40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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Entry  Fri Nov 6 18:38:00 2020, Koji, General, General, Powermeter lent from OMC Lab to 2um ECDL 
Thorlabs' powermeter controler + S401C head was lent from OMC Lab. Returned to OMC Jul 15, 2022 KA

Entry  Thu Nov 30 12:18:41 2017, Stephen, General, General, Preparation for Modal Testing on 4 December 
Norna Robertson, Stephen Appert ||  29 Nov 2017, 2 pm to 4 pm  ||  227 Downs, CIT

We made some preparations for modal testing, but did not have enough time to make measurements. Below is an after-the-fact log, including some
observations and photos of the current state of the OMC bench.
Entry  Fri Sep 8 15:14:05 2017, Koji, Facility, General, Preparation for the plumbing work 7x
[Steve, Aaron, Koji]

We've finished the preparation for the forthcoming plumbing work on (nominally) Sept 16th Saturday.
We've covered most of the west side of the OMC lab with plastic sheets and wraps.
Entry  Mon Aug 15 10:09:10 2016, Koji, General, General, Prev H1 OMC shipped to CIT 
Previous H1 OMC shipped from LHO to CIT

Entry  Tue Dec 18 20:04:40 2012, Koji, Optics, Characterization, Prism Thickness Measurement prism.png
The thicknesses of the prism mirrors (A1-A5) were measured with micrometer thickness gauge.
Since the thickness of the thinner side (side1) depends on the depth used for the measurement,
it is not accurate. Unit in mm.
Entry  Thu Jan 19 20:57:53 2017, Koji, Supply, General, Purchase 

Office Depot
v AA battery Qty. 24
    Reply  Thu Feb 16 17:23:12 2017, Koji, Supply, General, Purchase 

BNC Patch Panel

8x Amphenol Connex 112443 / Isolated BNC FEMALE TO FEMALE BULKHEAD ISOLATED ADAPTER - 50 ohm

Diameter: 13mm (0.512") D width 12.10mm (0.477")

4x Amphenol RF 31-4803-75 (75Ohm)

Entry  Thu Apr 4 20:07:39 2019, Koji, Supply, General, Purchase 
== Office Depot ==
Really Useful Box 9L x 6 (delivered)
Really Useful Box 17L x 5 (ordered 4/4)
Entry  Tue Apr 5 18:14:55 2016, Koji, General, Loan / Lending, QPD Lending Crackle 

QPD head
X-Z stage
Entry  Thu May 30 15:00:28 2013, Koji, Optics, General, QPD alignment 
The QPD alignment was adjusted using the aligned beam to the cavity and the 4ch transimpedance amplifier.
As I have a test cable for the QPD, I attached a DB9 connector on it so that I can use the QPD transimpedance
amplifier to read the photocurrent. The transimpedance of the circuit is 1kV/A. 
    Reply  Fri May 31 05:46:54 2013, Koji, Optics, General, QPD alignment QPD1.JPGQPD2.JPGQPD_calib.nb.zip
Peter F suggested to check the bottom surface of the PD housings if there is any protrusion/interference/whatever.
And that was true! It was found that the front side of QPD1 (Left) was lifted by a machining burr.
It seems that this burr consistently exists as the other one also have it (see QPD2 picture (right)) although it is not too terrible compared to
Entry  Tue Oct 15 18:50:08 2013, Koji, Optics, Characterization, QPD alignment 
1) Deburr the bottom surfaces of the QPD housings
2) Aligned the QPDs
Entry  Wed Apr 17 07:30:04 2013, Koji, Optics, General, QPD path glued 
Yesterday, all of the glass components for the QPD path were glued.

- Check the alignment of the beam with the cavity.
Entry  Mon Aug 10 02:11:47 2015, Koji, Electronics, AM Stabilized EOM Driver, RF AM Measurement Unit E1500151 IMG_20150803_223403975.jpgIMG_20150803_221210816_HDR.jpgIMG_20150803_223420267.jpg
This is an entry for the work on Aug 3rd.

