peter.king@LIGO.ORG - posted 06:45, Monday 18 July 2016 - last comment - 07:10, Monday 18 July 2016(28464)
Laser trip
Richard called saying the laser was off when he entered the Control Room this morning.
According to the laser status screen, the laser tripped due to a crystal chiller flow rate
error, somewhere in the power meter circuit. Attached are two plots of the previous one day's
trend data.
The signal from head 2 is somewhat noisier than the signals for the 3 other heads. Looking
back even further it seems to have been that way for at least the 6 days. Unfortunately we do
not have enough diagnostics to pinpoint the location of the potential blockage and at this point
in time it is a bit of a waiting game unless time is scheduled for invasive maintenance.
After restarting the laser at ~06:30, things seem to have settled down by 06:40.
Images attached to this report
Comments related to this report
Attached is a plot of the high power oscillator's PZT voltage during the warm up time. During
the warm up, the injection locking broke lock once. Also attached is a trend plot of the PZT
voltage.
As another side note, I happened to notice that the FSS locked quite happily even though
the noise eater was off. This might be due to the reduced FAST gain.
Both shutters were open when the laser shut down.
Images attached to this comment
