Yale Astronomy & Astrophysics Colloquium - Tyrone Woods

Event time: 
Thursday, April 9, 2020 - 2:30pm
Speaker: 
Tyrone Woods, Plaskett Fellow National Research Council
Speaker Institution: 
Herzberg Astronomy and Astrophysics Research Centre, Victoria BC
Talk Title: 
Titans of the Early Universe: The origin of the most massive, high-redshift quasars
Event description: 

The discovery of billion solar mass quasars at redshifts of 6–7 challenges our understanding of the early Universe; how did such massive objects form in the first billion years? Observational constraints and numerical simulations increasingly favour the “direct collapse” scenario. In this case, an atomically-cooled halo of primordial composition accretes rapidly onto a single protostellar core, ultimately collapsing through the Chandrasekhar-Feynman instability to produce a supermassive (~100,000 solar mass) “seed” black hole. In this talk, I’ll present a systematic study of the lives and deaths of these objects, including post-Newtonian corrections to gravity and a detailed treatment of nuclear burning processes using an adaptive network. We find a simple relation between the infall rate and the final mass at collapse, rule out the existence of rapidly-rotating supermassive stars, and delineate the regimes for which objects either undergo “truly direct” collapse or survive to long-lived nuclear-burning under differing formation scenarios. I’ll also discuss the possibility of early chemical enrichment from these objects, observational prospects in the era of the JWST, and briefly summarize other future directions.

Location: 
Watson Center A-51 See map
60 Sachem Street
New Haven, CT 06511
Open to: 
General Public
Admission: 
Free