ZEUS-2: a second generation submillimeter grating spectrometer for exploring distant galaxies

Abstract

ZEUS-2, the second generation (z)Redshift and Early Universe Spectrometer, like its predecessor is a moderate resolution (R~1000) long-slit, echelle grating spectrometer optimized for the detection of faint, broad lines from distant galaxies. It is designed for studying star-formation across cosmic time. ZEUS-2 employs three TES bolometer arrays (555 pixels total) to deliver simultaneous, multi-beam spectra in up to 4 submillimeter windows. The NIST Boulder-built arrays operate at ~100mK and are readout via SQUID multiplexers and the Multi-Channel Electronics from the University of British Columbia. The instrument is cooled via a pulse-tube cooler and two-stage ADR. Various filter configurations give ZEUS-2 access to 7 different telluric windows from 200 to 850 micron enabling the simultaneous mapping of lines from extended sources or the simultaneous detection of the 158 micron [CII] line and the [NII] 122 or 205 micron lines from z = 1-2 galaxies. ZEUS-2 is designed for use on the CSO, APEX and possibly JCMT.

Wideband Sub-mm Wave Superconducting Integrated Filter-bank Spectrometer

“…Once these astronomical objects have been mapped in the sky, the spectrometers can target them for spectral characterization. State of the Art spectrometers tackle the dispersion of light in two chief ways: using diffraction optics and waveguides [2][3][4] or using on-chip dispersion mechanisms like filter-banks [5][6][7] and 2D gratings [8]. The on-chip filter-bank solutions have a clear advantage in terms of scalability and compactness, which are key requirements for multi-pixel spectrometers.…”

Design and first-light performance of TES bolometer arrays for submillimeter spectroscopy with ZEUS-2

“…ZEUS-2 will continue and build upon this important and ground breaking work of understanding star formation across cosmic time by working towards three scientific goals , provides a detailed description of the ZEUS-2 science program 9 1. Investigate star formation in the early Universe by detecting redshifted far-IR fine-structure lines from distant (z > 0.25 -5, see Figure 2) galaxies.…”

A waveguide filter bank for millimeter-wave spectroscopy

“…Ground-based grating spectrometers such as Z-Spec [1], which covers the 1 mm atmospheric window with R~300, and ZEUS-2 [2], which covers seven windows from 200-850 μm with R~1000, represent the state of the art for long-wavelength spectroscopy, but both instruments are large and bulky due to their reliance on optical interference to create spectra, thus limiting them to a single spatial pixel. Recently, there have been efforts to develop an ultra-compact filter bank spectrometer (e.g.…”