After about a 5.5hr lock, noticed range slowly drifting down over several hours. With H1 out of Observing, took the opportunity to touch up the Squeezer with:
Jennie W, Rahul
Yesterday we made some measurements to calibrate the spot size on the QPD as we scan the beam position across it.
We used a connector Fil made us to plug in the OT301 QPD amplifier into a DC power supply after checking it contained voltage regulators that could cope with a voltage between 12 and 19 V ( as the unit says it expects DC supply but the previous one we were using was AC with a 100mA current rating and was getting too hot so we assume that was the incorrect one). We hooked it up at 16V (this draws about 150mA of current). The QPD readout looks normal and does not have any of the strange sawtooth we saw with the original power cable.
We moved the M2MS beam measurement system out of the way of the translation stage.
To calibrate the QPD we need to change the lateral position of the M1 mirror and lens to change the yaw positioning on the QPD and measure the X and Y voltages from the QPD.
We need to check we are centred first. The QPD bullseye readout shows the beam is off a tiny bit in yaw but this was as good as we could get at centering the beam when we moved the QPD. All 8 PDs are reading about 4.6 V so this means the beam is well centred in the array plane.
We measure 11000 counts on the bullseye qpd readout at this M1 position.
Translation Stage inch |
QPD X (mV ) |
QPD Y (V) |
---|---|---|
4.13 | 239e-3 | -1.77 |
4.14 | 252e-3 | -1.84 |
4.15 | 2.34 | -1.60 |
4.16 | 4.46 | -1.17 |
4.17 | 4.26 | -1.11 |
4.18 | 5.62 | -835e-3 |
4.19 | 7.80 | -600e-3 |
4.20 | 7.81 | -321e-3 |
4.21 | 8.45 | -222e-3 |
4.22 | 8.82 | +70.6e-3 |
4.23 |
9.19 |
771e-3 |
4.24 | 9.28 | 1.12 |
4.25 | 9.37 | 1.88 |
4.26 | 9.36 | 2.36 |
4.27 | 9.37 | 2.38 |
4.28 | 9.44 | 2.71 |
4.29 | 9.47 | 3.10 |
4.30 | 9.50 | 3.41 |
4.31 | 9.49 | 3.35 |
4.32 | 9.51 | 3.72 |
4.33 | 9.55 | 4.27 |
4.34 | 9.58 | 4.55 |
4.35 | 9.62 | 4.86 |
4.36 | 9.66 | 5.44 |
4.37 | 9.65 | 5.31 |
4.38 | 9.63 | 5.60 |
4.39 | 9.69 | 5.75 |
4.40 | 9.69 | 6.00 |
4.41 | 9.70 | 6.15 |
4.42 | 9.70 | 6.16 |
4.43 | 9.71 | 6.33 |
4.44 | 9.71 | 6.50 |
4.45 | 9.72 | 6.72 |
4.46 | 9.74 | 7.09 |
4.47 | 9.73 | 6.87 |
4.48 | 9.74 | 7.40 |
4.49 | 9.75 | 7.46 |
4.50 | 9.74 | 7.46 |
4.51 | 9.76 | 7.75 |
4.52 | 9.74 | 7.67 |
4.53 | 9.73 | 7.82 |
4.54 | 9.74 | 7.96 |
4.55 | 9.73 | 8.08 |
4.56 | 9.72 | 8.33 |
4.57 | 9.71 | 8.43 |
4.58 | 9.70 | 8.50 |
4.13 | 448e-3 | -1.98 |
4.12 | -1.02 | -2.34 |
4,11 | -1.17 | -2.14 |
4.10 | -2.92 | -2.43 |
4.09 | -4.63 | -3.30 |
4.08 | -5.91 | -3.18 |
4.07 | -6.97 | -3.40 |
4.06 | -8.17 | -4.24 |
4.05 | -8.13 | -4.28 |
4.04 | -8.52 | -4.47 |
4.03 | -8.76 | -4.77 |
4.02 | -8.89 | -5.27 |
4.01 | -9.01 | -5.45 |
4.0 | -9.08 | -5.44 |
3.99 | -9.10 | -5.85 |
3.98 | -9.11 | -5.91 |
3.97 | -9.11 | -5.93 |
3.96 | -9.12 | -6.16 |
3.95 | -9.12 | -6.18 |
3.94 | -9.13 | -6.34 |
3.93 | -9.13 | -6.49 |
3.92 | -9.12 | -6.49 |
3.91 | -9.13 | -6.61 |
3.90 | -9.11 | -6.55 |
3.89 | -9.11 | -6.70 |
3.88 | -9.10 | -6.46 |
4.13 | ||
I plotted the data from lowest reading on the translation stage to highest and fitted the linear region using Calibrate_QPD.m which is attached.
