ryan.short@LIGO.ORG - posted 10:11, Thursday 02 June 2022 - last comment - 16:03, Wednesday 08 June 2022(63425)
Calibration measurements taken this morning
At Sheila's request, I took two calibration measurements this morning while at Nominal Low Noise:
2022-06-02_H1_DARM_OLGTF_LF_SS_5to1100Hz_15min.xml
2022-06-02_H1_PCAL2DARMTF_LF_SS_5to1100Hz_10min.xml
These functions can be found in the following directory:
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O3/H1/Measurements/FullIFOSensingTFs
Images attached to this report
Comments related to this report
Trending and snapshotting the state of the IFO during this lock stretch for future reference: The order of operations -- PCAL measurement then DARM OLG TF measurement, with both ending by 2022-06-02 16:48 UTC -- prior to re-engagement of ADS lines and power buildups becoming noisy prior to lock loss. - Input Power: 50 W into PSL, 40 W into PRM - Recycling Cavity Power Buildups Completely stable, IFO "thermalized" for more than an hour at the start of the measurement. - OMC Whitening and OMC PD mA: We're back (now permanently) on the well-characterized OMCA whitening path (indicated by the use of FM3 "antiWh" instead of FM8 "antiB" even though you can't see the filter module names in the time machine snapshot) - OMC Power Linearization DARM Offset: We servo to 10 [mA] on each DCPD as the DARM offset, for a total of 20 [mA]. Here's what the OMC screen looks like when we do it. The "Fringe Offset X0" is 8.4, and the physical offset -- if we use ~5 [mA/pm] from yesterday's sensing function analysis (enjoying all of its grains of salt), that's 20 [mA] / ~5 [mA/pm] = 4 [pm] DARM offset. - The LSC Control at the ETMs: the configurations of these gains and switch show we're driving all ETMX for TST, PUM, and UIM stages. - TCS Settings: are as shown here - Spot positions: are as shown here In short, the only difference (that I know of) between the data taken last week on May 25 2022 (measured LHO:63391, processed LHO:63405) is that we're now controlling DARM with an All ETMX actuator that mimic's O3's actuator configuration, rather than the interim "split" actuator, split between EX TST, EY PUM, and EY UIM. Some of the ndscope settings I used to capture these plots I made into to templates for further ease of use: /ligo/home/jeffrey.kissel/Templates/NDScope/ cal_excitations.yml darm_control_configuration.yml powerbuildups_40mintrend.yml spot_positions.yaml Maybe in some glorious future I can find the time to create a "CALIBRATING" screen that mimics Jenne's "LOCKING" screen that has all the pertinent information of things that we know have impacted the DARM loop in the past showing all these MEDM variables screenshotted here, and drop down launchers for these ndscope templates. One day...
Images attached to this comment
Later this day (local time) -- unfortunately not during the *exact* same lock stretch, but one right after it in the same configuration (afaik) -- I gathered a broad band transfer function for later use. In doing so, DTT was *very* uncooperative and would crash mid-measurement, leaving the injection still going. Bad bad bad, but it did allow me to go back in time and extract that data with the same template today. The broadband excitation was pushing PCAL into the IFO from 2022-06-03 00:29 to 00:37 UTC. (much longer than the normal 3 minute excitation, since I was scrambling to understand what was happening before I killed the PCAL model's test points to halt the excitation). I attach a trend of the times that I was injecting, and a screenshot of the post-processed data. After killing that BB injection, realizing I could do what I am doing here, I gave up trying to restart the broad band measurement. Wanting to get a swept sine suite within the same lock stretch I tried starting that after word. That failed too with a DTT crash (see the data from 00:38 to 00:40 in the trend), so I gave up entirely, killed the test point excitation again, and returned to nominal low noise. Anyways -- the BB data is still quite useful: The black trace is from 2022-05-23 before we switched from the "split EY + EX" actuator. The red trace is the "current" trace and configuration, where we're back on all EX. This is an apples to apples comparison between the two configurations.
Images attached to this comment
