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Title: The search for failed supernovae with the Large Binocular Telescope: a new candidate and the failed SN fraction with 11 yr of data
ABSTRACT We present updated results of the Large Binocular Telescope Search for Failed Supernovae. This search monitors luminous stars in 27 nearby galaxies with a current baseline of 11 yr of data. We re-discover the failed supernova (SN) candidate N6946-BH1 as well as a new candidate, M101-OC1. M101-OC1 is a blue supergiant that rapidly disappears in optical wavelengths with no evidence for significant obscuration by warm dust. While we consider other options, a good explanation for the fading of M101-OC1 is a failed SN, but follow-up observations are needed to confirm this. Assuming only one clearly detected failed SN, we find a failed SN fraction $f = 0.16^{+0.23}_{-0.12}$ at 90 per cent confidence. We also report on a collection of stars that show slow (∼decade), large amplitude (ΔL/L > 3) luminosity changes.
Authors:
; ; ; ; ; ; ;
Award ID(s):
1814440
Publication Date:
NSF-PAR ID:
10348501
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
508
Issue:
1
Page Range or eLocation-ID:
516 to 528
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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