Dec 05, 2013

Keivan Stassun, Vanderbilt University

"“Star Formation, Solar Physics, and Stellar Astrophysics: A Data-Intensive Approach”"

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
vignetteof 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.

Event Details

Date:
Dec 05, 2013

Time:
3:30–5pm

Location:
4421 Sterling Hall

Notes:
Coffee served at 3:30pm; talk starts at 3:45pm

Speaker Host:
Barb Whitney / Ed Churchwell

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