The HETDEX Instrumentation: Hobby–Eberly Telescope Wide-field Upgrade and VIRUS
Abstract

The Hobby–Eberly Telescope (HET) Dark Energy Experiment (HETDEX) is undertaking a blind wide-field low-resolution spectroscopic survey of 540 deg2of sky to identify and derive redshifts for a million Lyα-emitting galaxies in the redshift range 1.9 <z< 3.5. The ultimate goal is to measure the expansion rate of the universe at this epoch, to sharply constrain cosmological parameters and thus the nature of dark energy. A major multiyear Wide-Field Upgrade (WFU) of the HET was completed in 2016 that substantially increased the field of view to 22′ diameter and the pupil to 10 m, by replacing the optical corrector, tracker, and Prime Focus Instrument Package and by developing a new telescope control system. The new, wide-field HET now feeds the Visible Integral-field Replicable Unit Spectrograph (VIRUS), a new low-resolution integral-field spectrograph (LRS2), and the Habitable Zone Planet Finder, a precision near-infrared radial velocity spectrograph. VIRUS consists of 156 identical spectrographs fed by almost 35,000 fibers in 78 integral-field units arrayed at the focus of the upgraded HET. VIRUS operates in a bandpass of 3500−5500 Å with resolving powerR≃ 800. VIRUS is the first example of large-scale replication applied to instrumentation in optical astronomy to achieve spectroscopic surveys of very large more »

Authors:
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Publication Date:
NSF-PAR ID:
10362891
Journal Name:
The Astronomical Journal
Volume:
162
Issue:
6
Page Range or eLocation-ID:
Article No. 298
ISSN:
0004-6256
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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2. Abstract

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