Date:
Wednesday, June 27, 2018, 1:30pm to 2:30pm
Location:
Pratt
"The Formation and Evolution of Close Binaries and Planets "
Abstract: The formation and orbital migration of close binaries and
planets remain a mystery. The majority of very close binaries have
outer tertiary companions, suggesting Kozai-Lidov oscillations coupled
with tidal friction play an important role in their dynamical
evolution. However, close pre-main-sequence binaries are ubiquitous,
indicating most close binaries migrated within a few Myr while there
was still dissipative gas in the primordial disk. I will overview a
new population synthesis model that incorporates more realistic
initial conditions and a novel tidal mechanism to explain the
formation of close binaries and hot Jupiters during the
pre-main-sequence phase. The close binary fraction and Jovian planet
occurrence rate both increase with stellar mass, providing insights
into their respective formation processes. Although planets may favor
metal-rich hosts, recent observations demonstrate the close binary
fraction dramatically increases toward lower metallicities. I will
discuss five different observational techniques that corroborate this
metallicity trend and outline a fragmentation model that reproduces
the observations. I will also highlight the implications for Type Ia
supernovae, mergers of compact remnants, and biases in the inferred
planet statistics.