Events at Physics |
Events on Thursday, October 21st, 2021
- Astronomy Colloquium
- Star Formation, Solar Physics, and Stellar Astrophysics: A Data-Intensive Approach
- Time: 3:30 pm - 5:00 pm
- Place: 4421 Sterling Hall, Coffee and Cookies at 3:30 pm, Talk starts at 3:45 pm
- Speaker: Keivan Stassun, Vanderbilt University
- Abstract: 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-velocity quiet 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:
- Host: THIS IS A ZOOM TALK.