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We found the ITF struggling to lock due to high winds and PR control. So we decided to start with activities focussed on the ESQB without the ITF.

We mounted the two additional accelerometers on the ESQB in the two horizontal directions (X is parallel to the short side of the ESQB, Z is parallel to the long side of the bench).

Test 1 - Bench : We shook the ESQB table directly by pushing on the bench along X (Fig 1 in order of appearance), then Z directions. We measure dominant bench resonances at ~13 Hz and 21 Hz.

We then attached the Mini Accelerometer (Mini Acc) to various elements on the bench.

Test 2 - Cameras : The direction of the Mini Acc is parallel to the incident beam on the cameras. We excited motion using the impulse hammer on the table in all three axes for 30 seconds each. We observe resonances of the ESQB (as in Test 1), and a resonance ~72 Hz (Fig 2). We also did a tapping test on the camera mount itself, with a clearer response at ~ 72 Hz (Fig 3). We observe the same behaviour in both cameras.

Test 3 - Third Faraday Isolator Output Polarizer : We attached the Mini Acc parallel to the X direction to the support of the last polarizer. Without exciting the bench, the Mini Acc observes 46 Hz and 72 Hz as in the blue curve of Fig 4. We then excited with the bench with the hammer in all three axes, and tapping along the X direction. We observe the bench frequencies, as well as 46 Hz, 72 Hz, 94 Hz, 126 Hz, 150 Hz and 205 Hz, as in the purple curve of Fig 4.

Test 4 - Third Faraday Isolator Magnet : We attach the Mini Acc vertically on the Faraday magnet. Without exciting the bench, the Mini Acc observes 33 Hz, 36 Hz, 46 Hz, 48 Hz and 50 Hz as in the blue curve of Fig 5. We then excited with the bench with the hammer in all three axes. We did not observe the bench frequencies, but observed 33 Hz, 47 Hz, 51 Hz, 73 Hz, 95 Hz, 109 Hz, 125 Hz, 158 Hz, 176 Hz, 184 Hz, 207 Hz and 288 Hz as in the purple curve of Fig 5.

Test 5 - Third Faraday Isolator Output Polarizer Base: We attached the Mini Acc parallel to the X direction to the base of the support of the last polarizer, and we excited along the X direction with the impulse hammer. With no excitation, we observed 21 Hz, 46 Hz, 73 Hz, 94 Hz, 148 Hz and 205 Hz, as seen in the blue curve of Fig 6. We then excited the bench, seeing the same frequencies as well as 8 Hz and 13 Hz as seen in the purple curve of Fig 6.

Test 6 - Steering Mirror 1 : We attached the Mini Acc horizontally on the back the Mirror support, perpendicular to the mirror surface. We excited the table with the hammer in all three axes. In a quiet state, we observe 43 Hz and 152 Hz, as in the blue curve of Fig 7. By exciting along the x direction, we observe 13 Hz, 21 Hz, 25 Hz, 31 Hz, 43 Hz, 95 Hz, 106 Hz, 152 Hz, as in the purple curve of Fig 7.

Test 7 - Viewport/Flange : We changed the ADC config file to reconnect the accelerometer on the pipe (ENV_SQZ_PIPE_ACC_Y) instead of acquiring ENV_SQZ_MINI_ACC. We mounted the accelerometer in its usual Y direction, as well as switched it to the X direction (parallel to the pipe and beam), always tapping on the flange in the X direction. With the tapping and the accerometer in X, we observed peaks at 6.5 Hz, 13 Hz and 61 Hz, as in the purple curve of Fig 8. These weren't observed in a previous test (23 November) when the tapping was lighter.

In Summary, we are confident of:
* ESQB resonances at 13 Hz and 21 Hz
* The Faraday Isolator largest resonance responses at 33 Hz, 47 Hz and 72 Hz
* Steering Mirror 1 largest resonance responses at 43 Hz and 152 Hz