Detecting gravitational waves with the LIGO-Virgo-KAGRA network: a look back at the O3 run, and a look forward to the incoming O4 run -- and beyond
Dr. Nicolas Arnaud
CNRS/EGO/IJCLab
After a long shutdown of three years (significantly extended by the consequences of the worldwide covid-19 pandemic), the LIGO-Virgo-KAGRA (LVK) network of ground-based gravitational-wave (GW) interferometric detectors is in the home stretch before the start of the fourth Observing Run, O4.
After an introduction to the search for GW by the LVK network and a brief summary of the first detections (most notably GW150914 and GW170817), I will discuss the main results of the past O3 run (April 2019 - March 2020). In addition to the detections themselves and to the information they provide regarding compact objects in the Universe, I will present a study of the impact of the environment on the performance on the Virgo detector during the 1-year O3 data taking.
Then, I will move to the O3-O4 upgrades and changes, both for the detectors and for the public alerts dispatched when GW signals are detected in low latency. Finally, I will conclude my talk by looking at the future of ground-based GW detection. Further upgrades of the current ("second-generation", or "advanced") instruments are already planned for the decade to come, while projects of third-generation detectors (Einstein Telescope in Europe, Cosmic Explorer in the US) are taking shape in parallel.