LIGO DCC E1500151

Power supply check
    Reply  Mon Aug 10 11:39:40 2015, Koji, Electronics, AM Stabilized EOM Driver, RF AM Measurement Unit E1500151 
Entry for Aug 6th, 2015

I faced with difficulties to operate the RF AM detectors.

I tried to operate the RF AM detector. In short I could not as I could not remove the saturation of the MON outputs, no matter how jiggle the
    Reply  Mon Aug 10 11:57:17 2015, Koji, Electronics, AM Stabilized EOM Driver, RF AM Measurement Unit E1500151 screen_shot.png
Spending some days to figure out how to program CPLD (Xilinx CoolRunner II XC2C384).

I learned that the JTAG cable which Daniel sent to me (Altium JTAG USB adapter) was not compatible with Xilinx ISE's iMPACT.

I need to use Altium to program the CPLD. However I'm stuck there. Altium recognizes the JTAG cable but does not see CPLD. (Attachment 1)
    Reply  Mon Aug 10 12:09:49 2015, Koji, Electronics, AM Stabilized EOM Driver, RF AM Measurement Unit E1500151 IMG_20150809_215628585_HDR.jpg
Still suffering from a power supply issue!

I have been tracking the issues I'm having with the RF AM detector board.

I found that the -5V test point did not show -5V but ~+5V! It seemed that this pin was not connected to
    Reply  Fri Aug 28 02:14:53 2015, Koji, Electronics, AM Stabilized EOM Driver, RF AM Measurement Unit E1500151 ~ 37MHz OCXO AM measurement OCXO_AM_noise.pdf
In order to check the noise level of the RFAM detector, the power and cross spectra for the same signal source
were simultaneously measured with the two RFAM detectors.

As a signal source, 37MHz OCXO using a wenzel oscillator was used. The output from the signal source
    Reply  Tue Sep 8 10:55:31 2015, Koji, Electronics, AM Stabilized EOM Driver, RF AM Measurement Unit E1500151 ~ 37MHz OCXO AM measurement 
Test sheet: https://dcc.ligo.org/LIGO-E1400445

Test Result (S1500114): https://dcc.ligo.org/S1500114
    Reply  Fri Aug 28 01:08:14 2015, Koji, Electronics, AM Stabilized EOM Driver, RF AM Measurement Unit E1500151 ~ Calibration RFAM_detector_calib.pdfRFAM_detector_calib_spectra.pdf
Worked on the calibration of the RF AM Measurement Unit. 

The calibration concept is as follows:

Generate AM modulated RF output
Measure sideband amplitude using a network anayzer (HP4395A). This gives us the SSB
Entry  Wed Aug 29 11:06:30 2018, Koji, General, General, RF AM RIN and dBc conversion 
0. If you have an RF signal whose waveform is , the amplitude is constant and 1.

1. If the waveform 
    Reply  Wed Jul 22 10:15:14 2015, Koji, Electronics, AM Stabilized EOM Driver, RF test of the EOM/AOM Driver S1500117 
7) Make sure the on/off RF button works,
=> OK

8) Make sure the power output doesn't oscillate,
    Reply  Sat Jul 25 17:24:11 2015, Koji, Electronics, AM Stabilized EOM Driver, RF test of the EOM/AOM Driver S1500117 7x
(Calibration for Attachment 5 corrected Aug 27, 2015)

Now the test procedure fo the unit is written in the document https://dcc.ligo.org/LIGO-T1500404

And the test result of the first unit (S1500117) has also been uploaded to DCC https://dcc.ligo.org/LIGO-S1500117
    Reply  Tue Jul 28 18:36:50 2015, Koji, Electronics, AM Stabilized EOM Driver, RF test of the EOM/AOM Driver S1500117 IMG_20150727_214536773_HDR.jpgEOM_Driver_DAQ_TF_test.pdfEOM_Driver_Mon_PSD.pdf
Final Test Result of S1500117: https://dcc.ligo.org/LIGO-S1500117

