English

Improved Redshifts for DESI EDR Quasars

Astrophysics of Galaxies 2023-08-31 v1 Cosmology and Nongalactic Astrophysics

Abstract

The Dark Energy Spectroscopic Instrument (DESI) survey will provide optical spectra for 3\sim 3 million quasars. Accurate redshifts for these quasars will facilitate a broad range of science applications. Here we provide improved systemic redshift estimates for the 95\sim 95k quasars included in the DESI Early Data Release (EDR), based on emission-line fits to the quasar spectra. The majority of the DESI pipeline redshifts are reliable. However, 19%\sim 19\% of the EDR quasars have pipeline redshifts that deviate from our new redshifts by >500kms1>500\,{\rm km\,s^{-1}}. We use composite quasar spectra to demonstrate the improvement of our redshift estimates, particularly at z>1z>1. These new redshifts are available at \url{https://github.com/QiaoyaWu/DESI_EDR_qsofit/blob/main/DESI_EDR_Aug29_redshift_only.fits}.

Keywords

Cite

@article{arxiv.2308.15586,
  title  = {Improved Redshifts for DESI EDR Quasars},
  author = {Qiaoya Wu and Yue Shen},
  journal= {arXiv preprint arXiv:2308.15586},
  year   = {2023}
}

Comments

3 pages, 1 figure. Submitted to RNAAS, comments welcome!