Department of Earth Science and Astronomy Graduate School of Arts and Sciences The University of Tokyo

Next Seminar Informations

（Earth Science）4/23 14:00 Bldg16-#829　

Komiya
Title: TBD

（Astrophysics）5/14 10:00 Bldg15-#409

Speaker: Dr. Jim Fuller (Caltech)
Title: Cosmic Death Spirals
Abstract: Stars, planets, and compact objects orbiting with small separations are some of the most interesting and important systems in astrophysics. In black hole progenitor stars, the spin of the black hole is determined by the angular momentum contained within the stellar core, which can be affected by a binary companion star. I will discuss our current understanding of angular momentum transport in stars, and why most black holes are expected to spin slowly. I will also discuss new calculations of tidal spin-up in massive binary stars that can produce more highly spinning black holes. In stellar binaries known as heartbeat stars, many of the same processes operate and can be observed directly, allowing for tests of tidal models. In short-period exoplanet systems, tidal resonances between stellar oscillations and the planet’s orbit can be sustained by a resonance locking process, driving inward migration of the planet until it is consumed.

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