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Title: The Active Galactic Nuclei in the Hobby–Eberly Telescope Dark Energy Experiment Survey (HETDEX). II. Luminosity Function

We present the Lyαemission line luminosity function (LF) of the active galactic nuclei (AGN) in the first release of the Hobby–Eberly Telescope Dark Energy Experiment Survey (HETDEX) AGN catalog. The AGN are selected either by emission line pairs characteristic of AGN or by a single broad emission line, free of any photometric preselections (magnitude/color/morphology). The sample consists of 2346 AGN spanning 1.88 <z< 3.53, covering an effective area of 30.61 deg2. Approximately 2.6% of the HETDEX AGN are not detected at >5σconfidence atr∼ 26 in the deepestr-band images we have searched. The Lyαline luminosity ranges from ∼1042.3to 1045.9erg s−1. Our LyαLF shows a turnover luminosity with opposite slopes on the bright end and the faint end: The space density is highest atLLyα=1043.4erg s−1. We explore the evolution of the AGN LF over a broader redshift range (0.8 <z< 3); constructing the rest-frame ultraviolet (UV) LF with the 1450 Å monochromatic luminosity of the power-law component of the continuum (M1450) fromM1450∼ −18 to −27.5. We divide the sample into three redshift bins (z∼ 1.5, 2.1, and 2.6). In all three redshift bins, our UV LFs indicate that the space density of AGN is highest at the more » turnover luminosityM1450*with opposite slopes on the bright end and the faint end. TheM1450LFs in the three redshift bins can be well fit with a luminosity evolution and density evolution model: the turnover luminosity (M1450*) increases, and the turnover density (Φ*) decreases with increasing redshift.

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Publication Date:
Journal Name:
The Astrophysical Journal
Page Range or eLocation-ID:
Article No. 132
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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