LIGO and Virgo: Another merger of two neutron stars?
The network of four gravitational wave detectors had barely started their third observation run when they registered another merger event of two neutron stars - with astonishing results.
LIGO and Virgo researchers finally released the long-awaited first signal from the third observing run of their gravitational-wave detectors. They have most likely observed the merger of two neutron stars using gravitational waves for the second time. Not only does this event come from a much greater distance than that of August 17, 2017, the overall mass of the system is also unexpectedly high. Since only LIGO and Virgo observed the event, another origin of the gravitational wave cannot be ruled out.
Since April 1, 2019, the network of four gravitational-wave detectors LIGO in Hanford and Livingston, USA, Virgo near Pisa, Italy, and GEO600 near Hanover have been listening to space again in the third observing run O3. They have already identified more than 40 signal candidates. All are freely available on the internet in real time with sky maps and information on their probable sources. The path from the signal candidate to the confirmed signal is long and (computationally) expensive. As in previous observation runs, it can take months before it is certain whether a candidate is real or not. For the fourth candidate from the third observation run, received and identified on April 25, 2019, the time has come: Candidate S190425z becomes signal GW190425! Extensive follow-up studies have confirmed its astrophysical origin…
