Craig, Jennie W.

In order to calibrate POPAIR_RF9 and RF18 PDs in terms of PRG9 and 45, we ran Craig's labutils/mod_depth_up_down_test.

We realised our mod depth up/down test from the other day was changing the gain of the POPAIR diodes to compensate the drop in optical gain as the modulation depths are changed.

We don't want this as it negates the change on the diodes we are trying to measure for our calibration.

Craig commented out these lines in the step_9 and step_45 functions.

We also were overestimating the PRG as the beam on IM4_TRANS PD was not well-centred.

In this log we stepped the alignment in lock to optimise on the IM4 TRANS QPD and the ISS array.

The mod-up-down-test was taken during low frequency measurements of new DARM.

Times RF9 was stepped down are 1394406378 GPS, then back up at 1394406438 GPS.

Times RF45 wa stepped down are 1394406448 GPS, then back up at 1394406508 GPS.

After this test Craig did more optimisation of the input alignment with IM 1 and 3.

Then I waited a bit and took another test. Both were done with a well thermalised IFO of more 10 hours lock.

Times RF9 was stepped down are 1394409674 GPS, then back up at 1394409735 GPS.

Times RF45 wa stepped down are 1394409744 GPS, then back up at  1394409804GPS.

First image is beam diverter that needs unshuttered for this test.

Second image shows the plots from the first test, third image shows the second test.