The effects of heating on the ejecta of black hole-neutron star merger events

Summer 2016

Dhruv Desai : Physics/Applied Math

Mentor: Professor Daniel Kasen

Black hole-neutron star (BH-NS) mergers are remarkably exciting events to model, as they are a source of gravitational waves, same as those discovered for the first time by Advanced LIGO earlier this year. BHNS mergers are binary systems that consist of a black hole (BH) and a companion neutron star (NS), which under sufficient conditions, falls into the BH. After the merger of these two objects, an accretion disk typically forms around the BH and high-energy ejecta is flung out. Remnants of these mergers may power short gamma ray bursts and other electromagnetic signals. Studying these systems through numerical simulations can help better model, detect and interpret such events.

However, simulations have proven to be quite complicated. The post-merger disk evolution which occurs in these systems require a wide breadth of physics and numerical techniques to model, as well as necessitate the use of supercomputers. My research will focus on simulating the effects of heating from radioactive decays of neutron-rich nuclei in the ejecta. We will also visualize and analyze the long term evolution and properties of the disk that forms at late times.

I am very grateful to the Rose Hills Foundation for making my research possible with this fellowship. This being my last summer here at Cal, I am incredibly excited to do research in astrophysics, and I hope to get a better feel for life as a researcher. Thanks to the Rose Hills Foundation, I am able to follow my passion and further my career in physics.