When:
Tuesday, April 6, 2021
4:00 PM - 5:00 PM CT
Where: Online
Audience: Faculty/Staff - Student - Post Docs/Docs - Graduate Students
Contact:
Samantha Westlake
Group: Physics and Astronomy Astrophysics Seminars
Category: Academic
Abstract: Half of the heaviest elements in the periodic table are synthesized in the rapid neutron-capture process (r-process), but the astrophysical origin of these elements has been debated for over 60 years. The current debate centers around whether r-process elements are mostly synthesized by neutron star mergers or rare core-collapse supernovae. The recent observation of a neutron star merger in both gravitational waves and electromagnetic radiation (GW170817 and its associated gamma ray burst/kilonova) did not resolve this debate, but it does emphasize the close connection between elemental abundances of stars and direct observations of astrophysical transients. In this talk, I will show two examples of how chemical abundances in old, metal-poor stars can be combined with observations of astrophysical transients to understand r-process nucleosynthesis. First, I will use abundance ratios in metal-poor stars to predict the expected composition of future kilonovae. Second, I will use long gamma ray bursts to motivate a new model for explaining r-process scatter in metal-poor stars. These examples highlight the promise of connecting stellar abundances and astrophysical transients, but I will also discuss the crucial role of early galaxy formation in making this connection.
Speaker: Alexander Ji, The University of Chicago
Website: https://www.alexji.com/
Host: Wen-fai Fong
If you know someone who would be interested in attending this talk, please contact Samantha Westlake (samantha.westlake@northwestern.edu) to access the Zoom link.
Keywords: Physics, Astronomy, Astrophysics