[Stefan, Kiwamu]
Here are our corner locking activity today.
We completed the alignment of all the diodes on ISCT1:
The razor blade beam dumps for the POP PDs are not aligned yet because the beam was not bright enough.
The demod phase of 2f signals were adjusted:
We adjusted the demod phases to get the signals maximized in I. When the 2f signals go positive, it indicates that the carrier is resonant in the power recycling cavity, and negative for the sidebands on resonance.
Note that the demod board that currently in the rack is not the final version (see alog 9103 and 9093).
The signals looked too small for the simple Michelson:
We misaligned PRM to see how big signal we could get for the simple Michelson. However, the RF and DC signals looked too small to acquire the lock. For example, REFLAIR_A_LF fluctuated only by a few ADC counts. It seems that it would be very tough to lock the Michelson without the power recycling at this power level.
PRM and PR2 are saturating:
We then moved onto PRX in order to establish stable lock of PRC. Wth both PRM and PR2 actuated, we could still see a saturation in them. We must revisit the multiple-stage offload in PRM and PR2 and activate the top stage stably. Currently none of the M1 stages are not in use because we haven't commissioned them. Also, at the same time, we should spend some time to reduce the seismic disturbance in the first place to ease the PRC lock.