40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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Entry  Mon Aug 10 15:34:04 2020, Koji, Facility, Loan / Lending, Glue bake oven 

Black and Decker Glue Baking Oven came back to the OMC lab on Aug 10, 2020, Georgia had lent the unit for the SAMS assembly/testing.

Entry  Fri Aug 30 12:14:50 2013, Koji, Optics, General, H1 OMC Cavity length adjustment Gouy_FSR_130827.nb.zipP8284343.jpg

Short conclusion:

The roundtrip cavity length for the H1 OMC was adjusted to be 1.145m
instead of 1.132m such that the 19th HOMs of the lower sideband do not get resonant together with the carrier.


Background:

The purpose of the OMC is to transmit the carrier TEM00 mode while anything else is rejected.
As the optical cavity has infinite numbers of resonant modes, what we practically do is to select
the roundtrip accumulated gouy phase so that low order higher order modes for the carrier
as well as the sidebands (including the TEM00 modes).

The nominal round trip length of the OMC is 1.132m. The curvature of the mirror is 2.575m.
The nominal ratio between the TMS and FSR is 0.218791 and 0.219385 (TMS_V/TMS_H= 0.9973)
for the vertical and horizontal modes. This split comes from the non-zero angle (~4deg) of incidence on the curved mirrors.

In reality, the TMS/FSR ratio depends on the true curvature of the mirror. More importantly, astigmatism
of the mirror changes the difference of the ratios for the vertical and horizontal modes.

The mirror astigmatism can either reduce or increase the split. between the TMSs. For example,
the L1 OMC showed the TMS/FSR ratio of (0.218822, 0.219218) for the vertical and horizontal modes.
TMS_V/TMS_H is 0.9982 which is 0.18% from the unity. This suggests, roughly to say, that 0.27% of the
astigmatism coming from the AOI of 4deg was partially compensated by the mirror astigmatism. This was lucky.

Something unlucky happened to the case for the first choice of the H1OMC curved mirrors.
TMS_V/TMS_H is 0.990 which is indeed 1% away from the unity. This actually caused some problem:
As the modes spreads too wide, the 19th modes became unavoidable. (see the picture below)

           Red - carrier, Blue - upper sideband (+45MHz), Green - lower sideband

After the replacing one of the PZT assembly with another one, 1-TMS_V/TMS_H went down to 6%.
But still the 19th mode is on resonance. In order to shift the 19th mode from the resonance, the cavity length
had to be changed more than the range of the micrometer.

Simple simulation:

Attached Mathematica file calculates expected mode structure when the curved mirror position is
moved by DL (then the total roudtrip length changes 4*DL). This tells us that the 19th mode is
moved from the resonance by giving DL=-0.003 or DL=0.0025.

It was impossible to make the cavity short enough as the gluing fixture interferes with the curved mirror.
In fact, it was also impossible to make the cavity long enough as it was. Therefore PEEK shims with
the thickness of 1.5mm was inserted.

P8284343.jpg

Result:

The FSR and TMS were measured with the longer cavity. 50V was applied to PZT1.

FSR: 261.775MHz
TMS_V: 57.575MHz
TMS_H: 57.880MHz

=> Cavity round trip length of 1.1452m
=> TMS/FSR = {0.219941, 0.221106}

The 19th modes for the lower sidebands are successfully moved from the carrier resonance.
The first accidental resonance is the lower sideband at the 28th order modes.

Entry  Fri Aug 30 12:22:56 2013, Koji, Optics, General, H1 OMC Cavity side UV gluing 

H1 OMC Cavity side optics was glued on the breadboard

Curved mirror gluing

- Applied the UV glues to CM1/CM2 prisms.

- Checked the spot positions on the curved mirrors

- Apply 50V to CM1

- Measure the FSR and TMS while the cavity was locked.

FSR: 261.70925MHz
TMS_V: 57.60500MHz
TMS_H: 57.94125MHz

=> Cavity round trip length of 1.1455m
=> TMS/FSR = {0.220111, 0.221395}

First accidental resonance is the lower sideband at 28th order modes.

Carrier 9th-order HOM: 2.9~7.6 line width away
Upper Sideband 13th-order HOM: 14.1-20.7 LW away
Lower Sideband 19th-order HOM: 3.3-13.1 LW away

- As this result was satisfactory, the UV illumination was zapped. It did not change the alignment. The cavity was kept locked during the illumination.

Peripheral optics gluing

- QPD path BS/Steering Mirrors were glued
- DCPD path BS was glued

The UV glue was applied to the optics.
Then the optics were placed on the breadboard along with the fixture.

Placed the dummy QPD/DCPD mount with the alignment disks.
The horizontal positions of the spots were well with in the horizontal range of the mounts.
 The UV illumination was zapped. Checked the alignment again and no problem was found.

Entry  Fri Aug 12 14:58:17 2016, Koji, General, Configuration, H1 OMC DCPD replacement  

Preparation of 3rd OMC for the use in H1

New DCPD(T) = B1-01
DCPD(T) = DCPDA: extracted and accomodated in CAGE-A SLOT1

New DCPD(R) = B1-16
DCPD(R) = DCPDB: extracted and accomodated in CAGE-A SLOT2

Entry  Fri Aug 30 12:25:29 2013, Koji, General, General, H1 OMC Invar mount gluing P8304368.JPGP8304370.JPG

The Invar Mounting Blocks were glued on the breadboard.

Serial number #1/2/5/6/7/8 -> I1 OMC cable side

Serial number #9/10/11/12 -> H1 OMC cavity side

Entry  Mon Oct 14 13:40:16 2013, Koji, Optics, Characterization, H1 OMC Optical testing 

Since the middle of September, the optical tests of H1 OMC were took place.
Here is summary of the progress.

