Large telescope project dedicated to an origins survey

We describe an "Origins Survey" that will provide a comprehensive picture of the era of galaxy formation and assembly. The survey data will allow us to develop and test models of when and how the first condensed objects in the universe are formed. We propose to do this by accumulating enough redshifts to have 10,000 galaxies of each of 20 types (defined empirically by the real state of galaxies) in each of 10 time zones of duration 1.5 Gyr each. Discounting the first two such zones which will be covered by the SDSS, the 2DF, and other surveys, our plan is to obtain redshifts for a total of 2 million galaxies. The hardware design is driven by the requirement to see the earliest galaxies (z ∼ 10) and the capability to carry out this high z survey in an elapsed time of five years on a dedicated telescope. These considerations lead to a tentative design that uses a 20-40 meter diameter telescope with an Integral Field Unit (IFU) high-resolution spectrograph (R=6000) operating in the 1-2.5 micron spectral range. We require a 1-3 arc minute field of view with a modest adaptive-optics-corrected 0.2 arc-sec half power diameter point spread function (in the near-IR). Simultaneous, complementary observations will be made in the far-infrared/submm (350-850) microns to view the "hidden" starbursts known to exist from SCUBA data and the (non-CMB) infrared background. These observations require a low water vapor site. With appropriate instrumentation the same telescope can be used to study proto-planetary disks and star formation regions in the low z Universe. In this paper we present the scientific case for the survey, the basis for our requirements, and the results of our preliminary studies of how best to meet these goals.