The Bolocam Lockman Hole Millimeter-Wave Galaxy Survey: Galaxy Candidates and Number Counts

We present results of a new deep 1.1 mm survey using Bolocam, a millimeterwavelength bolometer array camera designed for mapping large fields at fast scan rates, without chopping. A map, galaxy candidate list, and derived number counts are presented. This survey encompasses 324 arcmin to an rms noise level (filtered for point sources) of σ1.1mm ≃ 1.4 mJy beam and includes the entire regions surveyed by the published 8 mJy 850 μm JCMT SCUBA and 1.2 mm IRAM MAMBO surveys. We reduced the data using a custom software pipeline to remove correlated sky and instrument noise via a principal component analysis. Extensive simulations and jackknife tests were performed to confirm the robustness of our source candidates and estimate the effects of false detections, bias, and completeness. In total, 17 source candidates were detected at a significance ≥ 3.0 σ, with six expected false detections. Nine candidates are new detections, while eight candidates have coincident SCUBA 850 μm and/or MAMBO 1.2 mm detections. From our observed number counts, we estimate the underlying differential number count distribution of submillimeter galaxies and find it to be in general agreement with previous surveys. Modeling the spectral energy distributions of these submillimeter galaxies after observations of dusty nearby galaxies suggests extreme luminosities of L = (1.0 − 1.6) × 10 L⊙ and, if powered by star formation, star formation rates of 500− 800 M⊙yr. Subject headings: galaxies: high-redshift — galaxies: starburst — submillimeter Center for Astrophysics and Space Astronomy & Department of Astrophysical and Planetary Sciences, University of Colorado, 593 UCB, Boulder, CO 80309-0593 Physics and Astronomy, Cardiff University, 5 The Parade, P.O. Box 913, Cardiff CF24 3YB, Wales, UK Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 California Institute of Technology, 1200 E. California Boulevard, MC 59-33, Pasadena, CA 91125 [email protected]