TEST1: FSR/FINESSE measurement before applying First Contact
TEST2: Power budget

MIrror cleaning with First Contact

TEST3: FSR/FINESSE measurement after First Contact application
TEST4: Power budget

TEST5: N/A

TEST6: HOM measurement @PZT V=0
TEST7: HOM measurement @PZT V=0-200

TEST8: DC response of the PZT
TEST9: AC response of the PZT

TEST10: PD/QPD alignment / output check

 

 

Entry  Mon Oct 14 15:50:55 2013, Koji, Optics, Characterization, H1 OMC Power budget OMC_power_budget.pdf

LHO OMC power budget

Date 2013/9/17 2013/9/17 2013/10/16 2013/10/22
Condition  Before the cleaning  After the cleaning  Confirmation  Confirmation
Input Power [mW]  35.2  35.4  34.54  34.9
REFLPD dark offset [V]  -0.00763  -0.00763  -0.00772  -0.000759
REFLPD unlocked [V]  0.0749 +/- 0.0005  0.067+/- 0.0005  0.0640+/-0.0005  0.0530+/-0.0001
REFLPD locked [V]  5.49 +/- 0.01  5.55+/-0.01  5.28+/-0.01  5.26+/-0.01
         
 Transmitted Power to DCPD1 (T) [mW]  16.5  16.4  16.1  16.0
 Transmitted Power to DCPD2 (R) [mW]  15.9  16.2  15.55  15.55
 FM2 transmission [mW]  32.4  32.9+/-0.1  -  -
 CM1 transmission [mW]  0.166  0.169  0.164  0.165
 CM2 transmission [mW]  0.165  0.169  0.158  0.162
 Input BS transmission [mW]  0.234  0.218  0.230  0.227
         
 Cavity Finesse  373.114  373.114  373.114  373.114
         
 Junk Light Power (Pjunk) [mW]  0.489  0.434  0.422  0.332
 Coupled beam power (Pcouple) [mW]  34.71  34.97  34.12  34.57
 Mode Matching (Pcouple/Pin) [mW]  0.986  0.988  0.988  0.990
 Cavity reflectivity in power  0.00115  0.00119  0.00136  0.00199
 Loss per mirror [ppm]  122  124  134  167
 Cavity transmission for TEM00 carrier
 0.933  0.932  0.927  0.913

 

Entry  Wed Aug 21 08:31:21 2013, Koji, Optics, Characterization, H1 OMC cavity alignment 

Alignment of the H1 OMC cavity mirrors

- The cavity mirrors as well as the first steering mirror were aligned on the cavity side template.

- The locking of the cavity was not so stable as before. Some high freq (several hundreds Hz) disturbance makes the cavity
  deviate from the linear range. This can be mitigated by turning off the HEPA units but this is not an ideal condition.

- FSR and TMS were measured.

FSR: 264.305MHz
TMS(V): 58.057MHz
TMS(H): 58.275MHz

These suggest the cavity length L and f_TMS/f_FSR (say gamma, = gouy phase / (2 pi) ) as
L=1.1343 m        (1.132m nominal)
gamma_V = 0.219659    (0.21879 nominal)
gamma_H = 0.220484    (0.21939 nominal)


- the 9th modes of the carrier is away from the resonance 6-9 times of the line width (LW)
- the 13th modes of the lower f2 sideband are 11-15 LW away
- the 19th modes of the upper f2 sideband are 0.6-7 LW away

We still need precise adjustment of the gouy phase / cavity length, this was enough for the gluing of the flat mirrors

Entry  Tue Sep 3 17:03:25 2013, Koji, General, General, H1 OMC gluing completed 

[Koji Jeff]

H1 OMC All Gluing completed

5 Glue H1 beam dumps (UV)

4 glass wire brackets glued on the H1 topside (UV) SN: #9/10/11/12

6 Invar blocks glued on the H1 topside (EP30) SN: #13/14/15/16/18/19

Entry  Wed Sep 4 22:22:54 2013, Koji, General, General, H1 OMC wrapped and moved to the bake lab. 

[Koji, Jeff]

We moved the H1OMC to the bake lab.

Chub set up the vacuum bake oven (Oven F) and running without the actual OMC.

We use low temperature (55degC) for the baking.

The actual OMC will be baked from tomorrow afternooon.

Entry  Thu Aug 29 02:52:50 2013, Koji, Optics, Characterization, H1OMC Curved Mirror Alignment Cav_scan_response_130828_Pitch.pdfCav_scan_response_130828_Yaw.pdf

Cavity parameter was measured with 50V bias on PZT1 (CM1)

- PZT combination was changed: PZT1 #21 (PZT ASSY#6) / PZT2 #25 (PZT ASSY #4)

- 19th HOMs of the USB makes accidental resonance with the nominal cavity length.
  Because of the mirror astigmatism, HOMs spreads more than the design.
  In order to avoid these modes, the cavity length had to be moved from the nominal value (1.134m).

- The clearance between the fixture and the prism was limited. This prevents to shorten the cav length.
  The cavity length was made longer about 10mm.

-----

Cavity parameter obtained from the pitch misalignment

Free Spectral Range (FSR): 261.777947 +/− 0.000299 MHz
Cavity roundtrip length: 1.145217 +/− 0.000001 m
Lock offset: 1.636183 +/− 0.238442 kHz
Transverse mode spacing (TMS): 57.581950 +/− 0.000163 MHz
TMS/FSR: 0.219965 +/− 0.000001
Cavity pole (1st order modes, avg and stddev): 353.465396 +/− 0.657630 kHz
Finesse (1st order modes, avg and stddev): 370.302940 +/− 0.688585

Carrier 9th-order HOM: -8.1 line width away
Upper Sideband 13th-order HOM: 13.3 LW away
Lower Sideband 19th-order HOM: 2.2 LW away

-----

Cavity parameter obtained from the pitch misalignment

Free Spectral Range (FSR): 261.777106 +/− 0.000226 MHz
Cavity roundtrip length: 1.145220 +/− 0.000001 m
Lock offset: 0.215937 +/− 0.183434 kHz
Transverse mode spacing (TMS): 57.875622 +/− 0.000116 MHz
TMS/FSR: 0.221087 +/− 0.000000
Cavity pole (1st order modes, avg and stddev): 356.862001 +/− 0.448102 kHz
Finesse (1st order modes, avg and stddev): 366.776766 +/− 0.460598

Carrier 9th-order HOM: -4.1 line width away
Upper Sideband 13th-order HOM: 19.1 LW away
Lower Sideband 19th-order HOM: 10.8 LW away

-----

We could avoid hitting the 19th modes of the 45MHz sidebands.

