Performance of the Dark Energy Spectroscopic Instrument(DESI) Fiber System

TL;DR

This paper discusses the development, deployment, and lessons learned from the fiber system of the DESI instrument, which is designed to measure the universe's expansion through spectroscopic observations of millions of galaxies.

Contribution

It provides a detailed account of the design, implementation, and operational experience of the fiber system for DESI, a major astronomical survey instrument.

Findings

Successful deployment of 5000 fiber positioners

Efficient data collection from 35 million galaxies and quasars

Key lessons for future fiber system designs

Abstract

The recently commissioned Dark Energy Spectroscopic Instrument (DESI) will measure the expansion historyof the universe using the Baryon Acoustic Oscillation technique. The spectra of 35 million galaxies and quasarsover 14000 sq deg will be measured during the life of the experiment. A new prime focus corrector for theKPNO Mayall telescope delivers light to 5000 fiber optic positioners. The fibers in turn feed ten broad-bandspectrographs. We describe key aspects and lessons learned from the development, delivery and installation ofthe fiber system at the Mayall telescope.