Oct 21, 2021

Keivan Stassun, Vanderbilt University

"“Star Formation, Solar Physics, and Stellar Astrophysics: A Data-Intensive Approach” This will be a ZOOM talk."

Large time-domain surveys, from the ground and from space, are enabling new data-intensive approaches to a variety of problems in stellar and solar astrophysics. This talk describes four projects, each serving as a vignette of a different but complementary mode of data-intensive research into the formation and evolution of Sun-like stars. The SLoWPoKES project extracts from the Sloan Digital Sky Survey the largest sample of wide low-mass binaries ever assembled, which we use to constrain binary star formation theory and the role of third bodies in the formation of tight binaries. The EB Factory project seeks to identify rare, but astrophysically very interesting, case studies from among the large numbers of eclipsing binaries being harvested by surveys for transiting exoplanets. We use a set of rare low-mass and brown-dwarf eclipsing binaries to elucidate the role of magnetic activity in altering the basic properties of low-mass stars and brown dwarfs, affecting our understanding of the stellar initial mass function and the frequency of brown dwarfs in stellar populations. The X10000 Project studies the structures of young stellar coronae in order to understand the role of extreme coronal mass ejections in the angular momentum evolution of young stars. As a by-product of this work, we have determined the first robust empirical relationship between X-ray flare energy and coronal mass loss for the Sun. Finally, we use the Kepler database of precision light curves for 150,000 stars to present a new, “photometric variability HR diagram” which enables accurate determination of stellar surface gravities, improves our knowledge of exoplanet properties, and enhances our ability to identify the most radial-velocityquiet stars for exoplanet discovery.

 

We strongly encourage you to attend the colloquium in person. If that is
impossible, it is available over zoom at the following link:
https://us02web.zoom.us/j/88024178440?pwd=Sk5tRXdLVWJTc0RkUXEwblRaa3RvQT09

Event Details

Date:
Oct 21, 2021

Time:
3:30–5pm

Location:
4421 Sterling Hall, 3:30 pm Coffee and Cookies, 3:45 pm This will be a ZOOM talk.

Speaker Host:
TBD

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