[Kenta, Masayuki]

Now we can output up to about 10 W from the PSL.

• HWP of the PSL output has been recovered with 'click-sound technique (found by Oshino-san)'.
• I knew that the PMC TRANS is too small (roughly 50 %), and it was due to the mode hop of the laser source. I found that the temperature control of the laser crystal was disconnected due to the TTFSS servo removing work and that changed  the operation temperature to where the mode hop occures. Before, the laser tempertture was controled via TTFSS servo. The reason for that was just because we controled the laser temperature in RefCav loop. We only changed the software(RTM) and did not change hardware (cabling) when we removed the RefCav control loop from the IOO and  implemented the laser temperature loop for the IMC control in Nov 2019. We connected the Dsub-BNC converter to the laser temperature control, and now it is working well.
• One concern is that the current connection of the laser temperture loop has no LPF. The other reason why we used the TTFSS for the temperature control is that the TTFSS has LPF for the laser temperature control. I guess it might not be the problem, but possibly new connection introduce the frequency noise. We should check it with arm cavity at some point.