LIGO and VIRGO are set to resume their hunt for gravitational waves - ripples in space and time - on April 1. One of the key features of this round of search, which is also called O3, is employment of a technique called "squeezing” to reduce levels of quantum noise that can mask faint gravitational-wave signals. This technique was developed at ANU's Centre for Gravitational Physics, lead by Prof. David McClelland. As the result of the latest upgrades, the LIGO detectors are now about 40% more sensitive compared with the last two rounds of search, which means that they can survey an even larger volume of space for powerful, wave-making events, such as the collisions of black holes.

Joining the search will be Virgo, the gravitational-wave detector located at the European Gravitational Observatory (EGO) in Italy, which has almost doubled its sensitivity since its last run and is also starting up April 1. So far LIGO and Virgo have seen ten binary black holes and one binary neutron star. In O3, the researchers are hoping to detect gravitational wave signals from new types of events such as binaries containing both a neutron star and a black hole or continuous gravitational waves from rotating neutron stars.

• LIGO Scientific Collaboration<
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