The search for failed supernovae with the Large Binocular Telescope: a new candidate and the failed SN fraction with 11 yr of data. Issue 1 (13th September 2021)

• Record Type: Journal Article
• Authors: Neustadt, J M M; Kochanek, C S; Stanek, K Z; Basinger, C; Jayasinghe, T; Garling, C T; Adams, S M; Gerke, J
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 508:Issue 1(2021)
• Page Start: 516
• Page End: 528
• Publication Date: 2021-09-13
• Subjects: black hole physics -- surveys -- stars: massive -- supernovae: general; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stab2605
• Languages: English
• ISSNs: 0035-8711

Abstract

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 (Δ L / L > 3) luminosity changes.