Frontier Research Institute for Interdisciplinary Sciences
Tohoku University

In the early universe, only light elements such as hydrogen and helium existed. Heavier elements such as carbon, which make up our bodies, have been synthesized by some astronomical phenomena throughout the long history of the universe. The origin of some of the heavy elements such as gold and platinum has remained a mystery for more than 60 years and is one of the big unsolved problems in astrophysics.

Coalescence of binary of compact objects (neutron stars or black holes) by the gravitational wave emission is one of the primary targets of the gravitational wave detectors currently in operation. Such a coalescence is expected to expel a part of the neutron star matter, in which the heavy-element synthesis takes place. The heavy-element production in the expelled matter results in a characteristic electromagnetic emission. The observation of the electromagnetic and gravitational waves from the phenomenon can help us to understand the origin of the heavy elements such as gold and platinum.

I use numerical simulations of the coalescence of the compact objects to predict the elements synthesized and the electromagnetic waves emitted by the phenomenon. By comparing them with observational data, I will explore the origin of heavy elements. I am also interested in understanding the nature of the coalescing compact stars by comparing the observed data with theoretical predictions. I am also studying astronomical phenomena involving strongly gravitating objects, including supernova explosions and the formation of the black holes at the end of the lives of massive stars.