ZEUS: the redshift (z) and early universe spectrometer

The redshift (z) and Early Universe Spectrometer (ZEUS) is an echelle grating spectrometer designed to study the history of star formation in the Universe from about 2 billion years after the Big Bang to the present by observing submillimeter and far-infrared spectral lines from distant dusty galaxies. ZEUS has moderate resolving power (R~1000), and large spectral coverage so as to optimize extragalactic point source sensitivity in the telluric submillimeter (350, 450, and 610 um) windows. When completed, ZEUS will have a 4 x 64-element array of TES PUD bolometers delivering an instantaneous 64-element spectrum for each of 4 spatial positions on the sky. ZEUS is designed for use on the 15 m JCMT telescope on Mauna Kea. We also plan to use it on the 12 m APEX telescope at the Chajnantor site in northern Chile. Our scientific goals include (1) investigating star formation in the early Universe by measuring the redshifted fine-structure lines from distant (z ~1 to 4) (proto-) galaxies, (2) measuring the redshifts of optically obscured submillimeter galaxies by detecting their bright 158 um [CII] line emission, and (3) investigating the properties of starburst and ultraluminous galaxies in the local Universe by observing their [CI] and mid-J CO rotational line emission.