THE UV LUMINOSITY FUNCTION OF STAR-FORMING GALAXIES VIA DROPOUT SELECTION AT REDSHIFTS z {approx} 7 AND 8 FROM THE 2012 ULTRA DEEP FIELD CAMPAIGN

Journal Article · Fri May 10 00:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/768/2/196· OSTI ID:22126701

Schenker, Matthew A.; Ellis, Richard S. ^[1]; Robertson, Brant E.; Schneider, Evan ^[2]; Ono, Yoshiaki; Ouchi, Masami; Stark, Daniel P. ^[3]; McLure, Ross J.; Dunlop, James S.; Bowler, Rebecca A. A.; Curtis-Lake, Emma; Rogers, Alexander B.; Cirasuolo, Michele ^[4]; Koekemoer, Anton ^[5]; Charlot, Stephane ^[6]

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1. Department of Astrophysics, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States)
2. Department of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)
3. Institute for Cosmic Ray Research, University of Tokyo, Kashiwa City, Chiba 277-8582 (Japan)
4. Institute for Astronomy, University of Edinburgh, Edinburgh EH9 3HJ (United Kingdom)
5. Space Telescope Science Institute, Baltimore, MD 21218 (United States)
6. UPMC-CNRS, UMR7095, Institut d'Astrophysique de Paris, F-75014 Paris (France)

We present a catalog of high-redshift star-forming galaxies selected to lie within the redshift range z {approx_equal} 7-8 using the Ultra Deep Field 2012 (UDF12), the deepest near-infrared (near-IR) exposures yet taken with the Hubble Space Telescope (HST). As a result of the increased near-IR exposure time compared to previous HST imaging in this field, we probe {approx}0.65 (0.25) mag fainter in absolute UV magnitude, at z {approx} 7 (8), which increases confidence in a measurement of the faint end slope of the galaxy luminosity function. Through a 0.7 mag deeper limit in the key F105W filter that encompasses or lies just longward of the Lyman break, we also achieve a much-refined color-color selection that balances high redshift completeness and a low expected contamination fraction. We improve the number of dropout-selected UDF sources to 47 at z {approx} 7 and 27 at z {approx} 8. Incorporating brighter archival and ground-based samples, we measure the z {approx_equal} 7 UV luminosity function to an absolute magnitude limit of M{sub UV} = -17 and find a faint end Schechter slope of {alpha}=-1.87{sup +0.18}{sub -0.17}. Using a similar color-color selection at z {approx_equal} 8 that takes our newly added imaging in the F140W filter into account, and incorporating archival data from the HIPPIES and BoRG campaigns, we provide a robust estimate of the faint end slope at z {approx_equal} 8, {alpha}=-1.94{sup +0.21}{sub -0.24}. We briefly discuss our results in the context of earlier work and that derived using the same UDF12 data but with an independent photometric redshift technique.

• OSTI ID: 22126701
• Journal Information: Astrophysical Journal, Vol. 768, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BALANCES
CATALOGS
EVOLUTION
FILTERS
GALAXIES
LUMINOSITY
PROBES
RED SHIFT
SPACE
STARS
TELESCOPES