5 Nov 2019 — On November 1st at 15:00 UTC, the LIGO and Virgo gravitational wave detectors resumed their search for gravitational waves after taking a planned month-long break to perform maintenance and upgrades. All three sites halted operations for the entire month of October. Virtually all of the work planned for LIGO’s two detectors was completed by October 31st. This included inspecting and cleaning of test masses, installation of additional baffles to reduce light scattering, replacing a turbomolecular vacuum pump, and removing an unused portion of the “H2” vacuum system. Virgo engineers focused on increasing the laser input power from 19 W to 26 W. The extent to which this work has improved the instruments’ sensitivities will be known in the weeks to come. The second half of LIGO’s third observing run will conclude on April 30th, 2020.
For more details, read the full news release at the LIGO Lab webpage.