Data is shown in attached pdf.
The slop of the linear region in V/inch is 112 V/inch. Which means to if the beam moved 8.93 e-3 inches on the QPD in yaw, the yaw readout would change by 1 Volt.
I altered the code to plot in mm and the constant is 4.4 V/mm.
D'oh I read the scale on the translation stage wrong so the x readings are actually lower by a factor of 10.
This makes the slope 44.1 V/mm which is more in line with the 65.11 V/mm Mayank and Shiva found for the QPD calibration here.
Ours could be different because we have a slightly different beam size and we moved the QPD in its housing to centre it which could have changed X to Y coupling in the QPD readout.
This implies our beam diameter on the QPD is around 0.4mm which makes a lot more sense considering the diode is 3mm!
As a cross-check we used the QPD 'bullseye' readout unit and Rahul changed the translation stage in yaw and we measured the beam dropping from 10400 counts in the middle of the QPP to 100s of counts at the edges.
Translation Stage [inch] | QPD Sum Counts |
---|---|
0.413 | 10400 |
0.365 | 500 |
0.413 | 10400 |
0.49 | 400 |
diode size ~ ((0.49-0.365)*0.0254*1000) = 3.175 mm.
(Jordan V., Gerardo M.)
HAM3 annulus ion pump (AIP) railed today around 7:00 am this morning. We'll try to diagnose the system at the next opportunity. After the pump railed there is no noted effect inside the main vacuum envelope.
The AIP body was replaced last on 2015, see aLOG entry here.
Wed Jul 02 10:13:04 2025 INFO: Fill completed in 13min 1secs
FAMIS 26044, last checked in alog85153.
HAMs:
HAM4 has a new V3 line at the upper end of the frequency bandwith shown.
HAM7 V2 and V3 also appear a little louder just over 100 Hz.
HAM8s V3 line just over 100Hz has reduced by ~an order of magnitude.
BSCs:
ITMY_ST2 V2 has become a little noisier at high frequency.
BS_ST2 V3 has become a little noisier at high frequency.
ETMX_ST1 line at just under 60Hz has increased in both H1 and V3.
Tuesday morning I found that HWS ETMY camera control had stopped running at 06:27 PDT for unknown reasons. This was discovered when H1 went out of lock at the start of maintenance and the ETMY camera was not enabled. This was not an actual issue because the ETMY camera is turned off.
To bring attention if a camera controler stops running I made two changes the camera control system:
1) Added GPS times to the controller code (required loading python3-requests and python3-dateutil for gpstime)
2) Added run-status widgets to MEDM, if a camera controller's GPS falls behind by 5 minutes or more its MEDM shows a purple block
Attachment shows ETMY in a stopped state.
TITLE: 07/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 15mph Gusts, 8mph 3min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.05 μm/s
QUICK SUMMARY:
Rough night continues after Maintenance Day with rung up violins and input alignment shift.
NOTE: Well, after getting H1 back to 60W, the violins are not rung up and better than how they looked at the end of my shift yesterday.
(Sheila & Todd are now looking at the Squeezer & I returned H1 to be able to "Observe WITH Squeezing".)
I noticed ETMX mode1 has been high ever since coming back from maintenance yesterday and we usually don't damp this mode. I took a high res spectra to confirm that it was this mode and not another close line causing this and it was so I tried to find some damping settings.
Nothing worked all that well, some tentative new settings are FM1+FM2+FM10 G=-50.