First accidental hit is the 28th order modes of the lower sideband.

Red: Carrier
Blue: Upper sideband (45MHz)
Green: Lower sideband (45MHz)

Entry  Mon Nov 4 19:43:56 2013, Koji, General, General, H1OMC Packed 

H1OMC PZT connector was replaced with the correct one. This was the final step for H1OMC.

Jeff and I packed the OMC and put it in the perikan case. It will be shipped tomorrow.

The other tools are also packed in the other box. Here is the list of the items

- Spare PD/QPDs (2 cages)
- Test PD/QPD cables
- Torque driver / bits
- Low noise transimpedance amp
- Kapton sheets
- First Contact kit
- 1/4-20 Screws for the balance weights
- OMC-Structure cables
- Preamp adapter plate
- Screws for the cable mounts
- Clean tools
  (scissors, tweezers, forceps, Diagonal pliers, long nose prier)
- Spare Peek cable ties
Entry  Fri Aug 30 12:24:28 2013, Koji, Optics, Characterization, H1OMC Spot positions DCPD1.pngDCPD2.pngQPD1.pngQPD2.png

Beam heights on the diodes

DCPD1: 14.459mm -> With 1.5mm shim, the beam will be 0.038mm too low.

DCPD2: 14.221mm -> With 1.25mm shim, the beam will be 0.026mm too low.

QPD1: 14.691mm -> With 1.75mm shim, the beam will be 0.056mm too low.

QPD2: 14.379mm -> With 1.5mm shim, the beam will be 0.118mm too low.

Entry  Tue Oct 22 17:17:59 2013, Koji, General, General, H1OMC cabling 

[Chub, Jeff, Koji]

We worked on the wiring and routing of the cables.

- The cables for the PZT was installed first.

- Pins for the mighty mouse connector were crimped on the PZT wires

- Checked the wiring diagram (D1300589) to find the pinouts.
  Pin1 of the mighty mouse is connected to PZT2+, Pin2 to PZT2-, PIn3 to PZT1+, and Pin4 to PZT1-

- Then QPD and PD cables are fixed on the cable harness.

- The QPD/PD cables are attached on the diode housings.

During this process one of the DCPD mounts moved. The fixing screws were not torqued enough.
This means that all of the FC layers need to be removed and the DCPD housing should be aligned again.

- We continued on the cabling. The cables were routed on the top (cable) side.

- Some of the cable pegs were tightened by PEEK cable ties.

- We found that Pin1 and Pin2 of the PZT cables were not intact anymore.

- We ask Chub to work on the PZT pins tomorrow. The PD alignment will be taken tonight or tomorrow.

Entry  Thu Nov 21 00:05:35 2013, Koji, General, General, H1OMC electronics arrangement H1OMC_cable_arrangement.pdf

Checked the PZT arrangement: Mighty Mouse Pin1&2 -> PZT2 (DCPD side), Mighty Mouse Pin3&4 -> PZT1 (QPD side)

DCPD response:
Illuminate DCPD1 (T) -> DCPD B responded in MEDM
Illuminate DCPD2 (R) -> DCPD A responded in MEDM

QPD response:
Illuminate QPD1 -> QPD A responded in MEDM
Illuminate QPD2 -> QPD B responded in MEDM

--------

DCPD1 (T) is marked as "A". This PD is SN"0288"

DCPD2 (R) is marked as "B". This PD is SN"0721"

Corresponding iLOG for the performance

Entry  Mon Jun 24 12:54:58 2019, Koji, Clean, General, HEPA BOOTH 

https://www.airscience.com/purair-flow-laminar-flow-cabinets

Entry  Sun Jul 6 03:56:40 2014, Koji, Optics, Characterization, HOM measurement with PZT vol swept Cav_scan_response_PZT1.pdfCav_scan_response_PZT2.pdfOMC_HOM_140705.pdf

Cavity FSR/TMS measurement (2014/7/5) with PZT voltages swept from 0V to 200V (50V step)

    Reply  Sun Jul 6 08:31:14 2014, Koji, Optics, Characterization, HOM measurement with PZT vol swept HOM_plot.pdf

3rd OMC, HOM diagram at PZT1=0V and PZT2=50V.

First coincidence with the carrier is the 32nd-order carrier mode. Very good.

Entry  Sat Mar 26 01:49:48 2016, Koji, Optics, Characterization, HQEPD QE QE1.pngQE2.png

Calibration of the transimpedance

Use KEITHLEY 2450 as a calibrated current source. Model 2450 has the current source accuracy of 0.020%+1.5uA at 10mA range. For 6mA current output, the error is 3uA (0.05%).

The output of the current amp at 103 Ohm setting was 6.0023V when -6.000mA current was applied. i.e R_trans = 1000.4 +/- 0.5 Ohm. This is a negligible level.

QE of the diodes (As of 07/30/2016)

Refer E1800372

Entry  Sun Mar 13 22:02:09 2016, Koji, Optics, Characterization, HQEPD QE measurement (direct comaprison) 

Direct comparison of the PD responsibities

We can expect 5% increase of the QE with the new PD.


P-pol 10deg incident

Power meter Ophir RM9C (Systematic error +/-5%)
Vbias = 6V

C30665GH (#07)
Incident: 7.12mW
Reflection: 0.413mW (=> R=5.8%)
PD output: 5.690+/-0.006V
=> Responsibity 0.799+/-0.001 A/W
=> QE = 0.931+/-0.001

HQE PD (A1-23)
Incident: 7.15mW
Reflection: 0.020+/-0.1mW (=> R=0.28%)
PD output: 6.017+/-0.007V
=> Responsibity 0.842+/-0.001 A/W
=> QE = 0.981+/-0.001

Note that there is a 5% systematic error with the power meter.

Entry  Sat Mar 26 17:39:50 2016, Koji, Electronics, Characterization, HQEPD dark noise PD_dark_current.pdf

Dark noise measurement for 6 HQEPDs and 1 C30665. All of these showed sufficiently low dark current noise levels compared with the noise level of the DCPD preamp. The measurement was limited by the input noise (ADC) noise of the FFT analyzer as the line noises were too big.

