The Search for Failed Supernovae with the Large Binocular Telescope: Constraints from 7 Years of Data

TL;DR

This study uses 7 years of data from the Large Binocular Telescope to search for failed supernovae in nearby galaxies, finding a potential failure rate that explains missing high-mass progenitors and black hole mass distribution.

Contribution

First long-term observational constraints on failed supernovae fraction using LBT data, providing upper limits and implications for stellar evolution models.

Findings

Estimated failed supernova fraction is approximately 14% with large uncertainties.

No new failed supernova candidates identified in 7 years of data.

Failed supernovae could account for missing high-mass red supergiant progenitors.

Abstract

We report updated results for the first 7 years of our program to monitor 27 galaxies within 10 Mpc using the Large Binocular Telescope to search for failed supernovae (SNe) -- core-collapses of massive stars that form black holes without luminous supernovae. In the new data, we identify no new compelling candidates and confirm the existing candidate. Given the 6 successful core-collapse SNe in the sample and one likely failed SN, the implied fraction of core-collapses that result in failed SNe is $f = 0.14^{+0.33}_{-0.10}$ at 90% confidence. If the current candidate is a failed SN, the fraction of failed SN naturally explains the missing high-mass red supergiant SN progenitors and the black hole mass function. If the current candidate is ultimately rejected, the data implies a 90% confidence upper limit on the failed SN fraction of $f < 0.35$.