Events

Francois Foucart

Tuesday, October 12 2021

4:00pm

Marlar lounge & via Zoom
(MIT COVID Pass users with valid attestations can attend in-person)

The merger of a neutron star with a stellar mass black hole is one of the main sources of gravitational waves detectable by current ground-based observatories (LIGO, Virgo, KAGRA). The first two detections of these mergers were in fact just performed in 2020, with more events expected in future observational runs of LIGO/Virgo/KAGRA. If the neutron star is tidally disrupted by its black hole companion, mass ejection during and after merger also powers bright electromagnetic transients, including gamma-ray bursts and kilonovae. The ejected matter then undergoes rapid neutron capture nucleosynthesis (r-process), leading to the production of many heavy elements (gold, platinum, uranium,…). Both gravitational wave and electromagnetic signals carry information about the properties of the dense matter at the core of neutron stars, an important unknown in nuclear physics today.

To properly understand the dynamics of black hole-neutron star mergers and model their expected gravitational wave and electromagnetic signals, general relativistic merger simulations are typically necessary. These simulations require the inclusion of a broad range of physical effects, including general relativity, magnetohydrodynamics, radiation transport, and nuclear physics. In this talk, I will review our current understanding of the physics of black hole-neutron star mergers, as well as the status of the simulations used to model the observable signals that these mergers power.

Speaker

    Francois Foucart, University of New Hampshire

Host

Event Contact

    Debbie Meinbresse