Gravitationally lensed radio emission associated with SMM J16359+6612, a multiply imaged submillimeter galaxy behind A2218

Abstract

We report the detection of discrete, lensed radio emission from the multiply imaged, z=2.516 submillimetre selected galaxy, SMM J16359+6612. All three images are detected in deep WSRT 1.4 GHz and VLA 8.2 GHz observations, and the radio positions are coincident with previous sub-mm SCUBA observations of this system. This is the widest separation lens system to be detected in the radio so far, and the first time that multiply imaged lensed radio emission has been detected from a star forming galaxy -- all previous multiply-lensed radio systems being associated with radio-loud AGN. Taking into account the total magnification of ~45, the WSRT 1.4 GHz observations suggest a star formation rate of 500 Solar mass/yr. The source has a steep radio spectrum (alpha -0.7) and an intrinsic flux density of just 3 microJy at 8.2 GHz. Three other SCUBA sources in the field are also detected by the WSRT, including SMMJ16359+66118, a singly imaged (and magnified) arclet at z=1.034. Higher resolution radio observations of SMMJ16359+6612 (and other highly magnified star forming galaxies) provide a unique opportunity to study the general properties and radio morphology of intrinsically faint, distant and obscured star forming galaxies. They can also help to constrain the technical specification of next generation radio telescopes, such as the Square Kilometre Array.

5 pages, 2 figures, to appear in A&A letters

References in corpus (5)

• The FIR/Radio correlation of high redshift galaxies in the HDF-N
• Multiply-imaged submm galaxy in a z~2.5 group
• Locating the starburst in the SCUBA galaxy, SMM J14011+0252
• Detection of CO from SMM J16359+6612, The Multiply Imaged Submillimeter Galaxy Behind A2218
• Galaxies Under the Cosmic Microscope: A GMOS Study of the Lensed Disk-Galaxy #289 in A2218

Cited by in corpus (14)

• The SCUBA HAlf Degree Extragalactic Survey (SHADES) - III. Identification of radio and mid-infrared counterparts to submillimetre galaxies
• Probing the submillimetre number counts at f(850um) < 2mJy
• Physical properties and morphology of a newly identified compact z=4.04 lensed submillimeter galaxy in Abell 2218
• An ultradeep submillimetre map: beneath the SCUBA confusion limit with lensing and robust source extraction
• ALMA Lensing Cluster Survey: an ALMA galaxy signposting a MUSE galaxy group at z=4.3 behind 'El Gordo'
• The discovery of lensed radio and X-ray sources behind the Frontier Fields cluster MACS J0717.5+3745 with the JVLA and Chandra
• The faintest radio source yet: EVLA observations of the gravitational lens SDSS J1004+4112
• Measuring space-time variation of the fundamental constants with redshifted submillimetre transitions of neutral carbon
• Highly-magnified, Multiply-imaged radio counterparts of the Sub-mm Starburst Emission in the Cluster-Lens MS0451.6-0305
• Astrophysics in 2005
• Very Large Array observations of the 8 o'clock arc lens system: Radio emission and a limit on the star-formation rate
• An EVLA search for water megamaser emission in the submm galaxy SMM J16359+6612 at z=2.5
• Strong gravitational lensing with upcoming wide-field radio surveys
• The final candidate from the JVAS/CLASS search for 6 arcsec to 15 arcsec image separation lensing