MUSE Spectroscopic Identifications of Ultra-faint Emission Line Galaxies with M UV ∼ -15
Abstract
Using an ultra-deep blind survey with the MUSE integral field spectrograph on the European Southern Observatory Very Large Telescope, we obtain spectroscopic redshifts to a depth never before explored: galaxies with observed magnitudes m AB ≳ 30-32. Specifically, we detect objects via Lyα emission at 2.9 < z < 6.7 without individual continuum counterparts in areas covered by the deepest optical/near-infrared imaging taken by the Hubble Space Telescope, the Hubble Ultra Deep Field. In total, we find 102 such objects in 9 square arcminutes at these redshifts. Detailed stacking analyses confirm the Lyα emission as well as the 1216 Å breaks and faint ultraviolet continua (M UV ∼ -15). This makes them the faintest spectroscopically confirmed objects at these redshifts, similar to the sources believed to reionize the universe. A simple model for the expected fraction of detected/undetected Lyα emitters as a function of luminosity is consistent with these objects being the high-equivalent width tail of the normal Lyα-emitter population at these redshifts.
Based on observations made with ESO telescopes at the La Silla Paranal Observatory under program IDs 094.A-2089(B), 095.A-0010(A), 096.A-0045(A), and 096.A-0045(B); and based on data obtained with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2018
- DOI:
- 10.3847/2041-8213/aade4b
- arXiv:
- arXiv:1809.01142
- Bibcode:
- 2018ApJ...865L...1M
- Keywords:
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- galaxies: evolution;
- galaxies: high-redshift;
- quasars: emission lines;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 7 pages, 4 figures, 1 table