[Marc, Shalika]

We relocked SHG without issue.

We changed the HPD bias of MZ from 3.4V to 6.2V to minimize the reflected power (now looking like some 4th order mode).

We tuned a bit the steering mirror just after the MZ to maximize GRMC transmission.

We blocked  one arm of the MZ and realigned the beam into the GRMC with the previous steering mirror and one mirror of the MZ.

Then, we blocked the other arm of the MZ and realigned this path with the other MZ mirror.

We minimized the polarization peak by rotating the HWP before the MZ from 218.5 deg to 219.5 deg.

We measured the mode-matching of arm 1 and 2 to be 81.9% and 86.1%, respectively.

We modified DDS2 config so that DAC 0,1,2 provide 88.3 MHz.

We tuned the phase of DAC 2 (GRMC demod) from 125 deg to 165 deg to recover the expected error signal shape. The peak to peak value is about 114mV while it was 10 times larger in the past.

Then, we were able to lock GRMC.

However, we had some issues to lock the MZ : when we connect the servo out of MZ to the HPD of MZ we can hear some sound and clear misalignment..

Related curves will be uploaded soon