I ploted the result of the sensing matrixs with linear.(PDF files) But I haven't been able to plot it on a log scale yet.

However, since the excitation signals of PR3_PIT and PRM_PIT did not appear in the oplev, I calculated the conversion efficiency from the excitation signal to the OPLEV signal from the measurement results on 2024/09/03. (FIG1,2) I then multiplied this conversion efficiency by the WFS signal/excitation signal. Also, since the phase of this conversion efficiency was 90 degrees, I multiplied by 90 degrees to the WFS signal/excitation signal.

**** I uploaded this post once but the YAW plot showed PIT results. I re-plotted and re-posted it.

Linearity Confirmation for the DHARD_Y and CHARD_Y with Ushiba-san and KTanaka-san.

Details

• We checked the linearity of the CHARD_Y and DHARD_Y signal with injecting 28.125 Hz signal on `K1:ASC-DHARD_Y_SM_EXC` or `K1:ASC-CHARD_Y_SM_EXC`.
• The counts we used are 1, 50, 300 for DHARD_Y, and 30, 300, 1000, 2000 for CHARD_Y.
• The measured result (such as coherence between AS_QPDA1_RF17_{I,Q}_YAW and WIT ch on ETMX) did not have linearity and reproducibility, which is strange.
• But without any critical changes on the loop, it could reach ENGAGE_ARM_BPC of ASC_LOCK with ENGAGE_WFSDC of LSC_LOCK.
• Our plan is that measure the signal with this loop closed to have a good IFO alignment during the measurement. This is because we found the power breath on AS port during the measurement, which might be caused by the alignment flactuation.
• The diaggui files are in /users/Commissioning/data/ASC/2024/sensingmatrix/0909/

• Ushiba-san found that linearity and reproducability seems to be good when the excitation frequency was 6.125 Hz in the DHARD Y and CHARD Y case. For now, we are not sure of the reason why. Fig. 1 the calculation results from the measurement files when we excited the CHARD YAW at 6.125 Hz and changed the excitation amplitude. the values From Line 2 to Line 9 in fig.1 is the WFS responce and demod. phase when the excitation amp. was 1000 cnts, the values From Line 10 to Line 17 in fig.1 is when the amp. was 100 cnts, and the values from Line 18 to Line 25 is when the amp. was 1000 cnts. Also, Fig. 2 the calculation results from the measurement files when we excited the DHARD YAW at 6.125 Hz and changed the excitation amplitude. the values From Line 2 to Line 9 in fig.1 is the WFS responce and demod. phase when the excitation amp. was 30 cnts, the values From Line 10 to Line 17 in fig.1 is when the amp. was 100 cnts, and the values from Line 18 to Line 25 is when the amp. was 300 cnts.
• I checked the linearity and rreproduability of DSOFT Y when I changed the amplitude from 30 cnts, 100 cnts, 300 cnts, and 1000 cnts. Fig. 3 is the result.
• it seems to be consistent with each case...? We need to check other DoFs.

  •  

Following advice from Ushiba-san and Tanaka-san, I wrote the code to load the sensing matrix data using the io-function from the diaggui file and the code to plot it.

path: /users/Commissioning/scripts/asc/{WFS_dataload.py, WFS_plot_sensingmatrix.py}

I also plotted the data of 9/5.(FIG1-FIG8) In pitch direction, I plotted the sensing matrix without the PR2 and PRM, becouse its actuator is different the other DOF . And I confirmed only the ASport results for DHARD_YAW.  It matches the diaggui measurements(FIG9) and Sensingmatrix plots in this dof.

I also could plot as log scale.(FIG10-FIG17)

With KTanaka-san

We measured the sensing information again with new injection frequencies.
This is because the linearity and reproductivity of the result were not good with 28.125Hz we used before as reported.
We used 12.125Hz for pitch and 6.125Hz for yaw. (We have checked that there is not any peak on the suspension TFs.)
Due to conflicts with other work, we were unable to complete all measurements.

Directory we used: `/users/Commissioning/data/ASC/2024/sensingmatrix/0910`
The file names are {CSOFT, CHARD, DSOFT, DHARD, BS, PRM}_{P,Y}_{6,13}-125Hz_{100, 300}-cnt.xml

• What we measured by 15:00 JST.
  • CSOFT-Y -> CSOFT_Y_6-125Hz_100-cnt.xml, CSOFT_Y_6-125Hz_300-cnt.xml
  • CHARD-P -> CHARD_P_13-125Hz_100-cnt.xml, CHARD_P_13-125Hz_300-cnt.xml
  • DHARD-P -> DHARD_P_13-125Hz_100-cnt.xml, DHARD_P_13-125Hz_300-cnt.xml
  • DSOFT-P -> DSOFT_P_13-125Hz_100-cnt.xml, DSOFT_P_13-125Hz_300-cnt_old.xml
  • Because the alignment looked worse, we performed alignment adjustment with the ASC_SERVO_VIEW_ARM.adl
  • Again: DSOFT_P_13-125Hz_300-cnt.xml
  • CSOFT-P -> CSOFT_P_13-125Hz_100-cnt.xml, CSOFT_P_13-125Hz_300-cnt.xml
  • CHARD-Y -> CHARD_Y_6-125Hz_300-cnt.xml
  • BS-P -> BS_P_13-125Hz_100-cnt.xml, BS_P_13-125Hz_300-cnt.xml
  • BS-Y -> BS_Y_13-125Hz_100-cnt.xml, BS_Y_13-125Hz_300-cnt.xml
  • PRM-P -> PRM_P_13-125Hz_100-cnt.xml, PRM_P_13-125Hz_300-cnt.xml
  • PRM-Y -> PRM_Y_6-125Hz_100-cnt.xml, PRM_Y_6-125Hz_300-cnt.xml
  • PR2 -> not yet
  • PR3 -> not yet
  • IMMT2 -> not yet
  • IMMT1 -> not yet

[Ushiba, Aso, Hirose, Tanaka]

(2024.09.11 work)

## Abstract

We measured the sensing matrix for remained DoF. The linearity seems not to be so bad. Although we implement temporal ASC to improve the contrast, it seems not to change the results.

