English

On the recent discovery claim of a new $z>7$ quasar

Astrophysics of Galaxies 2023-04-13 v2 Earth and Planetary Astrophysics Instrumentation and Methods for Astrophysics

Abstract

Koptelova et al. 2022 (K22) recently claimed a new quasar discovery at z=7.46z=7.46. After careful consideration of the publicly-available data underlying K22's claim, we find that the observations were contaminated by a moving Solar System object, likely a main-belt asteroid. In the absence of the contaminated photometry, there is no evidence for the nearby, persistent WISE source being a high-redshift object; in fact, a detection of the source in DELS zz-band rules out a redshift z>7.3z>7.3. We present our findings as a cautionary tale of the dangers of passing asteroids for photometric selections.

Keywords

Cite

@article{arxiv.2304.05162,
  title  = {On the recent discovery claim of a new $z>7$ quasar},
  author = {Sarah E. I. Bosman and Frederick B. Davies and Eduardo Bañados},
  journal= {arXiv preprint arXiv:2304.05162},
  year   = {2023}
}

Comments

RNAAS; 2 pages, 1 figure. The asteroid has been conclusively identified as (43838) 1993 FW49