Sheila, Camilla. Last done in 80451, followed those instructions.
Before translating the crystal, we reduced the green H1:SQZ-SHG_LAUNCH_DC_POWERMON power from 30mW down to 6mW. After we finished, we brought this up to 15mW and still could lock the OPO with 80uW on H1:SQZ-OPO_TRANS_LF_OUTPUT and around 6 on the ISS controlmon. Meaning our losses reduced significantly.
We moved from the 3rd spot from the left photo to the 4th spot from the left photo ( 34 x steps of 50 to the right and then 19 x steps of 10 to the right). We have previously used the 2nd, 3rd, and 5th spots from the left, there is 6 spots in total.
Measured NLG to be 8.8 (0.0787/0.00892, 76542). This is lower than what we usually run with 11 to 17 so means that this new spot has less losses but a worse NLG.
FDS is the same but ASQZ lower. Shiela said that this good and is expected with lower losses and mean there can be less mis-rotated ASQZ injected. Plot attached.
Tagging OpsInfo: This change will mean that for the next week or so we'll need to more regularly adjust the OPO TEC temperature, instructions are in 80461. Should be done pro-actively when relocking and if range is low in observing. If you adjust while in Observing, please tag Detchar in your alog.
Operators, please actually go out of Observing to make this temperature change (no need for pre-approval from me, if the range check indicates it needs doing).
This alog from October points out that these temperature changes are so successful at improving our range so quickly that it causes some problems for the astrophysical searches. This is entirely mitigated if we pop out of Observe during the change, then back in when the change is complete.