2004/08/13 by Tohru Nagao, T. Nagao, Y. Taniguchi +71
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #CCD and CMOS Imaging Sensors #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1086/424965
published as Astrophys.J. 613 (2004) L9-L12 · 13 pages including 3 figures, to appear in The Astrophysical Journal Letters
arxiv created 2004/08/13 · openalex publication_date 2004/08/23 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We report on the discovery of a star-forming galaxy at z = 6.33 in the Subaru Deep Field. This object is selected as a candidate of an i '-dropout high-redshift galaxy around z = 6 because of its red i ' - z ' color in our deep optical imaging survey in the Subaru Deep Field. Our follow-up optical spectroscopy reveals that this object is a strong Lyα emitter with only very faint ultraviolet continuum. The rest-frame equivalent width of the detected Lyα emission is as much as 130 Å. Thus the light detected in our z ' image is largely attributed to the Lyα emission, i.e., ~40% of the z '-band flux is the strong Lyα emission, giving a very red i ' - z ' color. This is consistent with the photometric property of this object because the narrowband data obtained with the NB921 filter show a significant depression, z ' - NB921 = -0.54 mag. By using the photometric data, we show that some other objects among the 48 i '-dropout high-redshift galaxy candidates found in the Subaru Deep Field also show a significant NB921 depression. We briefly discuss the nature of these NB921-depressed objects.