THE EVOLUTION OF Ly{alpha}-EMITTING GALAXIES BETWEEN z = 2.1 AND z = 3.1

Journal Article · Tue Jan 10 04:00:00 EST 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/744/2/110· OSTI ID:22004259

Ciardullo, Robin; Gronwall, Caryl; Wolf, Christopher; McCathran, Emily; Matkovic, Ana ^[1]; others, and

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1. Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

We describe the results of a new, wide-field survey for z = 3.1 Ly{alpha} emitters (LAEs) in the Extended Chandra Deep Field South (ECDF-S). By using a nearly top-hat 5010 A filter and complementary broadband photometry from the MUSYC survey, we identify a complete sample of 141 objects with monochromatic fluxes brighter than 2.4 Multiplication-Sign 10{sup -17} erg cm{sup -2} s{sup -1} and observers-frame equivalent widths (EWs) greater than {approx}80 A (i.e., 20 A in the rest frame of Ly{alpha}). The bright end of this data set is dominated by X-ray sources and foreground objects with Galaxy Evolution Explorer detections, but when these interlopers are removed, we are still left with a sample of 130 LAE candidates, 39 of which have spectroscopic confirmations. This sample overlaps the set of objects found in an earlier ECDF-S survey, but due to our filter's redder bandpass, it also includes 68 previously uncataloged sources. We confirm earlier measurements of the z = 3.1 LAE emission-line luminosity function and show that an apparent anticorrelation between EW and continuum brightness is likely due to the effect of correlated errors in our heteroskedastic data set. Finally, we compare the properties of z = 3.1 LAEs to LAEs found at z = 2.1. We show that in the {approx}1 Gyr after z {approx} 3, the LAE luminosity function evolved significantly, with L* fading by {approx}0.4 mag, the number density of sources with L > 1.5 Multiplication-Sign 10{sup 42} erg s{sup -1} declining by {approx}50%, and the EW scale length contracting from 70{sup +7}{sub -5} A to 50{sup +9}{sub -6} A. When combined with literature results, our observations demonstrate that over the redshift range z {approx} 0 to z {approx} 4, LAEs contain less than {approx}10% of the star formation rate density of the universe.

• OSTI ID: 22004259
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 744; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BRIGHTNESS
COSMIC X-RAY SOURCES
COSMOLOGY
GALACTIC EVOLUTION
GALAXIES
LUMINOSITY
MONOCHROMATIC RADIATION
PHOTOMETRY
RED SHIFT
STARS
UNIVERSE