# The Early Data Release of the Dark Energy Spectroscopic Instrument

**Authors:** J. Aguilar, L. Jiang, A. Lambert, J. Silber, J. Yu, X. Fan, C. Zhao, Z. Zhou, S. Chen, B. Wang, W. Sheu, A. Dey, D. Lang, A. Meisner, J. Moustakas, A. D. Myers, E. F. Schlafly, A. Balaguera-Antolínez, F. J. Castander, A. S. Bolton  
**arXiv:** [2306.06308](https://arxiv.org/abs/2306.06308)  
**Date:** 2023-06-09  
**Summary page:** https://www.summarizepaper.com/en/paper/2306.06308v1/

## Key points

- The Dark Energy Spectroscopic Instrument (DESI) completed its Survey Validation (SV) phase in May 2021.
- The SV phase involved obtaining spectra of stellar and extragalactic targets, constituting the first major data sample from the DESI survey.
- The public release includes high-quality spectral information from various target classes:
- 466,447 objects from the Milky Way Survey
- 428,758 objects from the Bright Galaxy Survey
- 227,318 objects from the Luminous Red Galaxy sample
- 437,664 objects from the Emission Line Galaxy sample
- 76,079 objects from the Quasar sample
- Additional spectral data from 137,148 objects as part of secondary programs.
- Section 2 provides an overview of DESI instrument design and SV observations, including a summary of target classes.
- Section 3 focuses on spectral processing and data quality assessment methods used during SV.
- Section 4 discusses creation and utilization of large-scale structure (LSS) value-added catalogs accompanying this release.
- Section 5 describes online access to released data and tutorials for effective analysis.
- Section 6 concludes with a summary of results obtained using SV data and outlines plans for future releases.

## Summary

The Dark Energy Spectroscopic Instrument (DESI) recently completed its five-month Survey Validation (SV) in May 2021, marking a significant milestone for the project. The SV phase involved obtaining spectra of stellar and extragalactic targets, which constitute the first major data sample from the DESI survey. In this paper, the authors describe the public release of these spectra, along with catalogs of derived properties and intermediate data products. The public release includes high-quality spectral information from various target classes. Specifically, it comprises spectra from 466,447 objects targeted as part of the Milky Way Survey, 428,758 objects from the Bright Galaxy Survey, 227,318 objects from the Luminous Red Galaxy sample, 437,664 objects from the Emission Line Galaxy sample, and 76,079 objects from the Quasar sample. Additionally, there are spectral data from 137,148 objects that expand beyond the primary samples as part of secondary programs. In this paper's organization, Section 2 provides an overview of the DESI instrument design and SV observations. It also offers a summary of the target classes included in this data release. Detailed descriptions of these target classes can be found in Appendix A and Appendix B. Section 3 focuses on spectral processing and data quality assessment methods employed during SV. It discusses procedures used to process and analyze spectra included in this release as well as insights into data quality assessment methods employed during SV. Next, Section 4 delves into creation and utilization of large-scale structure (LSS) value-added catalogs accompanying this release. These catalogs pertain to One-Percent Survey offering valuable scientific insights into large-scale structures. Section 5 describes online access to released data outlining how researchers can access and retrieve specific datasets for their analyses along with tutorials with examples provided to assist users in working with these spectra effectively. Finally, Section 6 concludes with brief summary of results obtained using SV data and outlines plans for future releases highlighting significance of these results in advancing our understanding of dark energy and cosmological measurements. Overall this paper provides comprehensive overview of DESI SV data release offering detailed information on spectral data; data quality assessment; derived catalogs; access to data; references for further background information; setting stage for future analyses using DESI's vast spectroscopic sample.