Jennie W, Keita K, Betsy W, Camilla C

At the end of the day (for the day's activities to get to this point see Sheila's alog #89701) we were in chamber trying to see PRMI flashes in the POP in-vac path on -Y side of HAM1. We tried to lock JAC at 20W input so the flashses would be clearer on the card but it turns out anything over about 5W input puts the trigger PD above its threshold so the shutter in front of the JAC REFL PD and JAC WFS QPDS closes. Keita had Camill and I measure the power and for 2W input we get 5-6mW on this REFL PD and around 3mW on each QPD. This means that we shouldn't try and raise the trigger threshold (currently at 1.2V) as at 20W we will have 50mW on the REFL PD. I thought we had more of a margin than this.

What this means is we want to lock the JAC every time at 2W and then scale the gain in lock so only a low level of power goes to the REFL PD.

I copied some code from the ISC_library to do this. The new function is the state decorator JAC_pwr_adjust_function. It should scale the gain in JAC-L_SERVO by the requested input power as measured at IMC-PWR_IN_OUTMON while the JAC-LOCK guardian is in the 'LOCKED' state. It compiles now but I haven't tested it on the IFO yet as we left IMC and JAC in down, the input power at 100mW and the lightpipe closed at the end of the day.