A CENSUS OF STAR-FORMING GALAXIES AT z = 1-3 IN THE SUBARU DEEP FIELD

Journal Article · Sun Jul 10 04:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/735/2/91· OSTI ID:21578405

Ly, Chun; Malkan, Matthew A ^[1]; Hayashi, Masao; Shimasaku, Kazuhiro ^[2]; Motohara, Kentaro ^[3]; Kashikawa, Nobunari ^[4]; Nagao, Tohru ^[5]; Grady, Celestine ^[6]

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1. Department of Physics and Astronomy, UCLA, Box 951547, Los Angeles, CA (United States)
2. Department of Astronomy, School of Science, University of Tokyo, Bunkyo, Tokyo (Japan)
3. Institute of Astronomy, University of Tokyo, Mitaka, Tokyo (Japan)
4. Optical and Infrared Astronomy Division, National Astronomical Observatory, Mitaka, Tokyo (Japan)
5. The Hakubi Project, Kyoto University, Kyoto (Japan)
6. Department of Applied Science, UC Davis, Davis, CA (United States)

Several UV and near-infrared color selection methods have identified galaxies at z = 1-3. Since each method suffers from selection biases, we have simultaneously applied three leading techniques (Lyman break, BX/BM, and BzK selection) in the Subaru Deep Field. This field has reliable ({Delta}z/(1 + z) = 0.02-0.09) photometric redshifts for {approx}53,000 galaxies from 20 bands (1500 A-2.2 {mu}m). The BzK, LBG, and BX/BM samples suffer contamination from z < 1 interlopers of 6%, 8%, and 20%, respectively. Around the redshifts where it is most sensitive (z {approx} 1.9 for star-forming BzK, z {approx} 1.8 for z {approx} 2 LBGs, z {approx} 1.6 for BM, and z {approx} 2.3 for BX), each technique finds 60%-80% of the census of the three methods. In addition, each of the color techniques shares 75%-96% of its galaxies with another method, which is consistent with previous studies that adopt identical criteria on magnitudes and colors. Combining the three samples gives a comprehensive census that includes {approx}90% of z{sub phot} = 1-3 galaxies, using standard magnitude limits similar to previous studies. In fact, we find that among z = 1-2.5 galaxies in the color selection census, 81%-90% of them can be selected by just combining the BzK selection with one of the UV techniques (z {approx} 2 LBG or BX and BM). The average galaxy stellar mass, reddening, and star formation rates (SFRs) all decrease systematically from the sBzK population to the LBGs, and to the BX/BMs. The combined color selections yield a total cosmic SFR density of 0.18 {+-} 0.03 M{sub sun} yr{sup -1} Mpc{sup -3} for K{sub AB} {approx}< 24. We find that 65% of the star formation is in galaxies with E(B - V) > 0.25 mag, even though they are only one-fourth of the census by number.

• OSTI ID: 21578405
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 735; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ELECTROMAGNETIC RADIATION
EVOLUTION
GALACTIC EVOLUTION
GALAXIES
INFRARED RADIATION
PHOTOMETRY
RADIATIONS
RED SHIFT
STARS
ULTRAVIOLET RADIATION