Overview of the Instrumentation for the Dark Energy Spectroscopic Instrument

By B. Abareshi, J. Aguilar, S. Ahlen, Shadab Alam, D. M. Alexander, R. Alfarsy, L. Allen, C. Allende Prieto, O. Alves, J.Ameel and 257 more. Astronomical Journal, 2022

365 citations recorded by the source corpus.

The Dark Energy Spectroscopic Instrument (DESI) embarked on an ambitious 5 yr survey in 2021 May to explore the nature of dark energy with spectroscopic measurements of 40 million galaxies and quasars. DESI will determine precise redshifts and employ the baryon acoustic oscillation method to measure distances from the nearby universe to beyond redshift z > 3.5, and employ redshift space distortions to measure the growth of structure and probe potential modifications to general relativity. We describe the significant instrumentation we developed to conduct the DESI survey. This includes: a wide-field, 3.°2 diameter prime-focus corrector; a focal plane system with 5020 fiber positioners on the 0.812 m diameter, aspheric focal surface; 10 continuous, high-efficiency fiber cable bundles that connect the focal plane to the spectrographs; and 10 identical spectrographs. Each spectrograph employs a pair of dichroics to split the light into three channels that together record the light from 360–980 nm with a spectral resolution that ranges from 2000–5000. We describe the science requirements, their connection to the technical requirements, the management of the project, and interfaces between subsystems. DESI was installed at the 4 m Mayall Telescope at Kitt Peak National Observatory and has achieved all of its performance goals. Some performance highlights include an rms positioner accuracy of better than 0.″1 and a median signal-to-noise ratio of 7 of the [O ii] doublet at 8 × 10−17 erg s−1 cm−2 in 1000 s for galaxies at z = 1.4–1.6. We conclude with additional highlights from the on-sky validation and commissioning, key successes, and lessons learned.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/224c0f5e56c2d51dbb69ac31423ad0c353e2a8d5

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Citations in the corpus

Data Release 1 of the Dark Energy Spectroscopic Instrument (2025, neutral): “Table 2 summarizes some of the other key parameters of the instrument; additional details can be found in DESI Collaboration et al. ( 2022 ) and J. Guy et al. ( 2023 ) .”
The Optical Corrector for the Dark Energy Spectroscopic Instrument (2023, background): “The ADC movement time within the exposure sequence is described in more detail in Abareshi et al. (2022).”
Target Selection and Validation of DESI Quasars (2022, background): “The Dark Energy Spectroscopic Instrument (DESI; Levi et al. 2013; DESI Collaboration et al. 2016a, 2016b; Abareshi et al. 2022) survey will measure with high precision the baryon acoustic feature imprinted on the large-scale structure of the universe, as well as the distortions of galaxy clustering…”
Target Selection and Validation of DESI Emission Line Galaxies (2022, methodology): “Indeed, a DESI requirement that played an important role in the instrumental design was that this limit should be 10, 9, 9, 8, and 9× 10−17 erg s−1cm−2 in the redshift bins 0.6–0.8, 0.8–1.0, 1.0–1.2, 1.2–1.4, and 1.4–1.6, for nominal ELG observations (see Table 5 of Abareshi et al. 2022).”
The Spectroscopic Data Processing Pipeline for the Dark Energy Spectroscopic Instrument (2022, methodology): “Standard exposure sequence The standard exposure sequence is described in detail in Abareshi et al. (2022).”