Due to issues with running the report script locally (being worked on), Sudarshan will post the results of this past Tuesday's End Y Pcal calibration. Attached are pics of the logsheet so he has the pertinent information.
Other than the standard end station calibration measurements, I also removed the alignment irises that we installed the last time we fixed a clipping issue and tweaked the steering mirrors in the receiver module to recenter the beams into the RX integrating sphere as described in WP 7111.
TravisS, SudarshanK
Below is the link to the calibration trend document that includes the measurement done on Tuesday.
https://dcc.ligo.org/DocDB/0118/T1500131/016/D20170815_LHOY_PD_trend.pdf
After, Travis relieved the clipping on the receiver side by centering the beam in the optics and the integrating sphere, the TxPD and RxPD calibration seemed to have moved back to its non-clipping configuration. This also suggests that all the clipping we had seen during the last few months was all happening outside the vacuum in the receiver side module. Thanks Travis.
| Date | TxPD (N/V) | RxPD (N/V) | Remarks |
| 2017/05/24 |
1.5193e-09 |
1.0500e-09 |
Before Clipping |
| 2017/08/08 |
1.5202e-9* |
1.1111e-09 |
During Rx Clipping |
| 2017/08/15 |
1.5202e-09 |
1.0502e-09 |
After Clipping is relieved |
* This TxPD calibration was estimated by using the optical efficiency number from the 2017/05/24 measurement because of RxPD clipping. Details on LHO alog # 38090.