The measurement has been done with the transimpedance of 1e7. The bandwidth of the measurement was 50kHz.

Entry  Fri Jul 22 22:24:05 2016, Koji, General, General, HQEPD inventory 

As of Jul 22, 2016
As of Aug 11, 2016

As of Aug 16, 2016


A1-23 in Cage G https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-A1-23
-> Shipped to LLO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8181
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-1
= Replaced C30665 eLIGO PD (SN 01 in Cage G now) ICS: C30665GH-0-00-0001
-> Removed PD@LLO, Waiting for the shipment to CIT

A1-25 in Cage G https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-A1-25
-> Shipped to LLO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8181
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-1
= Replaced C30665 eLIGO PD (SN 02 in Cage G now) ICS: C30665GH-0-00-0002
-> Removed@LLO, Waiting for the shipment to CIT


B1-01 in Cage A https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-B1-01
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-3_2
= replaced C30665 eLIGO PD (SN 11 in Cage A now) ICS: C30665GH-0-00-0011
-> Removed PD@LHO
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8187

B1-16 in Cage A https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-B1-16
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-3_2
= replaced C30665 eLIGO PD (SN 12 in Cage A now) ICS: C30665GH-0-00-0012
-> Removed PD@LHO
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8187


C1-05 in Cage F https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-05
-> @CIT contamination test cavity

C1-07 in Cage F https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-07
-> @CIT contamination test cavity


C1-17 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-17
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Left @LHO as a spare

C1-21 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-21
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Left @LHO as a spare


D1-08 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-D1-08
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Moved to Cage A3
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8186
-> Arrived at CIT (Aug 16)

D1-10 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-D1-10
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Moved to Cage A4
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8186
-> Arrived at CIT (Aug 16)

    Reply  Tue Jul 26 00:12:58 2022, Koji, General, General, High QE PD: QE measurements IMG_1118.JPG

- Installed the High QE PDs to OMC #002

  • B1-22@Cage B1 was installed to the transmission DCPD
  • B1-23@Cage B1 was installed to the reflection DCPD

Upon the installation, the legs of the PDs were cut by 3mm. Also, the tab of the PD could not be embedded in the DCPD housing. Therefore, the tabs were cut.

The alignment looked just fine. The weak reflections are directed to the black glass beam dumps.

- After the installation, the QEs were measured.

  • With Thorlabs S130C power meter, the QE was estimated to be ~95%. (Accuracy +/-7%)
  • With Thorlabs S401C power meter, the QE was estimated to be ~100%. (Accuracy +/-3%)

It is so confusing. So I decided to make the QE test setup.


Ophir RM9 with chopper (+/-5%): 8.97mW
Thorlabs S140C integrating sphere (+/-7%): 9.11mW
Thorlabs S130C PD power meter (+/-7%): 9.15mW
Thorlabs S401C thermal power meter (+/-3%): 8.90mW
So there looks ~3% discrepancy between S130C and S401C

Then tried to measure the QE of C1-03@Cage B3 with Ophir RM9
- Initial state: QE=0.95
- First FirstContact application: QE went up to 0.973
- Second FirstContact application: QE = 0.974, basically no change


To Do:
- Calibrate the trans-impedance amp with Keithley
- Apply FC to B1-22 and B1-23 to see if there is an improvement
- The power should be measured with S401C because the accuracy seems better (+/-3%).
- Take photos of the PD FC process

General To Do:

- Backscatter test 2nd trial

- Start applying the first contact to the optical surfaces
- Beam dump cleaning
- Apply FC cap to the PDs
- Delamination repair (light side)
- Delamination repair (dark side)
- Cable bracket replace (dark side)

 

    Reply  Wed Jul 27 10:34:09 2022, Koji, General, General, High QE PD: QE measurements 2 IMG_1119.JPGIMG_1120.JPG

- DLPCA-200 trans-impedance amplifier was calibrated.
  Keithley source meter 2450 was connected to the amp. Provide current and read the output voltage with the precision digital voltage meter (Agilent/Keysight).
  Gain: 999.7V/A@7mA, 999.6V/A@8mA

- From the power meter spec, Thorlabs S401C seemed the best (+/-3%). So the QEs of the 9 PDs were checked with this power meter again.

- All PDs exhibited the QE of 0.95~0.96. It's all relative as the power meter has a systematic error.
- Tried to clean B1-22 and B1-23 PDs. They didn't show significant improvement after the cleaning. To avoid the unnecessary risk of damaging the PDs, further cleaning was not performed. (Some photos were attached)

- What we can do is use this result as the relative measurements.
- For OMC#2, B1-22 is the DCPD(T) and B1-23 is the DCPD(R). C1-03 and C1-12 are the spares, according to this latest result.
- At LLO, we track down the source of the throughput reduction (-10%). The QEs of the PDs are going to be tested in the same setup at once to compare their PDs and our PDs.

PD Type SN Case DCV1 Pin [mW] dPin [mW] Power Meter DCV2 Avg(DCV) Std(DCV) DCVOFS (mV) Responsivity [A/W] dR QE dQE Date Note
IGHQEX3000 B1-22 B1 7.734 9.43 0.02 TL 401C 7.745 7.7395 0.006 -0.0260 0.821 0.002 0.957 0.002 July 26, 2022 clean1 / installed (T)
IGHQEX3000 B1-23 B2 7.679 9.26 0.02 TL 401C 7.709 7.6940 0.015 -0.0220 0.831 0.002 0.969 0.003 July 26, 2022 clean1 / installed (R)
IGHQEX3000 C1-03 B3 7.775 9.40 0.02 TL 401C 7.770 7.7725 0.003 -0.0450 0.827 0.002 0.964 0.002 July 26, 2022 clean3
                                 
IGHQEX3000 C1-08 C2 7.717 9.45 0.02 TL 401C 7.750 7.7335 0.017 -0.0430 0.819 0.002 0.954 0.003 July 26, 2022 initial
IGHQEX3000 C1-09 C3 7.737 9.50 0.05 TL 401C 7.776 7.7565 0.019 -0.0580 0.817 0.005 0.952 0.006 July 26, 2022 initial
IGHQEX3000 C1-10 C4 7.757 9.50 0.03 TL 401C 7.774 7.7655 0.009 -0.0650 0.818 0.003 0.953 0.003 July 26, 2022 initial
                                 
