Oli, Ivey, Edgard.
We used Oli's measurements from [LHO: 86204] to do an OSEM calibration for the PR3 M1 OSEMs. Here are the outputs of the calibration script.
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OSEM calibration of H1:SUS-PR3
Stage: M1
2025-08-05_1700 (UTC).
The suggested (calibrated) M1 OSEMINF gains are
(new T1) = 1.770 * (old T1) = 2.055
(new T2) = 1.547 * (old T2) = 1.544
(new T3) = 1.443 * (old T3) = 1.511
(new LF) = 1.590 * (old LF) = 1.862
(new RT) = 1.774 * (old RT) = 2.063
(new SD) = 1.543 * (old SD) = 1.639
To compensate for the OSEM gain changes, we estimate that the H1:SUS-PR3_M1_DAMP loops must be changed by factors of:
L gain = 0.596 * (old L gain)
T gain = 0.648 * (old T gain)
V gain = 0.617 * (old V gain)
R gain = 0.617 * (old R gain)
P gain = 0.670 * (old P gain)
Y gain = 0.596 * (old Y gain)
The calibration will change the apparent alignment of the suspension as seen by the at the M1 OSEMs
NOTE: The actual alignment of the suspension will NOT change as a result of the calibration process
The changes are computed as (osem2eul) * gain * inv(osem2eul).
Using the alignments from 2025-08-05_1700 (UTC) as a reference, the new apparent alingments are:
DOF Previous value New value Apparent change
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L -57.1 um -33.6 um +23.5 um
T -101.3 um -65.6 um +35.7 um
V 62.4 um 36.6 um -25.8 um
R 433.5 urad 225.7 urad -207.8 urad
P -631.8 urad -406.5 urad +225.2 urad
Y -166.7 urad -76.1 urad +90.5 urad
We have estimated a OSEM calibration of H1 PR3 M1 using HAM2 ST1 drives from 2025-05-21_0000 (UTC).
We fit the response M1_DAMP/HAM2_SUSPOINT between 5 and 15 Hz to get a calibration in [OSEM m]/[GS13 m]
This message was generated automatically by OSEM_calibration_SR3.py on 2025-08-06 01:07:57.985744+00:00 UTC
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EXTRA INFORMATION
The H1:SUS-PR3_M1_OSEMINF gains at the time of measurement were:
(old) T1: 1.161
(old) T2: 0.998
(old) T3: 1.047
(old) LF: 1.171
(old) RT: 1.163
(old) SD: 1.062
The matrix to convert from the old Euler dofs to the (calibrated) new Euler dofs is:
+0.596 -0.0 +0.0 -0.0 +0.0 -0.003
+0.0 +0.648 -0.0 +0.0 +0.0 -0.0
-0.0 +0.0 +0.617 -0.004 +0.001 +0.0
+0.0 +0.0 -0.748 +0.617 -0.007 -0.0
+0.0 +0.0 +0.517 -0.036 +0.67 -0.0
-0.407 +0.0 -0.0 +0.0 -0.0 +0.596
The matrix is used as (M) * (old EUL dof) = (new EUL dof)
The dof ordering is ('L', 'T', 'V', 'R', 'P', 'Y')