After some staring the schematic and checking some TFs, I found that the DAQ channels for MON2 have a mistake in the circuit.
Differential driver U14 and U15 of D0900848 are intended to have the gain of +10 and -10 for the pos and neg outputs.
    Reply  Mon Nov 19 13:33:14 2012, Koji, Optics, Characterization, Resuming testing mirror RoCs Cav_scan_response_zoom_20121016.pdf
In order to resume testing the curvatures of the mirrors, the same mirror as the previous one was tested.
The result looks consistent with the previous measurement.
It seems that there has been some locking offset. Actually, the split peaks in the TF@83MHz indicates 
Entry  Fri Oct 5 03:39:58 2012, Koji, Optics, General, RoC Test setup RoC_test_setup.pdfRoC_test_setup.png
Based on Zach's experiment design, I wrote up a bit more detailed optical layout for the mirror test.
Entry  Fri Jun 29 11:26:04 2012, Zach, Optics, Characterization, RoC measurement setup RoC_measurement_setup.pngRoC_measurement_setup.graffle.zip
Here is the proposed RoC measurement setup. Koji tells me that this is referred to as "Anderson's method".
We would like to use a linear cavity to measure the RoC of the curved mirrors independently (before forming the ring cavity), since the degeneracy
of HOMs will make the fitting easier.
    Reply  Sun Jul 22 15:56:53 2012, Zach, Optics, Characterization, RoC measurement setup detailed_RoC_setup.pngdetailed_RoC_setup.graffle.zip
Here is a more detailed version of the setup, so that we can gather the parts we will need.
Entry  Wed Oct 17 20:36:04 2012, Koji, Optics, General, RoC test cavity locked detailed_RoC_setup.pdfomc_cav_lock_SCRN_SHOT.pngCav_scan_response_20121016.pdf
The RoC test setup has been built on the optical table at ATF.

The cavity formed by actual OMC mirrors have been locked.
Entry  Mon Aug 13 16:59:11 2012, Koji, Clean, General, Room Cleaning Log 
Floor wiped with a wet wiper (Aug 13, 2012)
Floor wiped with a wet wiper (Aug 15, 2012)
Floor wiped with a wet wiper (Sep 25, 2012)
Entry  Tue Jan 22 17:56:32 2013, Koji, Mechanics, General, Rotary stage selection 
Newport UTR80

    Sensitivity: 4 arcsec
    Graduations: 1 deg
    Vernier: 1 arcmin
    Fine travel range: 4 deg
Entry  Thu May 20 17:03:50 2021, Koji, General, General, SRS LCR meter SRS720 borrowed from Downs P_20210520_154841.jpg
Item loan: SRS LCR meter SRS720 borrowed from Downs. The unit is at the 40m right now for testing with an excelitas PD. Once it is done, the setup will
be moved to the OMC lab for testing the high QE PDs
    Reply  Fri Jul 22 17:41:01 2022, Koji, General, General, SRS LCR meter SRS720 returned to Downs PXL_20220723_002330805.jpg
SRS LCR meter SRS720 was returned to Downs as before.

Entry  Mon Jul 1 12:49:42 2019, Koji, Optics, Characterization, Scattering measurement of A and C mirrors omc_cm_tis_062419.pdfomc_prism_tis_062419.pdf
Liyuan's scattering measurement for the A and C mirrors.
Entry  Mon Nov 7 21:16:16 2022, Camille, Optics, Configuration, Setting up the fiber couplers PXL_20221108_003849213.jpgPXL_20221108_003909265.jpgPXL_20221108_003929309.jpg
[Camille, Koji]

Began setting up fiber assembly for OMC testing:
-Aligned fiber mount to maximize transmission through fiber
    Reply  Mon Nov 7 22:00:33 2022, Koji, Optics, Configuration, Setting up the fiber couplers 
Fiber matching: 43.2/56.7 = 76%
S/P-pol ratio 0.7/43.2 = 1.6%

