The HETDEX Pilot Survey. I. Survey Design, Performance, and Catalog of Emission-Line Galaxies

Access full-text files




Adams, Joshua J.
Blanc, Guillermo A.
Hill, Gary J.
Gebhardt, Karl
Drory, Niv
Hao, Lei
Bender, Ralf
Byun, Joyce
Ciardullo, Robin
Cornell, Mark E.

Journal Title

Journal ISSN

Volume Title



We present a catalog of emission-line galaxies selected solely by their emission-line fluxes using awide-field integral field spectrograph. This work is partially motivated as a pilot survey for the upcoming Hobby-Eberly Telescope Dark Energy Experiment. We describe the observations, reductions, detections, redshift classifications, line fluxes, and counterpart inFormation for 397 emission-line galaxies detected over 169 square' with a 3500-5800 angstrom bandpass under 5 angstrom full-width-half-maximum (FWHM) spectral resolution. The survey's best sensitivity for unresolved objects under photometric conditions is between 4 and 20 x 10(-17) erg s(-1) cm(-2) depending on the wavelength, and Ly alpha luminosities between 3 x 10(42) and 6 x 10(42) erg s(-1) are detectable. This survey method complements narrowband and color-selection techniques in the search of high-redshift galaxies with its different selection properties and large volume probed. The four survey fields within the COSMOS, GOODS-N, MUNICS, and XMM-LSS areas are rich with existing, complementary data. We find 105 galaxies via their high-redshift Lya emission at 1.9 < z < 3.8, and the majority of the remainder objects are low-redshift [O II] 3727 emitters at z < 0.56. The classification between low-and high-redshift objects depends on rest-frame equivalent width (EW), as well as other indicators, where available. Based on matches to X-ray catalogs, the active galactic nuclei fraction among the Ly alpha emitters is 6%. We also analyze the survey's completeness and contamination properties through simulations. We find five high-z, highly significant, resolved objects with FWHM sizes >44 square '' which appear to be extended Ly alpha nebulae. We also find three high-z objects with rest-frame Ly alpha EW above the level believed to be achievable with normal star Formation, EW0 > 240 angstrom. Future papers will investigate the physical properties of this sample.


LCSH Subject Headings


Adams, Joshua J., Guillermo A. Blanc, Gary J. Hill, Karl Gebhardt, Niv Drory, Lei Hao, Ralf Bender et al. "The HETDEX Pilot Survey. I. Survey Design, Performance, and Catalog of Emission-line Galaxies." The Astrophysical Journal Supplement Series, Vol. 192, No. 1 (Jan., 2011): 5.