Called again due to the squeezer FC, same as last time. I've checked and the OPO temp maxes out H1:SQZ-CLF_REFL_RF6_ABS_OUT, and the adjustment I made earlier to FC1 and FC2 gets H1:SQZ-FC_TRANS_C_LF_OUT almost at 100. The FC is losing lock at atmost the same spot - it's getting to TRANSITION_IR_LOCKING and is saying that green is losing lock either right after loading in the LSC matrix, or after the same spot as before, after changing the DOF1 gain to 0.
I don't know what else to try, so I ran Ryan Short's script for changing the default guardian SQZ states so that we could go into Observing without squeezing until I can contact someone at 13:00UTC.
We've been approved to continue to do Observing without Squeezing until people are able to look at the issue when they get onsite
H1 Manager called on me to help with a bunch of SDF diffs.
- Some ASC POP A offsets, which were accepted in safe earlier today (85490), so I went ahead and accepted them for Observe as well
- IMC PZT offset changes, which were made earlier when working on realigning the IMC (85476)
- ALSX camera offsets, which were changed earlier (85472)
- the SR3 and SRM dackill bypass times were lengthened temporarily for part of the work today, which I realize now should have been reverted oops need to fix when we're out of Observing tomorrow
- SQZ OPO servo's common board excitation had been left switched on (switch on the right from EXC A), so I just opened the switch
WP 12640
ECR E2400330
Drawing D0901284-v5
T2500232
Today we started upgrading the SUS Sat Amps per ECR E2400330. Modification improves the whitening stage to reduce ADC noise from 0.05 to 10 Hz. The following units were replaced with modified units:
Suspension | Old | New |
PRM TOP | S1100067 | S1100168 |
PRM/PR3 | S1000275 | S1100173 |
PR3 | S1100175 | S1100183 |
BS TOP | S1100090 | S1000291 |
BS RT/SD | S1100155 | S1100066 |
SR3 Top | S1000296 | S1000284 |
SR3/SRM | S1100178 | S1000290 |
SRM | S1100136 | S1100068 |
F. Clara, C. Gray, J. Kissel, O. Patane, M.Pirello
Here's the characterization data and fit results for S1100168, assigned to PRM M1's T1T2T3LF OSEMs (what Fil refers to as just "PRM TOP" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100168_PRM_M1_T1T2T3LF_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design PRM M1 S1100168 CH1 T1 0.0969 : 5.30 120.10 zpk([5.3],[0.0969],1,"n") CH2 T2 0.0950 : 5.20 120.25 zpk([5.2],[0.095],1,"n") CH3 T3 0.0950 : 5.18 120.25 zpk([5.18],[0.095],1,"n") CH4 LF 0.0940 : 5.15 120.00 zpk([5.15],[0.094],1,"n") The attached plot and machine readable .txt file are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ Even though I've fit for the transimpedance gain, I've elected *not* to include a gain in the foton design string relative to "ideal," as there are more scale factors in play that determine the overall [(meters)/(ADC cts)] scale in the calibration of the OSEMs (LED light power, PD response, any cable loss, ADC channel gain, etc.). Determining this overall scale is better left to different methods, a la LHO:84548, which we (eventually) anticipate doing for all SUS with ECR E2400330 upgraded satamps.
Here's the characterization data and fit results for S1100173 , assigned to PRM/PR3 M1's RTSD/T1T2 OSEMs (what Fil refers to as just "PRM/PR3" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100173_PRMPR3_M1_RTSDT1T2_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design PRMPR3 M1 S1100173 CH1 RT 0.0969 : 5.3 120.00 zpk([5.3],[0.0969],1,"n") CH2 SD 0.0955 : 5.22 120.00 zpk([5.22],[0.0955],1,"n") CH3 T1 0.0975 : 5.35 119.75 zpk([5.35],[0.0975],1,"n") CH4 T2 0.0975 : 5.33 120.25 zpk([5.33],[0.0975],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ See above LHO:85504 comment as to why an account of the fit transimpedance was not included in the foton design string gain.
