40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  OMC elog, Page 7 of 11  Not logged in ELOG logo
New entries since:Wed Dec 31 16:00:00 1969
ID Date Author Typedown Category Subject
  153   Fri Aug 16 17:21:38 2013 KojiGeneralGeneral[OMC002] Build started

[Jeff Koji]

The breadboard (SN2) was loaded on the transportation fixture.

The laser side template was installed and the cavity mirrors were placed.

The laser beam will be resonated in the cavity next week.

  164   Fri Aug 30 12:25:29 2013 KojiGeneralGeneralH1 OMC Invar mount gluing

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

  165   Tue Sep 3 17:03:25 2013 KojiGeneralGeneralH1 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

  166   Wed Sep 4 22:22:54 2013 KojiGeneralGeneralH1 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.

  167   Sat Sep 7 17:20:56 2013 KojiGeneralGeneralOMC/PD lab optical table wrapping

[Koji Jeff]

In order to prepare for the splinkler installation on the HEPA enclosure, the table with the optics was wrapped with Ameristat sheets.

  168   Fri Sep 13 15:09:20 2013 KojiGeneralGeneralSprinkler installation: done

A sprinkler head was installed on the HEPA enclosure. The head is covered with a plastic cap.

  173   Tue Oct 22 17:17:59 2013 KojiGeneralGeneralH1OMC 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.

  174   Wed Oct 23 02:45:07 2013 KojiGeneralGeneralPD realignment

DCPD2 got misaligned during the cable installation. The PD alignment procedure have been gone through again.

Cavity locking

- Removed the FC layers for the cavity related mirrors.

- Aligned and locked the cavity.

PD alignment

- Loosen DCPD2. Checked the reflection with a IR card. Checked the spot on the PD with an IR viewer.

- Finger-tight the screws. Check the reflection with the card again. Check the pot on the PD with a CCD.

- If the spot positions are not satisfactory repeat the process.

- If the spot positions are satisfactory, take pictures of the CCD image.

- Fixing screws for all of the PDs/QPDs were tighten by the torque driver with a torque od 1.75 inch lb.

PD QE measurements

- Measure the power incident on the PDs.

- Set up the transimpedance amp to check the photo current.

- PD1 (T side) 9.10+/-0.03 V 13.02 +/- 0.01W -> QE ~80%

- PD2 (R side) 8.70+/-0.01 V 12.53 +/- 0.01W -> QE ~80%

- These are not strange values considering the presence of the glass caps.

PZT polarity check

- The connections between the PZT electrodes and the pins were checked.

- The positive side is marked by a knot on the wire.

FC painting

- The new FC bottle was brought from Downs, thanks to Margot.

 

  175   Mon Nov 4 19:43:56 2013 KojiGeneralGeneralH1OMC 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
  176   Thu Nov 21 00:05:35 2013 KojiGeneralGeneralH1OMC electronics arrangement

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

  177   Tue Dec 10 16:41:51 2013 KojiGeneralGeneralTo Buy

Masks / Wipes => done

  178   Tue Feb 18 18:58:38 2014 KojiGeneralGeneralLHO H1 OMC installation photos

LHO OMC installation photos

  179   Fri Feb 28 19:50:11 2014 KojiGeneralGeneralMisalignment ABCD matrix for the aLIGO OMC

Relationship between mirror misalignment and cavity mode shift was calculated.
The technique described in T0900647 by Sam Waldman was used.

The angles and displacement of the mirrors and beams are defined in the attached figure.

x1 = 0.893134 α + 1.10676 β + 1.32252 γ + 1.24619 δ
𝛳1 = 0.75864 α - 0.75864 β - 0.271075 γ + 0.271075 δ

x2 = 1.10676 α + 0.893134 β + 1.24619 γ + 1.32252 δ
𝛳2 = 0.75864 α + 1.24136 β - 0.271075 γ + 0.271075 δ

x3 = 1.32252 α + 1.24619 β + 1.1691 γ + 1.39962 δ
𝛳3 = -0.271075 α + 0.271075 β + 0.818668 γ - 0.818668 δ

x4 = 1.24619 α + 1.32252 β + 1.39962 γ + 1.1691 δ
𝛳4 = -1.24136 α - 0.75864 β - 0.271075 γ + 0.271075 δ

Assuming the flat mirrors are fixed:
If I want to move the x3 mirror up by 1mm without moving x4, the solution is
γ = -0.00197 mrad
δ = +0.00236 mrad

This yields:
x1 = +0.33mm, x2=+0.66mm, x3 = +1mm, x4 = 0mm

  180   Mon Mar 3 02:46:21 2014 KojiGeneralCharacterizationSpot 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
Incident on BS1: 34.4mW

Reflection (Unlocked): 5.99V
Reflection (Locked): 104mV
Reflection (Dark): -7.5mV

to accomodate the spot on BS1 it had to be about a mm moved from the template.

