[Sheila, Karmeng]
Today we checked and managed to reduce some of the saturation on ZM4, and offload it onto ZM6. The changes were undone for now.
We briefly did the power budget check, but the power measured at the output of the SFI1 is fluctuating (between 0.79mW to 1.6mW) when the input to SFI1 is at 0.79mW. The power is stable down the propagation (after AP1 and SFI2), unsure what causes the fluctuation. Will continue to look into this tomorrow.
We also did an OMC scan, the pink trace is the scan when ZM4 is in its original setting (YAW: 1779.5), and the red trace is correspond to ZM4 misalignment (YAW: 1769.5).
It seems that when these OMC scans were being done, the SQZ ASC settings used were:
H1:SQZ-ASC_INMATRIX_P_1_5 (AS_A DC to POS) = Pitch +10, Yaw +30
H1:SQZ-ASC_INMATRIX_P_2_6 (AS_B DC to ANG) = Pitch -10, Yaw +10
H1:SQZ-ASC_OUTMATRIX_P_2_2 (ANG to ZM5) = 1 for Pitch and Yaw
H1:SQZ-ASC_OUTMATRIX_P_3_1 (POS to ZM6) = 1 for Pitch and Yaw
After struggling to get OMC scan with HAM6 at air, we looked back at this data. The misalignment peak is very large, but this should still give us an upper limit on mode matching. Data attached. This is 1.18% which is very good and better than we got with the old OPO which was always >2%, e.g. 86965.
PSAMS at ZM4 6.0V, ZM5 -0.4V
| Dark | TEM00 | TEM02 |
Mismatch*
(% of TEM02)
|
|
| ZM4 misalignment (YAW: 1769.5) | -0.002855 | 0.30352 | 0.000792 | 1.18% |
| ZM4 is in its original setting (YAW: 1779.5) | trouble with nds2 getting data |
*calculated with TEM02 / (TEM00 + TEM02)
