Dr. van Dokkum and his team will conduct a survey using the NEWFIRM infrared imager at NOAO's Kitt Peak 4-meter telescope to measure photometric redshifts of galaxies out to z=3.5. The innovative aspect is a set of medium-band filters that splits the J atmospheric window near 1.2 microns into three bands, and the H window near 1.6 microns into two bands. Simulations show that these finer bands should yield estimates of the redshift that are roughly four times more precise than those from broadband surveys, and with a tenfold smaller rate of 'catastrophic' failure where the predicted redshift is grossly discrepant. Telescope time has already been allocated for a survey of four fields each thirty arc minutes on a side, which should include 18,000 galaxies at redshifts above 1.5 that are bright enough to obtain reliable photometric redshifts. This study will obtain luminosity and mass functions of the red sequence galaxies at high redshift, and study their stellar populations, environment and clustering.
Two graduate students and a postdoc will participate in the research. The spectral energy distributions and redshifts for the survey galaxies will be released to the astronomical community, and the medium-band filters bought under this grant will be available for general use once the project is concluded. The team will produce a 3-D movie for a projector system at the new Yale Planetarium, to be built with private donations on the outskirts of the New Haven campus.
