Seminar - Jiayin Dong (Penn State) and Adam Jermyn (Flatiron/CCA)

Date: 

Monday, September 20, 2021, 11:00am to 12:00pm

Location: 

Zoom

" Tracing Dynamical History of TESS Warm Jupiters"

Warm Jupiters are a key missing piece in our understanding of how planetary systems form and evolve. It is currently debated whether Warm Jupiters form in situ or undergo disk or high eccentricity tidal migration. Using the Transiting Exoplanet Survey Satellite (TESS), we discover and characterize Warm Jupiters to trace their dynamical histories. I will first introduce two scientifically intriguing TESS Warm Jupiter systems that suggest very different dynamical pathways. I will then present a catalog of validated Warm Jupiters from a magnitude-limited search in the Year 1 of TESS Full-Frame Images and show their eccentricity distribution. Advances on both individual system studies and population statistics will greatly promote our understanding of Warm Jupiters.

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" Stellar Evolution in AGN Disks"

Active Galactic Nuclei (AGN) are powered by accretion disks surrounding a central supermassive black hole. Stars can both form in and be captured by these disks. Gas from the disk can accrete onto embedded stars, while also changing the usual stellar atmospheric boundary conditions. Here I describe some of the unusual kinds of stellar evolution of stars embedded in AGN disks (AGN stars). Under a wide range of circumstances AGN stars become very massive, reach the Eddington limit, pollute the disk with metals, and evolve into compact remnants. They also typically evolve into a rapidly rotating state, potentially generating Gamma Ray Bursts and rapidly rotating black holes.

See also: Seminars, 2021-22