3 Oct 2019 — On October 1st, LIGO’s Hanford (LHO) and Livingston (LLO) detectors will temporarily halt observations to undergo a series of instrument upgrades and fixes. This kind of “commissioning break” sometimes occurs during LIGO’s long observing runs. The current run, O3, began on April 1 2019, when Virgo, the European-based gravitational-wave detector, located at the European Gravitational Observatory (EGO) in Italy, also started observing. Virgo is also pausing this month to perform upgrades that will improve their sensitivity and their uptime. All three detectors will resume operations on November 1st.
Commissioning breaks are typically month-long breaks during observing runs (as opposed to year-or-more long breaks between observing runs) when staff can make upgrades or repairs that would take more time than is available during weekly maintenance windows. The longer break gives the observatory sites an opportunity to make sure they are working optimally for the duration of the observing run, which in this case is scheduled to end on April 30, 2020.
For more details, read the full story at the LIGO Lab webpage.