IngentaConnect An upper limit to Cii emission in a z 5 galaxy

Authors: Marsden, Gaelen; Borys, Colin¹; Chapman, Scott C.¹; Halpern, Mark²; Scott, Douglas²

Source: Monthly Notices of the Royal Astronomical Society, Volume 359, Number 1, May 2005 , pp. 43-46(4)

Abstract:

Low-ionization-state far-infrared (FIR) emission lines may be useful diagnostics of star formation activity in young galaxies, and at high redshift may be detectable from the ground. In practice, however, very little is known concerning how strong such line emission might be in the early Universe. We attempted to detect the 158-μm [C ii] line from a lensed galaxy at z= 4.926 using the Caltech Submillimeter Observatory. This source is an ordinary galaxy, in the sense that it shows high but not extreme star formation, but lensing makes it visible. Our analysis includes a careful consideration of the calibrations and weighting of the individual scans. We find only a modest improvement over the simpler reduction methods, however, and the final spectrum remains dominated by systematic baseline ripple effects. We obtain a 95 per cent confidence upper limit of 33 mJy for a 200 km s⁻¹ full width at half maximum line, corresponding to an unlensed luminosity of 1 × 10⁹ L_⊙ for a standard cosmology. Combining this with a marginal detection of the continuum emission using the James Clerk Maxwell Telescope, we derive an upper limit of 0.4 per cent for the ratio of L_[C II]/L_FIR in this object.

Keywords: galaxies: evolution; galaxies: formation; galaxies: high-redshift; cosmology: observations; submillimetre

Document Type: Research article

DOI: 10.1111/j.1365-2966.2005.08837.x

Affiliations: 1: California Institute of Technology, 1201 East California Blvd, Pasadena CA, 91125, USA 2: Department of Physics & Astronomy, University of British Columbia, 6224 Agricultural Rd, Vancouver BC, V6T 1Z1, Canada

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$50.39 plus tax Refund Policy

An upper limit to [C ii] emission in a z≃ 5 galaxy