THE NEWFIRM MEDIUM-BAND SURVEY: PHOTOMETRIC CATALOGS, REDSHIFTS, AND THE BIMODAL COLOR DISTRIBUTION OF GALAXIES OUT TO<i>z</i>∼ 3

We present deep near-IR (NIR) medium-bandwidth photometry over the wavelength range 1–1.8μm in the All-wavelength Extended Groth strip International Survey (AEGIS) and Cosmic Evolution Survey (COSMOS) fields. The observations were carried out using the NOAO Extremely Wide-Field Infrared Imager (NEWFIRM) on the Mayall 4 m Telescope on Kitt Peak as part of the NEWFIRM Medium-Band Survey (NMBS), an NOAO survey program. In this paper, we describe the full details of the observations, data reduction, and photometry for the survey. We also present a public K-selected photometric catalog, along with accurate photometric redshifts. The redshifts are computed with 37 (20) filters in the COSMOS (AEGIS) fields, combining the NIR medium-bandwidth data with existing UV (&lt;i&gt;Galaxy Evolution Explorer&lt;/i&gt;), visible and NIR (Canada–France–Hawaii Telescope and Subaru Telescope), and mid-IR (&lt;i&gt;Spitzer&lt;/i&gt;/IRAC) imaging.We find excellent agreement with publicly available spectroscopic redshifts, with σz/(1 + z) ~ 1%–2% for ~4000 galaxies at z = 0–3. The NMBS catalogs contain ~13,000 galaxies at z &gt; 1.5 with accurate photometric redshifts and rest-frame colors. Due to the increased spectral resolution obtained with the five NIR medium-band filters, the median 68% confidence intervals of the photometric redshifts of both quiescent and star-forming galaxies are a factor of about two times smaller when comparing catalogs with medium-band NIR photometry to NIR broadband photometry. We show evidence for a clear bimodal color distribution between quiescent and star-forming galaxies that persists to z ~ 3, a higher redshift than has been probed so far.

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