Taking the Measure of the Universe with Stellar Explosions

Type Ia supernovae (SNe Ia) are superb distance indicators and are used to map the expansion history of the Universe. Two decades ago, astronomers used observations of SNe Ia to find that the Universe's expansion is currently accelerating. Since this initial discovery, we have used SNe Ia to constrain the nature of "dark energy," which drives this accelerated expansion. To improve our dark energy constraints beyond our current basic understanding, we must design new and better SN surveys as well as improve our understanding of the physics of the SN explosion itself. I will show how high-cadence Kepler telescope light curves have provided us with crucial insight into the progenitor channels and physics of SN explosions. With light echoes of historic SNe, we can investigate the cause (the explosion/eruption) and the effect (the remnant) of the same astronomical event, even allowing us to look at the same event from different directions. I will also present the Foundation Supernova survey, a new high-fidelity, low-redshift (z < 0.1) survey I started in 2015 that will replace the current heterogenous low-redshift sample and reduce the (currently) largest uncertainties for SN cosmology. I will discuss the next major leap in SN cosmology, pushing to high-redshift and NIR with JWST and WFIRST. With the combination of the Foundation survey, the next generation of space-based observatories, and new physical understanding, SNe Ia will remain a premier cosmological probe, continuing the legacy started decades earlier.

Date: 
12 Sep 2017
Time: 
4:00PM
Location: 
215 Sharp Lab
Speaker: 
Armin Rest, STScI
Host: 
Gizis