Shift time: 2020-04-17 01:00-09:00 JST
(a.k.a. April 16 owl shift)

Operator: YamamotoT
Co-operator: Darkhan

Control room support: Yokozawa
Remote support: Miyoki

Summary

Environment:

• Some seismic noise and an earthquake at 6:30 am,
• low oceanic noise,
• several human-noise spikes

BNS range: 480-545 kpc

Duty cycle: 57.7 %

Log (all times are given in JST)

01:00 Shift started. Locked, observing with the BNS range 537 kpc.
IFO was locked for 2h 21m when the shift started.

02:00 Lost lock. Last lock duration: 3h 21m.
Within several minutes before the lock was lost, the BNS range gradually decreased to ~390 kpc.

02:14 Started S-Alignment after the LSC_LOCK guardian failed to re-acquire lock multiple times.
PR2 tripped several times during S-Alignment.

02:54 Locked, observing. IMC output: 4 W, BNS range: 545 kpc.
We managed to re-acquire lock after manually restoring PIT and YAW alignment of both ETMX and ETMY according to OPLEV values from one hour prior (see attached XARM and YARM oplev values).

• ETMX PIT: 0.3, YAW: -4.4
• ETMY PIT: 18.5, YAW: 8.5

05:21 Lost lock. Last lock duration: 2h 28m.

05:29 Locked, observing. IMC output: 4.3 W, BNS range: 480 - 545 kpc.
This time LSC_LOCK guardian was able to re-acquire lock without any issues.

06:30 Lost lock due to an earthquake. Last lock duration: 1h 01m.
Requested the DOWN state.

06:48 Requested ALS_DARM_LOCK.
ETMY ISC watchdog tripped within 1-2 minutes of reaching the ALS_DARM_LOCK state, requested the DOWN state for now.

07:46 Locked, observing. IMC output: 4 W BNS range: 439 kpc.

07:54 Lost lock. Last lock duration: 8m.

07:55 Started semi-manual alignment.

08:30 PR2 watchdog continues to trip.

09:00 Shift Ended

09:10 Masayuki came to the control room