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Title: AT2023fhn (the Finch): a luminous fast blue optical transient at a large offset from its host galaxy
ABSTRACT

Luminous fast blue optical transients (LFBOTs) – the prototypical example being AT 2018cow – are a rare class of events whose origins are poorly understood. They are characterized by rapid evolution, featureless blue spectra at early times, and luminous X-ray and radio emission. LFBOTs thus far have been found exclusively at small projected offsets from star-forming host galaxies. We present Hubble Space Telescope, Gemini, Chandra, and Very Large Array observations of a new LFBOT, AT 2023fhn. The Hubble Space Telescope data reveal a large offset (>3.5 half-light radii) from the two closest galaxies, both at redshift z ∼ 0.24. The location of AT 2023fhn is in stark contrast with previous events, and demonstrates that LFBOTs can occur in a range of galactic environments.

 
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NSF-PAR ID:
10469107
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society: Letters
Volume:
527
Issue:
1
ISSN:
1745-3925
Format(s):
Medium: X Size: p. L47-L53
Size(s):
["p. L47-L53"]
Sponsoring Org:
National Science Foundation
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