## What we did

• We continued this measurement for the remained DoFs (PR2, PR3, IMMT2, IMMT1 P and Y). We checked the linearity of the measurement by changing the excitaiton amplitude. The measurement datas were stored in "/users/Commissioning/data/ASC/2024/sensingmatrix/0910/". (And today(2024/09/12), I found we forgot to measure DHARD/DSOFT YAW with 300cnts. So I meaured them today.)
• Fig.1 - 20 show the result, The values below the "data = '/users/Commissioning/data/ASC/2024/sensingmatrix/0910/{Alignment DoF}_P (or Y)_13(or 6)-125_{100, 10}-cnt.xml'" line are the WFS responce when we excited the corresponding alignment DoF in Pithc (or Yaw) direction with 100 (or 10 in the case of PR3) cnts as the excitation amplitude. The values below the "data = '/users/Commissioning/data/ASC/2024/sensingmatrix/0910/{Alignment DoF}_P (or Y)_13(or 6)-125_{300, 30}-cnt.xml'" line are the WFS responce when we excited the corresponding alignment DoF in Pitch (or Yaw) direction with 300 (or 30 in the case of PR3) cnts as the excitation amplitude. In the PR3 case, the excitation by 100 cnt seemed to be too large because both trans. power shaked largely by the oscillation. So we reduced the excitation amplitude when we excited PR3 and PR2. (Honestly speaking, we can excite with 100 cnts when we excite PR2). The radial distance and the phase were obtained by the following equations. (In this time, we have not consider each coherence is large enough yet.)
  • $\text{Radial distance} = \sqrt{\left(\frac{\text{WFS I}}{\text{oplev}}\right)^2 +　\left(\frac{\text{WFS Q}}{\text{oplev}}\right)^2}$
  • $\text{Phase} = arctan(\frac{\text{WFS Q}/\text{oplev}}{\text{WFS I}/\text{oplev}})$
• For the almost DoFs, each value of WFS response seems to be somehow consistent even though each excitaion amplitude was changed. So the linearity is not so bad. (For DSOFT P, the linearity seems to be somehow suspectable.)
• After that, we tried to engage previous ASC of HARD, SOFT modes to check whether the results, especially ASQPD results were changed or not with the somehow good contrast. First, since PRFPMI seems to lose the lock within 10 mins when the previous ASC was engaged, we reduced the gains of HARD loops from -1 to -0.5 and engaged the previous ASC. However, the DHARD YAW seemed to start the oscillation at about 0.4 Hz. We tried to reduce the gain further, but the situation seems not to be improved. We restored the gain to -1. the situation was not changed.
• We measured the TF from actuators (Type-As) to sensors (AS WFS) of DHARD YAW and compared the TF (fig.21) with the model (fig.22). They seems to be consistent. Also the OLTF model used by the TF model seems to be stable anywherer below 1 Hz (fig.23). So the DHARD YAW itself seems to be stable and not to be the cause of the 0.4 Hz oscillation.
• Then, we tried to engage only HARD loops. We succeeded in closing the loops. we measured the TF from actuators (Type-As) to sensors (TMSX QPDs) of XSOFT in this state. Unfortunately, all of Type-As started to oscillate at 1.1 Hz maybe because the excitation for this measurement seemed to kick the 1.1 Hz mode (according to the TypeA eignemode model, RM Yaw chain-0th?). Then we reduced the HARD loop gain from -1 to -0.3. Then, the oscillation seemed to disappear.
• We found each trans. power decreased gradually. According to ETMX TCam image, the beam spot seemed to shift from the TM center. we considered each beam axis drifted with each SOFT mode. Then, we tried to engage the BPC for each ETM using each SOFT mode in the DC region. The XSOFT BPC seems to work well and the trans. power improved somehow. However, in the YSOFT BPC case, the error signal did not become 0 and did not move from some value. We tried to improve by increasing the gain or flipping the sign, but the situation was not changed. (Maybe current HARD loops cancelled the actuation of the SOFT mode.) Anyway, the trans. powers are not maximum but stable. And the AS contrast seems to be improved. We measured the WFS responce about CHARD P in this state.
• Fig.24 shows the result, The values below the "data = '/users/Commissioning/data/ASC/2024/sensingmatrix/0910/CHARD_P_13-125_100-cnt_withASC.xml'" line are the WFS responce with ASC. The values below the "data = '/users/Commissioning/data/ASC/2024/sensingmatrix/0910/CHARD_P_13-125_100-cnt.xml'" line are the WFS responce without ASC. Unfortunately, we could not see the significant difference of the linearity between with and without ASC. the bad contrast seems not to be the cause that CHARD P motion can see in AS WFS.