Evidence for cold accretion onto a massive galaxy at high redshift?
Abstract
In this Letter we report on the discovery of a z = 2.83 Lyman α Blob (LAB) found in our wide-field narrow-band survey within the Spitzer First Look Survey region. The blob is extended over at least 95 kpc and has a total Lyman α luminosity of 2.1 × 1044 erg s-1. It is only the sixth LAB known of this scale (>50 kpc), and is associated with an embedded continuum source in g', R, i', K and 4.5-μm bands. The LAB's optical spectrum shows clumpy structures and tantalising hints of a sharp red cut-off and shear within the Lyman α emission line. Studies of the LAB's surface brightness profile and of the continuum counterpart's spectral energy distribution indicate that the profuse Lyman α emission is consistent with being powered by cold gas accreting onto a massive dark matter halo.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- June 2007
- DOI:
- 10.1111/j.1745-3933.2007.00318.x
- arXiv:
- arXiv:astro-ph/0703522
- Bibcode:
- 2007MNRAS.378L..49S
- Keywords:
-
- galaxies: formation;
- galaxies: haloes;
- galaxies: high-redshift;
- Astrophysics
- E-Print:
- 6 pages, 4 figures, accepted by MNRAS. Replacement to match published version