IGHQEX3000 C1-11 D1 7.826 9.66 0.01 TL 401C 7.828 7.8270 0.001 -0.0570 0.810 0.001 0.945 0.001 July 26, 2022 initial
IGHQEX3000 C1-12 D2 7.841 9.51 0.02 TL 401C 7.841 7.8410 0.000 -0.0410 0.825 0.002 0.961 0.002 July 26, 2022 initial
IGHQEX3000 C1-14 D3 7.769 9.55 0.01 TL 401C 7.789 7.7790 0.010 -0.0520 0.815 0.001 0.950 0.002 July 26, 2022 initial
Entry  Wed Jun 20 00:10:53 2012, Koji, Facility, General, Hole on the wall was patched P6191706.jpg

P6191706.jpg

Entry  Thu Nov 8 20:12:10 2012, Koji, Optics, Configuration, How many glass components we need for a plate 

Optical prisms 50pcs (A14+B12+C6+E18)
Curved Mirrors 25pcs (C13+D12)

  Qty

Prisms

Curved No BS OMC Wedge tested
Coating A: IO coupler   14 0  2 prisms 5/5
Coating B: BS 45deg   12 0  2 prisms  0/5
Coating C: HR   6 13 2 curved  
Coating D: Asym. output coupler   0 12 -  
Coating E: HR 45deg   18 0  4 prism (1 trans + 3 refl) 0/3
D1102209 Wire Mount Bracket 25      4  
D1102211 PD Mount Bracket 30      8  

 

Entry  Thu Nov 8 19:52:57 2012, Koji, Optics, General, How to apply UV epoxy UVepoxy.jpg

KA's question:

Do you know how to apply this epoxy?
Do we need a plunger and a needle for this purpose?

Nic saids:

When we did it with Sam, I seem to remember just squirting some on some foil then dabbing it on with the needle.

Entry  Thu Aug 29 18:55:36 2013, Koji, Mechanics, General, I1 OMC top side gluing (UV) 

The glass components for the I1 OMC top side were glued by the UV glue.

Breadboard SN#4
Wire bracket SN#5/6/7/8

Entry  Fri Jul 11 00:06:33 2014, Koji, Optics, Characterization, I1OMC PD 

DCPD#             DCPD1      DCPD2
Housing#          #009       #010
Diode#            #07        #10
Shim              1.00mm 01  1.00mm 02   (1.00mm = D1201467-09)

-------------------------------------
Power Incident     11.1 mW   10.6 mW
Vout                7.65 V    7.33 V

Responsivity[A/W]   0.69      0.69
Q.E.                0.80      0.81
-------------------------------------
photo              2nd        1st

 

PD alignment confirmation

Entry  Thu Jul 10 23:22:28 2014, Koji, Optics, Characterization, I1OMC QPD 

QPD#              QPD1       QPD2
Housing#          #006       #007
Diode#            #50        #51
Shim              1.25mm 03  1.25mm 02   (1.25mm = D1201467-10)

-------------------------------------
Power Incident    123.1-13.0 uW  124.5-8.0 uW
Sum Out            77.0 mV   82.5 mV
Vertical Out      -24.0 mV  - 8.8 mV
Horizontal Out      4.2 mV    9.0 mV
SEG1              -11.6 mV  -16.0 mV
SEG2              -12.6 mV  -18.0 mV
SEG3              -25.2 mV  -24.4 mV
SEG4              -21.4 mV  -21.4 mV
-------------------------------------
Spot position X   -21   um  -19   um  (positive = more power on SEG1 and SEG4)
Spot position Y   +102  um  +47   um  (positive = more power on SEG3 and SEG4)
-------------------------------------

Responsivity[A/W] 0.70      0.71
Q.E.              0.82      0.83
-------------------------------------

Arrangement of the segments
View from the beam
/ 2 | 1 X
|---+---|
\ 3 | 4 /

---------------

I(w,x,y) = Exp[-2 (x^2 + y^2)/w^2]/(Pi w^2/2)

(SEG_A+SEG_B-SEG_C-SEG_D)/(SEG_A+SEG_B+SEG_C+SEG_D) = Erf[sqrt(2) d/w]

d: distance of the spot from the center
w: beam width

Entry  Sat May 17 07:40:14 2014, Koji, Optics, Characterization, I1OMC cavity mirrors glued Cav_scan_response_140516_Pitch.pdfCav_scan_response_140516_Yaw.pdf

I1OMC cavity mirrors were glued.

FSR = 264.82MHz => Lcav = 1.132m (nominal 1.132m)

TMS/FSR for Vpzt1=Vpzt2=0: 0.2185 (V) and 0.2196 (H) (nominal 0.219)

 

aLIGO OMC: Power Budget 2014/5/16

<<<Measured Values>>>
Input Power: 35.7 [mW]
Transmitted Power through FM2: 33.5 [mW]
Transmitted Power through CM1: 0.188 [mW]
Transmitted Power through CM2: 0.192 [mW]
Reflection PD DC output (Unlocked): 6.2 [V]
Reflection PD DC output (Locked): 0.096 [V]
Reflection PD DC output (Dark Offset): -0.00745 [V]
Assumed cavity finesse : 400.

<<<Results>>>
Input Power: 35.7 [mW]
Uncoupled light Power (Junk light + sidebands): 0.575698 [mW]
Input TEM00 Carrier Power: 35.1243 [mW]  (Ratio: 0.983874)
Cavity reflectivity (in power): 548.319 ppm
Cavity transmission (in power): 0.953756
Loss per mirror: 70.1183 ppm
FM1 power transmission: 7640.17 ppm
FM2 power transmission: 7640.17 ppm
CM1 power transmission: 43.2093 ppm
CM2 power transmission: 44.1337 ppm

 

Entry  Thu Jul 17 02:19:20 2014, Koji, Mechanics, Characterization, I1OMC vibration test 6x

Summary

- The breadboard has a resonance at 1.2kHz. The resonant freq may be chagned depending on the additional mass and the boundary condition.

