“The Formation of Close Binaries and Planets”
The formation and orbital migration of close binaries and hot Jupiters 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. 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 will outline a fragmentation model that reproduces the observations. I will conclude by highlighting how close binaries suppress the formation of close (S-type) planets. Close binaries therefore substantially bias planet occurrence rates and the inferred trends with respect to host mass and metallicity.
Please note: Should you require any reasonable accommodations to ensure equal access and opportunity related to this event please contact Stacy Tiburzi at 734-764-3440 or stibu@umich.edu.
The formation and orbital migration of close binaries and hot Jupiters 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. 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 will outline a fragmentation model that reproduces the observations. I will conclude by highlighting how close binaries suppress the formation of close (S-type) planets. Close binaries therefore substantially bias planet occurrence rates and the inferred trends with respect to host mass and metallicity.
Please note: Should you require any reasonable accommodations to ensure equal access and opportunity related to this event please contact Stacy Tiburzi at 734-764-3440 or stibu@umich.edu.
Building: | West Hall |
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Website: | |
Event Type: | Lecture / Discussion |
Tags: | Astronomy, Climate and Space Sciences and Engineering, Lecture, Physics |
Source: | Happening @ Michigan from Department of Astronomy, Department of Physics, Michigan Institute for Research in Astrophysics |