Presentation #241.20 in the session Evolution of Galaxies — iPoster Session.
We present an overview and first results from the Gemini FENIKS survey. These include the identification and characterization of the photometric properties of extreme emission line galaxies (EELGs) and massive (log (M/M☉ > 10.5) galaxies at z > 3. FENIKS is a Gemini-South Large and Long Program that uses deep imaging from the Flamingos-2 near-IR camera with novel medium-band filters, a K-blue (λc=2.0 μm) and a K-red filter (λc=2.3 μm), both Δλ=0.26 μm wide with resolution, λ/Δλ~ 8-9. These filters “split” the K-band and are sensitive both to the Balmer/4000 Å breaks of galaxies at z > 4 and to galaxies with very strong emission lines (e.g., Hβ+[OIII], [OII]) at 3 < z < 6. We show that the new filters enable us to reduce photo-z uncertainties and contamination from star forming galaxies at lower redshift to < 3% for galaxies at 3 < z < 6. To date, FENIKS has probed nearly 900 arcmin2 split between the COSMOS and UDS extragalactic fields to depths of ~24 AB mag. We also report results from a recent Keck/MOSFIRE spectroscopic follow-up of FENIKS targets. The MOSFIRE data include deep spectra of 11 massive galaxies at z > 3 (including spectroscopic confirmations of quiescent candidates at z > 4) and 18 EELGs with indications of high [OIII] equivalent widths (>300 Å in the rest-frame at z=3-3.6). The MOSFIRE spectroscopy demonstrates the utility of the novel K-blue and K-red filters to identify the intended populations.