United States)
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States)
- NASA Ames Research Center, MS 245-6, Bldg. 245, Moffett Field, CA 94035 (United States)
- Cardiff School of Physics and Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff CF24 3AA (United Kingdom)
- Institut d'Astrophysique Spatiale (IAS), Universite Paris-Sud 11 and CNRS (UMR 8617), 91405 Orsay (France)
- Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States)
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
- Space Science Building, Cornell University, Ithaca, NY 14853-6801 (United States)
- Laboratoire d'Astrophysique de Marseille, OAMP, Universite Aix-Marseille, CNRS, 13388 Marseille cedex 13 (France)
- Laboratoire AIM-Paris-Saclay, CEA/DSM/Irfu-CNRS-Universite Paris Diderot, CEA-Saclay, F-91191 Gif-sur-Yvette (France)
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada)
- Department of Astrophysics, Denys Wilkinson Building, University of Oxford, Oxford OX1 3RH (United Kingdom)
- Astrophysics Group, Imperial College London, Blackett Laboratory, London SW7 2AZ (United Kingdom)
- Institut de RadioAstronomie Millimetrique, Domaine Universitaire, 38406 Saint Martin d'Heres (France)
We present the results of a gravitational lensing analysis of the bright z{sub s} = 2.957 submillimeter galaxy (SMG) HERMES found in the Herschel/SPIRE science demonstration phase data from the Herschel Multi-tiered Extragalactic Survey (HerMES) project. The high-resolution imaging available in optical and near-IR channels, along with CO emission obtained with the Plateau de Bure Interferometer, allows us to precisely estimate the intrinsic source extension and hence estimate the total lensing magnification to be {mu} = 10.9 {+-} 0.7. We measure the half-light radius R{sub eff} of the source in the rest-frame near-UV and V bands that characterize the unobscured light coming from stars and find R{sub eff,*} = [2.0 {+-} 0.1] kpc, in good agreement with recent studies on the SMG population. This lens model is also used to estimate the size of the gas distribution (R{sub eff,gas} = [1.1 {+-} 0.5] kpc) by mapping back in the source plane the CO (J = 5 {yields} 4) transition line emission. The lens modeling yields a relatively large Einstein radius R{sub Ein} = 4.''10 {+-} 0.''02, corresponding to a deflector velocity dispersion of [483 {+-} 16] km s{sup -1}. This shows that HERMES is lensed by a galaxy group-size dark matter halo at redshift z{sub l} {approx} 0.6. The projected dark matter contribution largely dominates the mass budget within the Einstein radius with f{sub dm}(< R{sub Ein}) {approx} 80%. This fraction reduces to f{sub dm}(< R{sub eff,G1} {approx_equal} 4.5 kpc) {approx} 47% within the effective radius of the main deflecting galaxy of stellar mass M{sub *,G1} = [8.5 {+-} 1.6] x 10{sup 11} M{sub sun}. At this smaller scale the dark matter fraction is consistent with results already found for massive lensing ellipticals at z {approx} 0.2 from the Sloan Lens ACS Survey.
- OSTI ID:
- 21584899
- Journal Information:
- Astrophysical Journal, Vol. 738, Issue 2; Other Information: DOI: 10.1088/0004-637X/738/2/125; Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Gravitational lens models based on submillimeter array imaging of Herschel -selected strongly lensed sub-millimeter galaxies at z > 1.5
3C 220.3: A radio galaxy lensing a submillimeter galaxy