Here's the characterization data and fit results for S1100183 , assigned to PR3 M1's T3LFRTSD OSEMs (what Fil refers to as just "PR3" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100183_PR3_M1_T3LFRTSD_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design PR3 M1 S1100183 CH1 T3 0.0950 : 5.19 120 zpk([5.19],[0.095],1,"n") CH2 LF 0.0945 : 5.17 120 zpk([5.17],[0.0945],1,"n") CH3 RT 0.0940 : 5.14 120 zpk([5.14],[0.094],1,"n") CH4 SD 0.0955 : 5.24 120 zpk([5.24],[0.0955],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ See above LHO:85504 comment as to why an account of the fit transimpedance was not included in the foton design string gain.
Here's the characterization data and fit results for S1000291 , assigned to BS M1's F1F2F3LF OSEMs (what Fil refers to as just "BS TOP" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1000291_BS_M1_F1F2F3LF_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design BS M1 S1000291 CH1 F1 0.096 : 5.19 121.50 zpk([5.19],[0.096],1,"n") CH2 F2 0.096 : 5.23 120.75 zpk([5.23],[0.096],1,"n") CH3 F3 0.096 : 5.26 120.00 zpk([5.26],[0.096],1,"n") CH4 LF 0.095 : 5.2 120.00 zpk([5.2],[0.095],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ See above LHO:85504 comment as to why an account of the fit transimpedance was not included in the foton design string gain.
Here's the characterization data and fit results for S1100066 , assigned to BS M1's RTSDxxxx OSEMs (with the 2x "xx" representing the unused channels not connected to anything in-vacuum. Fil refers to this as just "BS RT/SD" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100066_BS_M1_RTSDxxx_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design BS M1 S1100066 CH1 RT 0.0960 : 5.19 121.50 zpk([5.19],[0.096],1,"n") CH2 SD 0.0940 : 5.11 120.75 zpk([5.11],[0.094],1,"n") CH3 xx 0.0935 : 5.12 120.25 zpk([5.12],[0.0935],1,"n") CH4 xx 0.0965 : 5.26 120.50 zpk([5.26],[0.0965],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ See above LHO:85504 comment as to why an account of the fit transimpedance was not included in the foton design string gain.
Here's the characterization data and fit results for S1000284 , assigned to SR3 M1's T1T2T3LF OSEMs (Fil refers to this as just "SR3 Top" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1000284_SR3_M1_T1T2T3LF_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design SR3 M1 S1000284 CH1 T1 0.0960 : 5.25 120.1 zpk([5.25],[0.096],1,"n") CH2 T2 0.0950 : 5.2 120.1 zpk([5.2],[0.095],1,"n") CH3 T3 0.0960 : 5.27 120.1 zpk([5.27],[0.096],1,"n") CH4 LF 0.0945 : 5.16 120.5 zpk([5.16],[0.0945],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ See above LHO:85504 comment as to why an account of the fit transimpedance was not included in the foton design string gain.
Here's the characterization data and fit results for S1000290 , assigned to SR3/SRM M1's RTSD/T1T2 OSEMs (Fil refers to this as just "SR3/SRM" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1000290_SR3SRM_M1_RTSDT1T2_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design SR3/SRM M1 S1000290 CH1 RD 0.0955 : 5.21 120.1 zpk([5.21],[0.0955],1,"n") CH2 SD 0.0940 : 5.13 120.5 zpk([5.13],[0.094],1,"n") CH3 T1 0.0930 : 5.07 120.5 zpk([5.07],[0.093],1,"n") CH4 T2 0.0950 : 5.2 120.1 zpk([5.2],[0.095],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ See above LHO:85504 comment as to why an account of the fit transimpedance was not included in the foton design string gain.
Here's the characterization data and fit results for S1100068 , assigned to SRM M1's T3LFRTSD OSEMs (Fil refers to this as just "SRM" above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100068_SRM_M1_T3LFRTSD_20250630.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design SRM M1 S1100068 CH1 T3 0.094 : 5.14 120.10 zpk([5.14],[0.094],1,"n") CH2 LF 0.095 : 5.18 120.25 zpk([5.18],[0.095],1,"n") CH3 RT 0.096 : 5.23 120.75 zpk([5.23],[0.096],1,"n") CH4 SD 0.096 : 5.29 119.00 zpk([5.29],[0.096],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ See above LHO:85504 comment as to why an account of the fit transimpedance was not included in the foton design string gain.