Entry  Mon Apr 22 09:54:21 2019, Joe, General, , Shortening cavity (A5,A14,PZT11,PZT22) to get closer to design FSR CM1_IMG_7699.jpgCM2_IMG_7697.jpg

in units 20um per div on the micrometer [n.b. we reailised that its 10um per div on the micrometer]

CM1 inner screw pos: 11.5
Entry  Thu Nov 8 19:47:55 2012, Koji, Electronics, Configuration, Solder for PZTs 
Rich saids:
I have ordered a small roll of solder for the OMC piezos. 
Entry  Mon Dec 31 03:10:09 2012, Koji, Optics, General, SolidWorks model of the OMC breadboard D1201439_aLIGO_Breadboard_layout_assy_121224.pngD1201439_aLIGO_Breadboard_layout_assy_130105.easm
Entry  Sun Jan 6 23:22:21 2013, Koji, Mechanics, General, SolidWorks model of the OMC suspension  D0900295_AdvLIGO_SUS_Output_Mode_Cleaner_Overall_Assembly.pngD0900295_AdvLIGO_SUS_Output_Mode_Cleaner_Overall_Assembly.easm
Entry  Sat Jul 1 21:33:18 2017, Koji, General, General, Some purchase notes 
- Forgot to close the cylinder valve...

v HEPA prefilter (20"x20"x1" MERV 7)

- Replace the filter for the air conditioning
Entry  Wed Jun 5 18:19:51 2013, Koji, General, General, Some recent photos from the OMC final test at CIT 
Applying First Contact for the optics cleaning
Entry  Mon Jul 21 01:02:43 2014, Koji, Mechanics, Characterization, Some structual mode analysis 6x
Fundamental: 12.3kHz Secondary: 16.9kHz
Entry  Mon May 6 19:31:51 2013, Koji, Optics, Characterization, Spot position measurement on the diode mounts DCPD1.pngDCPD2.pngQPD1.pngQPD2.png
Measurement Order: DCPD2->DCPD1->QPD1->QPD2
DCPD1: 1.50mm+0.085mm => Beam 0.027mm too low
DCPD2: 1.75mm+0.085mm => Beam 0.051mm too high (...less confident)
    Reply  Wed May 8 15:08:57 2013, Koji, Optics, Characterization, Spot position measurement on the diode mounts DCPD1.pngDCPD2.pngQPD1.pngQPD2.png
Remeasured the spot positions:
DCPD1: 1.50mm+0.085mm => Beam 0.084mm too high
DCPD2: 1.50mm+0.085mm => Beam 0.023mm too high
Entry  Tue Aug 27 17:02:31 2013, Koji, Mechanics, Characterization, Spot position measurement on the diode mounts DCPD1.png
After the PZT test, the curved mirrors were aligned to the cavity again.
In order to check the height of the cavity beam, the test DCPD mount was assembled with 2mm shim (D1201467-3)
The spot position was checked with a CCD camera.
Entry  Mon Mar 3 02:46:21 2014, Koji, General, Characterization, Spot positions scanned 
Spot positions on CM1 and CM2 scanned according to the recipes provided by the previous entry.
The best result obtained was:
Transmission from FM2: 32.7mW
    Reply  Fri Sep 13 15:09:20 2013, Koji, General, General, Sprinkler installation: done P9134379.jpgP9134378.jpg
A sprinkler head was installed on the HEPA enclosure. The head is covered with a plastic cap.
    Reply  Tue Sep 9 20:59:19 2014, Koji, Mechanics, Characterization, Structural mode analysis for the PZT mirror 6x
Structural analysis of the PZT mirror with COMSOL.
Inline figures: Eigenmodes which involves large motion of the tombstone. In deed 10kHz mode is not the resonance of the PZT-mirror joint,
but the resonance of the tombstone.
Entry  Sat Feb 2 16:17:13 2019, Koji, Optics, Characterization, Summary: OMC(001) HOM structure recalculation OMC_HOM_130531.pdfHOM_PZTV.pdfHOM_plot_PZT0_0.pdfCav_scan_response_HOM.pdf
Each peak of the transfer function measurement was fitted again with a complex function:

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