This gives us:
- Portion of the TEM00 carrier: R = 1-(104+7.5)/(5990+7.5) = 0.981
- Raw transmission: 32.7/34.4 = 0.950
- TEM00 transmission 0.950/R = 0.969
- Excluding the transmission of BS1: 0.969/0.9926 = 0.976
  => loss per mirror ~40ppm

 

  190   Tue Jun 24 18:43:15 2014 KojiGeneralGeneralICS 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

  191   Fri Jun 27 12:29:50 2014 KojiGeneralGeneralOMC baking

The OMC went into the oven at around 2PM on Thursday. It will be baked at 80degC for 48 hours.
The RGA result will be obtained on Monday.

Link to the ICS entry

P6266536.jpg

  192   Fri Jun 27 18:51:33 2014 KojiGeneralGeneralSupply

PTOUCH TAPE (12mm white) x 2

9V batteries

  193   Wed Jul 2 16:41:43 2014 KojiGeneralGeneralOMC baking

OMC is back from the oven today.

To Do:

Optical tests

  • Cleaning
  • Power Budget
  • FSR measurement
  • TMS measurement
  • TMS measurement (with DC voltage on PZTs)
  • PZT DC response
  • PZT AC response
  • QPD alignment
  • DCPD alignment
  • First Contact

Backscattering test

Cabling / Wiring

  • Attaching cable/mass platforms
  • PZT cabling
  • DCPD cabling
  • QPD cabling

Vibration test

Packing / Shipping

  194   Wed Jul 2 18:58:42 2014 KojiGeneralGeneralBeam dump delamination

While the OMC breadboard was being inspected, it was found that two out of five black-glass beam dumps showed sign of delamination.
(attached photos).

The base of the each beam dump is a fused silica disk (25mm dia.). The black glass pieces are bonded to the disk. The bond is EP30-2
epoxy without glass beads for bond lining. The disk is bonded on the fused silica bread board with Optocast UV low-viscous epoxy.
The delamination is about 70% of the bonded area. They don't seem to fall off immediately. But the glass pieces are not completely secure.
(i.e. finger touch can change the newton ring fringes) So there might be some risk of falling off during transportation.

The engineering team and I are exploring the way to secure them in-situ, including the method to apply UV epoxy with capillary action.

  195   Thu Jul 3 17:45:18 2014 KojiGeneralGeneralBeam dump delamination

Here is the resolution.

I'll apply fillets of EP30-2 along the edges of the black glass (See figure).
In order to allow the air escape from the gap, the inside of the V will not be painted.
In any case, I don't have a good access to the interior of the V.

Dennis assured that the outgassing level will be ok even if the EP30-2 is cured at the room temp if the mixture is good.
But just in case, we should run an RGA scan (after 50degC for 24hour vac bake).
I prefer to do this RGA scan right after all of the test and cabling and right before the shipment.
Dennis is checking if we can even waive the RGA scan owing to the small volume of the glue.

beamdump_delamination_solution.png

  200   Mon Jul 7 01:36:03 2014 KojiGeneralGeneralTo Do

Optical tests

  • Cleaning
  • Power Budget
  • FSR measurement
  • TMS measurement
  • TMS measurement (with DC voltage on PZTs)
  • PZT DC response
  • PZT AC response
  • QPD alignment
  • DCPD alignment

Backscattering test

Cabling / Wiring

  • Attaching cable/mass platforms
  • PZT cabling
  • DCPD cabling
  • QPD cabling

Vibration test

Baking

First Contact

Packing / Shipping

  201   Tue Jul 8 04:08:06 2014 KojiGeneralGeneralExpoxy reapplication for beam dumps

Firstly, the excess epoxy was removed using a cleaned razor balde

Secondly, EP30-2 epoxy was applied at the exterior edges of the beam dump.
Interior of the V were glued at two points. This is to keep the gap away from being trapped

Here is the result of the gluing. Some epoxy was sucked into the gap by capillary action.
I believe, most of the rigidity is proivded by the bonds at the edges.

  204   Thu Jul 10 08:34:57 2014 KojiGeneralGeneralTo Do

Optical tests

  • Cleaning
  • Power Budget
  • FSR measurement
  • TMS measurement
  • TMS measurement (with DC voltage on PZTs)
  • PZT DC response
  • PZT AC response
  • QPD alignment
  • DCPD alignment

Backscattering test

Cabling / Wiring

  • Attaching cable/mass platforms
  • PZT cabling
  • DCPD cabling (to be done at LHO)
  • QPD cabling (to be done at LHO)

Vibration test

Baking

First Contact

Packing / Shipping

  212   Sun Jul 20 17:20:39 2014 KojiGeneralGeneralThe 3rd (LIO) OMC was shipped out to LHO

The 3rd (LIO) OMC was shipped out to LHO on Friday (Jul 18) Morning.

