Data Release 1 of the Dark Energy Spectroscopic Instrument (2503.14745v1)

Abstract: In 2021 May the Dark Energy Spectroscopic Instrument (DESI) collaboration began a 5-year spectroscopic redshift survey to produce a detailed map of the evolving three-dimensional structure of the universe between $z=0$ and $z\approx4$. DESI's principle scientific objectives are to place precise constraints on the equation of state of dark energy, the gravitationally driven growth of large-scale structure, and the sum of the neutrino masses, and to explore the observational signatures of primordial inflation. We present DESI Data Release 1 (DR1), which consists of all data acquired during the first 13 months of the DESI main survey, as well as a uniform reprocessing of the DESI Survey Validation data which was previously made public in the DESI Early Data Release. The DR1 main survey includes high-confidence redshifts for 18.7M objects, of which 13.1M are spectroscopically classified as galaxies, 1.6M as quasars, and 4M as stars, making DR1 the largest sample of extragalactic redshifts ever assembled. We summarize the DR1 observations, the spectroscopic data-reduction pipeline and data products, large-scale structure catalogs, value-added catalogs, and describe how to access and interact with the data. In addition to fulfilling its core cosmological objectives with unprecedented precision, we expect DR1 to enable a wide range of transformational astrophysical studies and discoveries.

Overview of "Data Release 1 of the Dark Energy Spectroscopic Instrument" Paper

The paper "Data Release 1 of the Dark Energy Spectroscopic Instrument" outlines the release of the first data set from the Dark Energy Spectroscopic Instrument (DESI). DESI aims to map the universe's three-dimensional structure and enhance the understanding of dark energy, a critical component influencing cosmic acceleration. The first data release (DR1) consists of observations collected during the first 13 months of the DESI main survey, alongside reprocessed validation data.

Scientific Goals and Objectives

DESI's primary scientific objectives include:

1. Precise determination of the dark energy equation of state.
2. Measurement of the growth rate of large-scale structure influenced by gravity.
3. Constraint of the sum of neutrino masses.
4. Exploration of the observational imprints of primordial fluctuations that give rise to large-scale structure.

To achieve these goals, DESI employs a highly multiplexed instrument capable of acquiring spectra for up to 5,000 objects simultaneously with a wide spectral coverage, allowing measurements of Baryon Acoustic Oscillations and redshift space distortions across different epochs.

Data Overview

DR1 includes observations from 2021 May to 2022 June, and represents a significant resource for the astronomical community:

• It provides approximately 18.7 million redshifts, featuring 13.1 million galaxies, more than 1.6 million quasars, and 4 million stars.
• DESI achieved unprecedented coverage and depth, with a footprint spanning over 9,000 square degrees.
• The data allows for analyses of various astrophysical phenomena beyond its core cosmological science cases.

Instrumentation and Methodology

DESI's design and instrumentation facilitate efficient data acquisition under various observational conditions:

• It integrates 5,000 robotic fibers, each connected to a spectrograph with three-channel coverage spanning 3600–9800 Å, allowing precise redshift measurements necessary for large-scale cosmic mapping.
• The spectroscopic pipeline processes raw data through sky subtraction, wavelength calibration, and flux calibration, providing robust spectral classifications and redshift determinations.
• The Redrock software application plays a crucial role in classifying spectra into stars, galaxies, and quasars while estimating their respective redshifts.

Implications and Future Directions

The implications of DR1 extend beyond the immediate scientific goals of DESI:

• It complements existing and future cosmological surveys by providing rich datasets for cross-correlation studies.
• The vast redshift catalog fosters opportunities for novel investigations into galaxy formation and evolution, potentially spurring new theoretical models.
• As ongoing data releases continue to expand the accessible volume and completeness, refined measurements of cosmic expansion history and matter clustering will tighten constraints on fundamental cosmological parameters.

Further engagements anticipate advancements in machine learning for more precise data processing, and improved synergy with multi-messenger observational campaigns, fostering an integrated understanding of the cosmos.

In conclusion, DESI DR1 stands as a monumental leap forward in cosmic cartography, paving the way toward unprecedented precision in the exploration of the universe's anatomy, the nature of dark energy, and the potential of novel physical paradigms.