Deep Submillimeter Observations of Two Lyα-emitting Galaxies at z ~ 6.5
Abstract
We present deep submillimeter imaging of two spectroscopically confirmed z~6.5 Lyα emitters (LAEs) in the Subaru Deep Field. Although we reach the nominal confusion limit at 850 μm, neither LAE is detected at 850 or 450 μm thus, we conclude that the LAEs do not contain large dust masses (<2.3×108 and <5.7×108 Msolar). The limit on their average LFIR/LUV ratios (<~35) is substantially lower than seen for most submillimeter-selected galaxies at z~3 and is within the range of values exhibited by Lyman break galaxies. We place upper limits on their individual star formation rates of <~248 and <~613 Msolar yr-1, and on the cosmic star formation rate density of the z~6.5 LAE population of <~5.0×10-2 Msolar yr-1 Mpc-3. In the two submillimeter pointings, we also serendipitously detect seven sources at 850 μm that we estimate to lie at 1<z<5.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2007
- DOI:
- 10.1086/510061
- arXiv:
- arXiv:astro-ph/0609613
- Bibcode:
- 2007ApJ...659...76W
- Keywords:
-
- Galaxies: Formation;
- Galaxies: High-Redshift;
- Galaxies: Starburst;
- Submillimeter;
- Astrophysics
- E-Print:
- Accepted for publication by ApJ