The Laser Interferometer Space Antenna (LISA) is a European Space Agency mission designed to detect and accurately measure gravitational waves. These are the tiny ripples in the fabric of space-time, relating to astronomical sources. It is anticipated that the LISA project will further open a window to understanding the universe.
A new study, from Northwestern University, is first to use realistic globular cluster models to make detailed predictions of LISA sources, in anticipation of the technology coming on line. These new sources of astronomical phenomena are expected contain multiple combinations of black holes, neutron stars and white dwarf components. This should be a rich stream of data which will be of great interest to astronomers and astrophysicists.
A globular cluster is a spherical structure of hundreds of thousands to millions of stars, gravitationally bound together. The clusters are some of the oldest populations of stars in the galaxy. Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers.
Northwestern University has reported on a range of detections this year, comprising of four binary black holes and a pair of neutron stars. To add to these, in terms of future developments, the university has been assisting with the next-generation observatory LISA, which is expected to be in space by 2034. The new detector will be sensitive to gravitational waves of a lower frequency than those that can be detected by the Earth-bound Laser Interferometer Gravitational-Wave Observatory (LIGO).
Based on a new Northwestern University study, it is predicted that dozens of binaries in the globular clusters of the Milky Way will be detectable. These binary sources should contain all combinations of black hole, neutron star and white dwarf components. Binaries that are formed from these star-dense clusters are expected to possess many different features from those binaries that formed in isolation, far from other stars.
The study is the first to use realistic globular cluster models to make detailed predictions of LISA sources. The study has been published as “LISA Sources in Milky-Way Globular Clusters” in the journal Physical Review Letters.
