A Search for Failed Supernovae and Other Observational Constraints on the Supernova Mechanism

Ohio State University, The, Columbus OH

Investigators

Abstract

The goal of this project is to better understand the final fates of massive stars. At the end of their lives, all stars more than roughly ten times the mass of our Sun build an iron core which collapses from the size of the Earth to the size of a city once its mass exceeds a critical limit. In many cases this results in an luminous, supernova explosion, but there is increasing evidence that this is not the only outcome. This work will (a) discover or set useful constraints on the fraction of massive stars that produce a black hole without a supernova explosion; (b) clarify the boundary between the least luminous supernova explosions and the variability of massive stars that does not lead a supernova explosion; and (c) measure the properties of these stars just before their deaths, including pioneering studies of their variability. The project will advance our scientific understanding of these massive stars while training the next generation of scientists. The research steps for a better understanding of the fates of massive stars include using unique, multifaceted observational and theoretical approaches. The centerpiece is a project using the twin 8.4m Large Binocular Telescope to monitor all the massive evolved stars in 27 nearby star-forming galaxies. The primary goals are to: (1) Discover or set interesting constraining limits on the fraction of core collapses that fail, producing a black hole without a supernova explosion; (2) Measure the properties of SN progenitors while pioneering studies of their variability and binarity; (3) Explore the boundary between the faintest SN and stellar outbursts, in particular by better understanding the nature of the SN "impostors" and the SN2008S class of dusty transients. While doing so, the project will advance the training of students and post-docs and broaden the public's understanding and interest in science, aided by their fascination with stars and their complicated roads to death.