- There is no forest of resonances at around 1kHz. A couple of resonances It mainly starts at 5kHz.

- The PZT mirrors (CM1/CM2) have the resonance at 10kHz as I saw in the past PZT test.


Motivation

- Zach's LLO OMC characterization revealed that the OMC length signals have forest of spikes at 400-500Hz and 1kHz regions.

- He tried to excite these peaks assuming they were coming from mechanical systems. It was hard to excite with the OMC PZT,
but actuating the OMCS slightly excited them. (This entry)

Because the OMC length control loop can't suppress these peaks due to their high frequency and high amplitude, they limit
the OMC residual RMS motion. This may cause the coupling of the OMC length noise into the intensity of the transmitted light.
We want to eventually suppress or eliminate these peaks.

By this vibration test we want to:

- confirm whether the peaks are coming from the OMC or not.
- identify what is causing the peaks if they are originated from the OMC
- correct experimental data for comparison with FEA

Method

- Place a NOLIAC PZT on the object to be excited.
- Look at the actuation signal for the OMC locking to find the excited peaks.

Results

Breadboard

- This configuration excited the modes between 800-1.2kHz most (red curve). As well as the others, the structures above 5kHz are also excited.

- The mode at 1.2kHz was suspected to be the bending mode of the breadboard. To confirm it, metal blocks (QPD housing and a 4" pedestal rod)
  were added on the breadboard to change the load. This actually moved (or damped) the mode (red curve).

- Note that the four corners of the breadboard were held with a PEEK pieces on the transport fixture.
  In addition, the installed OMC has additional counter balance mass on it.
  This means that the actual resonant frequency can be different from the one seen in this experiment. This should be confirmed with an FEA model.
  The breadboard should also exhibit higher Q on the OMCS due to its cleaner boundary condition. 

 

I1OMC_vibration_test_Breadboard.png

DCPD / QPD

- Vibration on the DCPDs and QPDs mainly excited the modes above 3kHz. The resonances between 3 to 5kHz are observed in addition to the ubiquitous peaks above 5kHz.
  So are these coming from the housing? This also can be confirmed with an FEA model.

- Some excitation of the breadboard mode at 1.2kHz is also seen.

 

I1OMC_vibration_test_DCPD.pngI1OMC_vibration_test_QPD.png

CM1/CM2 (PZT mirrors)

- It is very obvious that there is a resonance at 10kHz. This was also seen in the past PZT test. This can be concluded that the serial resonance of the PZT and the curved mirror.
- There is another unknown mode at around 5~6kHz.

- Some excitation of the breadboard mode at 1.2kHz is also seen.

I1OMC_vibration_test_CM.png

FM1/FM2 and Peripheral prism mirrors (BSs and SMs)

- They are all prism mirrors with the same bonding method.

- The excitation is concentrated above 5kHz. Small excitation of the breadboard mode at 1.2kHz is also seen. Some bump ~1.4kHz is also seen in some cases.

I1OMC_vibration_test_FM.png I1OMC_vibration_test_Prism.png

Beam dumps

- The excitation is quite similar to the case of the peripheral mirrors. Some bump at 1.3kHz.

I1OMC_vibration_test_BD.png


Other tapping test of the non-OMC object on the table

- Transport fixture: long side 700Hz, short side 3k. This 3K is often seen in the above PZT excitation

- Fiber coupler: 200Hz and 350Hz.

- The beam splitter for the back scattering test: 900Hz

    Reply  Sun Jul 20 17:19:50 2014, Koji, Mechanics, Characterization, I1OMC vibration test ~ 2nd round 9x

Improved vibration measurement of the OMC

Improvement

- Added some vibration isolation. Four 1/2" rubber legs were added between the OMC bread board and the transport fixture (via Al foils).
  In order to keep the beam height same, 1/2" pedestal legs were removed.

- The HEPA filter at the OMC side was stopped to reduce the excitation of the breadboard. It was confirmed that the particle level for 0.3um
  was still zero only with the other HEPA filter.


Method

- Same measurement method as the previous entry was used.

Results

Breadboard

- In this new setup, we could expect that the resonant frequency of the body modes were close to the free resonances, and thus the Q is higher.
  Noise is much more reduced and it is clear that the resonance seen 1.1kHz is definitely associated with the body mode of the breadboard (red curve).

  As a confirmation, some metal objects were placed on the breadboard as tried before. This indeed reduced the resonant frequency (blue curve).

I1OMC_vibration_test_Breadboard.pngI1OMC_vibration_test_Breadboard_HiRes.png

DCPD / QPD

- Vibration on the DCPDs and QPDs mainly excited the modes above 2~3kHz.
  In order to check if they are coming from the housing, we should run FEA models.

- Some excitation of the breadboard mode at 1.1kHz was also seen.

I1OMC_vibration_test_DCPD.pngI1OMC_vibration_test_QPD.png

CM1/CM2 (PZT mirrors)

- Baseically excitation was dominated by the PZT mode at 10kHz. Some spourious resonances are seen at 4~5kHz but I believe this is associated with the weight placed on the excitation PZT.

I1OMC_vibration_test_CM.png

FM1/FM2 and peripheral prism mirrors (BSs and SMs)

- The modes of the FMs are seen ~8k or 12kHz. I believe they are lowered by the weight for the measurement. In any case, the mode frequency is quite high compared to our frequency region of interest.

- As the prism resonance is quite high, the excitation is directly transmitted to the breadboard. Therefore the excitation of the non-cavity caused similar effect to the excitation on the breadboard.
  In fact what we can see from the plot is excitation of the 1.1kHz body mode and many high frequency resonances.

I1OMC_vibration_test_FM.pngI1OMC_vibration_test_Prism.png

Beam dumps

- This is also similar to the case of the peripheral mirrors.

