The current generation of gravitational wave detectors began observations in 2015 and have since confirmed 10 binary black hole merger events and one binary neutron star merger. This merger of two neutron stars was not only the first of its type to be detected in gravitational waves but the event was also detected in electromagnetic radiation.
"This radiation is the final and observable result of a complex fusion process that involves strong gravitation, heavy elements, neutrino physics, nucleosynthesis and radiation transport. Comparing our computer models with actual observations will help us to understand what really happens in such cosmic collisions," says Stephan Rosswog, professor of astrophysics at Stockholm University.
A new five-year Knut and Alice Wallenberg Foundationg grant led by Rosswog, and including OKC collaborators Anders Jerkstrand, Ariel Goodbar, Hiranya Peiris, and Jesper Sollerman, will support efforts to improve the modeling of neutron star mergers by increasing the timescale of simulations and better characterizing their electromagnetic emission. The improved models will be applied to the observations of future neutron star mergers in order to better understand the production of the heaviest elements, the properties of matter deep inside neutron stars, and to measure the expansion speed of the Universe.
The support of this grant means that future kilonova events will be studied for the entire path from their detection through their application to other areas of science, all at the OKC. With new simulations and data emulation techniques researchers will be able to respond rapidly to new gravitational wave detections. The OKC is also actively involved in the electromagnetic and neutrino follow-up of these events, giving them priority access to these data. Once a large enough sample of kilonovae have been detected and studied then they can be used for additional science, including as standard sirens to measure the expansion rate of our Universe.
"This is fantastic news for our team! This funding will strengthen our multidisciplinary research collaboration. It also gives us the long-term security to be able to tackle the challenges that are found in this new area," says Stephan Rosswog.