Gravitational wave sources in the era of multi-frequency gravitational wave astronomy

Understand

The focus of this Chapter is on describing the prospective sources of the gravitational wave universe accessible to present and future observations, from kHz, to mHz down to nano-Hz frequencies.

• The multi-frequency gravitational wave universe gives a deep view into the cosmos, inaccessible otherwise.
• It has as main actors core-collapsing massive stars, neutron stars, coalescing compact object binaries of different flavours and stellar origin, coalescing massive black hole binaries, extreme mass ratio inspirals, and possibly the very early universe itself.
• Here, we highlight the science aims and describe the gravitational wave signals expected from the sources and the information gathered in it.