I1OMC_vibration_test_BD.png

Entry  Tue Jun 24 18:43:15 2014, Koji, General, General, ICS entries for the OMC baking/assembly 

For baking:

  • Assembly Name aLIGO Output Mode Cleaner
    Assembly Number D1201439
     
  • Part Name: Breadboard transport fixture
    Part # / Drawing #: D1201515
     

TO BE ADDED TO THE ASSEMBLY after the bake: [DONE]
803-003-07M6-4PN-598A-0-Bulk-H42Q001
D1201274-V1-00-S009: OMC DCPD Housing        (remove part)
D1201274-V1-00-S010: OMC DCPD Housing        (remove part)
D1201275-V1-00-0006: OMC DCPD FACE PLATE        (remove part)
D1201275-V1-00-0007: OMC DCPD FACE PLATE        (remove part)
D1201280-V1-00-0006: OMC QPD HOUSING        (remove part)
D1201280-V1-00-0007: OMC QPD HOUSING        (remove part)
D1201281-V1-00-0006: OMC QPD FACE PLATE        (remove part)
D1201281-V1-00-0007: OMC QPD FACE PLATE        (remove part)
D1300052-V1-00-0003: aLIGO OMC BRACKET, CABLE CONNECTOR        (remove part)
D1300057-v2-00-0021: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0022: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0023: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0024: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0025: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0026: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0027: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0028: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0029: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0030: aLIGO CABLE PEG        (remove part)
D1300060-V1-00-0005: aLIGO OMC BRACKET, MASS MOUNTING        (remove part)
D1300060-V1-00-0006: aLIGO OMC BRACKET, MASS MOUNTING        (remove part)


====================================
More entries to be added (Found in the LHO OMC entry) [DONE]
D1300371-V2-00-S1301806: ISC DCPD Cable for OMC-Breadboard Bracket to DCPD #1
D1300372-V2-00-S1301807: ISC DCPD Cable for OMC-Breadboard Bracket to DCPD #2
D1300373-V3-00-S1301810: ISC QPD Cable for OMC-Structure to Breadboard Bracket
D1300374-V2-00-S1301813: ISC QPD Cable for OMC-Breadboard Bracket to QPD #1

Entry  Thu May 23 23:27:38 2019, Koji, Optics, Characterization, IGHQEX3000 high power test HQEPD_high_power_test.pdfpd_images.png

LaserComponents IGHQEX3000 (Cage B2: Serial# B1-23) was exposed to the beam with the optical power from 1.6mW to 332mW.
After each illumination, the dark current and the dark noise level were measured. Also the photo image of the PD surface was taken each time.

- No significant change of the dark current after each illumination.

- No significant change of the dark noise after each illumination.

- No visible change of the surface observed.

(During this dark noise measurement, the current amp gain was set to be 1e8 V/A, instead of 1e7 for the measurements yesterday.)

    Reply  Sun Nov 22 13:49:12 2020, Koji, Electronics, Characterization, Impedance Measurement for InGaAs QPDs impedance_measurement.pdfP_20201121_183830.jpgimpedance_test.pdfQ3000_impedance_test.pdf

To know any anomaly to the junction capacitance of the QPD segments, the RF impedances were tested with a hand-made impedance measurement.
All segments look almost identical in terms of capacitance.

Measurement setup:
The impedance of a device can be measured, for example, from the complex reflection coefficient (S11). To measure the reflection, a bidirectional coupler was brought from the 40m. Attachments 1 and 2 shows the connection. The quantity A/R shows S11. The network analyzer can convert a raw transfer function to an impedance in Ohm.

Calibration and Measurement limit:
The network analyzer was calibrated with 1) a piece of wire to short the clips 2) 50ohm resistor 3) open clips. Then the setup was tested with these three conditions (again). Attachment 3 shows the result. Because of the impedance variation of the system (mainly from the Pomona clip, I guess), there looks the systematic measurement error of ~1pF or ~25nH. Above 100MHz, the effect of the stray impedance is large such that the measurement is not reliable.

The setup was tested with a 10pF ceramic capacitor and this indicated it is accurate at this level. The setup is sufficient for measuring the diode junction capacitance of 300~500pF.

Impedance of the QPD segments:

Then the impedances of the QPD segments were measured (Attachment 4). The segments showed the identical capacitance of 300~400pF level, except for the variation of the stray inductance at high freq, which we can ignore. Note that there is no bias voltage applied and the nominal capacitance in the datasheet is 225pF at 5V reverse bias. So I can conclude that the QPDs are quite nominal in terms of the junction capacitance.

(Ed: 11/23/2020 The RF components were returned to the 40m)

Entry  Mon Jul 2 12:29:01 2018, Koji, Electronics, Characterization, Impedances of individual components (3IFO EOM) impedance_coils.pdfimpedance_xtals.pdfq_coils.pdfcomponent_models.pdfliso_models.zip

[Rich Koji]

The impedances of the individual components from the 3IFO EOM (before modification) were tested.
Each component was modeled by LISO. The LISO model (in PDF and txt) are attached at the end of the entry.

Coils
There are three inductors taken from the EOM unit. They showed the Q ranging from 150~300.
Their impedances are compared with the coil taken from the 9MHz port of the spare EOM (=current LHO EOM).
The inductance of the 8.7MHz inductor indicated higher L but still higher Q.

Todd made a replica of the 45.3MHz coil. He used a silver plated wire and it actually showed highest Q of ~400.

Crystal capacitance
The crystal capacitances were measured by attaching a test rig on the DB15 connector of the crystal housing. The rig was calibrated such that the impedances of the attched components on the rig were measured. They showed somewhat similar feature with parasitic resonances at ~50MHz. Above this frequnecy the capacitance went down (i.e. Abs(Z) went up). This indicates there are stray series LCR in pararrel to the crystal. Not sure what is the cause of this.

The central (24.1MHz) port showed smaller capacitance. This probably means the plates for the central port is smaller. Not sure the actual dimensions of the plates for this unit.
 

Entry  Thu Oct 18 20:23:33 2012, Koji, Optics, Characterization, Improved measurement Cav_scan_response_zoom_20121017.pdfdetailed_RoC_setup.pdf

Significant improvement has been achieved in the RoC measurement.

  • The trans PD has much more power as the BS at the cavity trans was replaced by a 50% BS. This covers the disadvantage of using the a Si PD.
  • The BB EOM has a 50Ohm terminator to ensure the 50Ohm termination at Low freq.
  • The length of the cavity was changed from 1.2m to 1.8m in order to see the effect on the RoC measurement.

