All gravitational waves detected so far have come from binary sources.
All gravitational wave sources detected so far originate from binary systems, from mergers between two black holes and two neutron stars, or a black hole and neutron star. Although astronomers in theory know that gravitational waves are also emitted by non-binary sources, such a signal has so far eluded detectors. In new research, scientists have shown that chaotic cocoons around newly dead stars or newly born black holes can be the source of gravitational waves that can be registered by gravitational wave detectors.
When a star runs out of nuclear fuel at the end of its life cycle, it balloons up and violently sheds its outer layers, an explosion known as a supernova. A dense core is left behind, which can be a white dwarf, a neutron star, or a black hole. If a dying star collapses into a black hole, it can form powerful polar jets of relativistic particles. The jets can collide with the collapsing layers of the star, potentially creating gravitational waves that can be detected by gravitational wave detectors.
A paper describing the research Presented in 242nd Meeting of the American Astronomical Society. The author who led the research, Ore. Gottlieb, says, “Our study is a call to action for society to look at cocoons as a source of gravitational waves. We know that cocoons emit electromagnetic radiation, so they may be multi-messenger events. By studying them, we can learn more about what happens in the interior of stars, the properties of jets, and their propagation in stellar explosions.
The LIGO-VIRGO-KAGRA collaboration launched its fourth race to detect gravitational waves, with the BlackGem Observatory searching for optical counterparts. Other ground-based and space-based astronomical instruments are ready to disrupt their planned operations to turn their gaze on any flagged source. A new gravitational wave source is expected to be discovered at least once every three days.