The DESI survey validation: results from visual inspection of bright galaxies, luminous red galaxies, and emission line galaxies

Ting-Wen Lan*, R. Tojeiro, E. Armengaud, J. Xavier Prochaska, T. M. Davis, David M. Alexander, A. Raichoor, Rongpu Zhou, Christophe Yeche, C. Balland, S. BenZvi, A. Berti, R. Canning, A. Carr, H. Chittenden, S. Cole, M.-C. Cousinou, K. Dawson, Biprateep Dey, K. DouglassA. Edge, S. Escoffier, A. Glanville, S. Gontcho A Gontcho, J. Guy, C. Hahn, C. Howlett, Ho Seong Hwang, L. Jiang, A. Kovacs, M. Mezcua, S. Moore, S. Nadathur, M. Oh, D. Parkinson, A. Rocher, A. J. Ross, V. Ruhlmann-Kleider, C. G. Sabiu, K. Said, C. Saulder, D. Sierra-Porta, B. Weiner, J. Yu, P. Zarrouk, Y. Zhang, H. Zou, S. Ahlen, S. Bailey, D. Brooks, A. P. Cooper, A. de la Macorra, A. Dey, G. Dhungana, P. Doel, S. Eftekharzadeh, K. Fanning, A. Font-Ribera, L. Garrison, E. Gaztanaga, R. Kehoe, T. Kisner, A. Kremin, M. Landriau, L. Le Guillou, Michael E. Levi, C. Magneville, Aaron M. Meisner, R. Miquel, J. Moustakas, Adam D. Myers, Jeffrey A. Newman, J. D. Nie, N. Palanque-Delabrouille, W. J. Percival, C. Poppett, F. Prada, M. Schubnell, Gregory Tarle, B. A. Weaver, K. Zhang, Zhimin Zhou

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

29 Citations (Scopus)
4 Downloads (Pure)

Abstract

The Dark Energy Spectroscopic Instrument (DESI) Survey has obtained a set of spectroscopic measurements of galaxies for validating the final survey design and target selections. To assist these tasks, we visually inspect (VI) DESI spectra of approximately 2,500 bright galaxies, 3,500 luminous red galaxies, and 10,000 emission line galaxies, to obtain robust redshift identifications. We then utilize the VI redshift information to characterize the performance of the DESI operation. Based on the VI catalogs, our results show that the final survey design yields samples of bright galaxies, luminous red galaxies, and emission line galaxies with purity greater than 99%. Moreover, we demonstrate that the precision of the redshift measurements is approximately 10 km/s for bright galaxies and emission line galaxies and approximately 40 km/s for luminous red galaxies. The average redshift accuracy is within 10 km/s for the three types of galaxies. The VI process also helps to improve the quality of the DESI data by identifying spurious spectral features introduced by the pipeline. Finally, we show examples of unexpected real astronomical objects, such as Lyman α emitters and strong lensing candidates, identified by VI. These results demonstrate the importance and utility of visually inspecting data from incoming and upcoming surveys, especially during their early operation phases.
Original languageEnglish
Article number68
Number of pages18
JournalAstrophysical Journal
Volume943
Issue number1
DOIs
Publication statusPublished - 25 Jan 2023

Keywords

  • Catalogs
  • Surveys
  • Cosmology: observations
  • Galaxies: general

Fingerprint

Dive into the research topics of 'The DESI survey validation: results from visual inspection of bright galaxies, luminous red galaxies, and emission line galaxies'. Together they form a unique fingerprint.

Cite this