By these changes, dramatic increase of the signal to noise ratio was seen.

Now both of the peaks corresponds to the 1st-order higher-order modes are clearly seen.
The peak at around 26MHz are produced by the beat between the carrier TEM00 and the upper-sideband TEM01 (or 10).
The other peak at around 57MHz are produced by the lower-sideband TEM01 (or 10).

 

Peak fitting

From the peak fitting we can extract the following numbers:

  • Cavity FSR (hence the cavity length)
  • Cavity g-factor
  • Approximate measure of the cavity bandwidth

Note that the cavity itself has not been touched during the measurement.
Only the laser frequency and the incident beam alignment were adjusted.

The results are calculated by the combination of MATLAB and Mathemaica. The fit results are listed in the PDF files.
In deed the fitting quality was not satisfactory if the single Lorentzian peak was assumed.

There for two peaks closely lining up with different height. This explained slight asymmetry of the side tails

This suggests that there is slight astigmatism on the mirrors (why not.)

The key points of the results:

- FSR and the cavity length: 83.28~83.31MHz / L=1.799~1.800 [m] (surprisingly good orecision of my optics placement!)

- Cavity g-factor: Considering the flatness of the flat mirror from the phase map, the measured g-factors were converted to the curvature of the curved mirror.
RoC = 2.583~4 [m] and 2.564~7 [m]. (Note: This fluctuation can not be explained by the statistical error.)
The mode split is an order of 10kHz. This number also agrees with the measurement taken yesterday.

If the curved mirror had the nominal curvature of 2.5m, the flat mirror should have the curvature of ~20m. This is very unlikely.

- Approximate cavity line width: FWHM = 70~80kHz. This corresponds to the finesse of ~500. The design value is ~780.
This means that the locking offset is not enough to explain the RoC discrepancy between the design and the measurement.

 

Entry  Thu May 9 16:07:18 2019, Stephen, Mechanics, General, Improvements to OMC Bonding Fixture image_of_issue_with_OMC_PZT_bonding_fixture_from_D16003336-v3.pngimage_02_of_issue_with_OMC_PZT_bonding_fixture_from_D16003336-v3.PNG

[Stephen, Koji]

As mentioned in eLOG 331, either increased thermal cycling or apparent improvements in cured EP30-2 strength led to fracture of curved mirrors at unintended locations of bonding to the PEEK fixture parts.

The issue and intended resolution is summarized in the attached images (2 different visualizations of the same item).

Redline has been posted to D1600336-v3.

Drawing update will be processed shortly, and parts will be modified to D1600336-v4.

 

Entry  Tue Aug 23 23:36:54 2016, Koji, Optics, Characterization, Inspection of the damaged CM1 (prev H1OMC) 7x

1. Calum and GariLynn checking the CM1 defect from the front side.
2. Same as above
3. Close up of the defect
4. Using dino-lite microscope to get a close up view of the defect from the front surface.
5. Same as 4
6. Finished for the day and setting up a safefy clamp
7. Finally a tefron cover was attached.

    Reply  Thu Aug 25 02:17:09 2016, Koji, Optics, Characterization, Inspection of the damaged CM1 (prev H1OMC) 

Initial inspection results by Calum, et al.
https://dcc.ligo.org/LIGO-E1600268

Entry  Fri Nov 20 18:51:23 2020, Koji, General, General, Instrument loan 

FEMTO DLPCA200 low noise preamp (brand new)

Keithley Source Meter 2450 (brand new) => Returned 11/23/2020

were brought to the OMC lab for temporary use.

https://nodus.ligo.caltech.edu:8081/QIL/2522

Entry  Mon May 13 14:59:16 2013, Koji, Mechanics, General, Invar shim gluing 

The invar reinforcement shims were glued on the glass brackets on the breadboard.
We worked on the light side on May 10th and did on the dark side on May 13rd.

U-shaped holding pieces are used to prevent each invar shim to be slipped from the right place.

We are going to bring the OMC breadboard to the bake oven tomorrow to cure the epoxies and promote the outgasing.

Entry  Thu Jul 31 15:07:53 2014, Koji, General, General, Item lending 

Tara: Laser Safety goggle -> Returned

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

    Reply  Fri Jan 30 19:31:08 2015, Koji, General, General, Item lending 

Gabriele:

PZT HV Amp

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)Returned March 23, 2016
Black glass beam dump

Dmass:

LB1005 Oct 24. This unit is permanently gone to Cryo lab. Acquired a new unit. Aug, 2016.

Quote:

Tara: Laser Safety goggle -> Returned

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

 

    Reply  Tue Feb 3 18:23:49 2015, Koji, General, General, Item lending 

- The laser was removed and shipped to LHO today.

- UV illuminator / fused silica fiber light guide / UV power meter / UV face shield (Qty 2) will be shipped to MIT.
They are CIT properties except for the illuminator.

Quote:

Gabriele:

PZT HV Amp

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

Quote:

Tara: Laser Safety goggle -> Returned

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

 

 

    Reply  Wed Feb 4 20:07:24 2015, Koji, General, General, Item lending C30140_1.JPGC30140_2.JPGC30141.JPGC30142.JPGC30143.JPG

Shipment to MIT (L. Barsotti, J. Miller)

1. UV Illuminator (LESCO Super Spot MK III)

2. UV Power meter (American Ultraviolet AIB1001) Caltech property C30140

3. UV protection face shield (VWR UVC-803) Qty.2 Caltech property C30141/C30142

4. UV Fiber Optic Light Guide (American Ultraviolet OLB1081) C30143

All returned: Aug 30, 2016

    Reply  Tue Jul 21 20:20:12 2015, Koji, General, General, Item lending 

Kate (ATF)

- 4ch color oscilloscope (Tektronix)

- Chopper controller

- Chopper with a rotating disk

    Reply  Fri Sep 9 14:34:31 2016, Koji, General, General, Item lending 

To 40m

First Contact Kit by Calum

Class A Kapton sheets

 

    Reply  Thu Feb 27 14:31:13 2020, Koji, General, General, Item lending P_20200227_134755_vHDR_On.jpg

Item lending as per Ian's request: Particle Counter from OMC Lab to QIL

 

ELOG V3.1.3-