At LHO

- All of the on-breadboard cables should be attached and tied down.

- Peel First Contact paint and pack the OMC for storage.

 

  214   Thu Jul 31 15:07:53 2014 KojiGeneralGeneralItem lending

Tara: Laser Safety goggle -> Returned

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

Dmass:

LB1005 Oct 24.

  215   Mon Aug 4 18:59:50 2014 KojiGeneralGeneralA memorandom

On breadboarfd cabling for 3IFO OMC

D1300371 - S1301806
D1300372 - S1301808
D1300374 - S1301813
D1300375 - S1301815

  216   Tue Aug 5 13:03:25 2014 KojiGeneralGeneralMissing cable components

DCPD Connector Face: Qty2 https://dcc.ligo.org/LIGO-D1201276
QPD Connector Face: Qty2 https://dcc.ligo.org/LIGO-D1201282

PD faster: 92210A07 Qty 4: MCMASTER #2-56 x .25 FHCS

Spare DCPD

  219   Sat Jan 17 11:40:04 2015 KojiGeneralGeneral3rd OMC completed

Jan 15, 2015 3rd OMC completed

The face caps of the DCPD/QPD cables were installed (Helicoils inserted)
PD7&10 swapped with PD11(for DCPD T) and PD12(DCPD R).
Firct Contact coating removed

Note on the 3rd OMC

Before the 3rdOMC is actually used,

- First Contact should be applied again for preventing contamination during the installation

- DCPD glass windows should be removed

  220   Fri Jan 30 19:31:08 2015 KojiGeneralGeneralItem 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.

 

  221   Tue Feb 3 18:23:49 2015 KojiGeneralGeneralItem 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.

 

 

  222   Wed Feb 4 20:07:24 2015 KojiGeneralGeneralItem lending

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

  223   Wed Feb 18 21:51:23 2015 KojiGeneralGeneralNotes on OMC Transportation Fixtures & Pelican

LLO has one empty OMC transportation fixture.

LHO has one empty OMC transportation fixture.

LHO has one OMC transportation fixture with 3IFO OMC in it.

LHO has the Pelican trunk for the OMC transportation. Last time it was in the lab next to the optics lab.

  226   Tue Jul 21 20:20:12 2015 KojiGeneralGeneralItem lending

Kate (ATF)

- 4ch color oscilloscope (Tektronix)

- Chopper controller

- Chopper with a rotating disk

  248   Fri Dec 18 15:33:24 2015 KojiGeneralLoan / LendingLoan from Rich

Loan Record: I borrowed a PD can opener from Rich => Antonio Returned Sep 9, 2016

Tungsten Carbide Engraver (permanently given to the OMC lab)

KEITHLEY SOURCE METER + Laptop

  249   Tue Dec 29 12:15:46 2015 KojiGeneralGeneralGlasgow polarizer passed to Kate

The Glasgow polarizer was passed to Kate on Dec 17, 2015.

  250   Thu Feb 18 21:08:32 2016 KojiGeneralLoan / Lending(all returned) Antonio loan

Antonio borrowed: Rich's PD cutter (returned), Ohir power meter(returned), Thorlabs power meter head, Chopper

  258   Tue Apr 5 18:14:55 2016 KojiGeneralLoan / LendingQPD Lending Crackle

Xiaoyue

QPD head
X-Z stage
Mounting brackets
DB15 cable
QPD matrix circuit
+/-18V power supply cable

  261   Fri Jun 10 17:12:57 2016 KojiGeneralConfigurationL1 OMC DCPD replacement

New DCPD(T) = A1-23
DCPD(T) = DCPDB: extracted and accomodated in CAGE-G SLOT1

New DCPD(R) = A1-25
DCPD(R) = DCPDA: extracted and accomodated in CAGE-G SLOT2

  262   Fri Jul 22 22:24:05 2016 KojiGeneralGeneralHQEPD 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)

  263   Fri Aug 12 14:58:17 2016 KojiGeneralConfigurationH1 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

  264   Mon Aug 15 10:09:10 2016 KojiGeneralGeneralPrev H1 OMC shipped to CIT

Previous H1 OMC shipped from LHO to CIT

https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8196

  265   Mon Aug 22 12:58:16 2016 KojiGeneralGeneralUV bond samples -> Garilynn

- FS base + Mounting Prism

- FS or SF2 1/2" piece + FS or SF2 1/2" piece

- FS? plate + FS or SF2 1/2" piece + FS or SF2 1/2" piece + FS? plate

  268   Fri Sep 9 14:34:31 2016 KojiGeneralGeneralItem lending

To 40m

First Contact Kit by Calum

Class A Kapton sheets

 

  272   Wed Dec 7 21:18:35 2016 KojiGeneralGeneralOMC placed on the table / the beam roughly aligned

The OMC mode matching sled was fixed on the nominal part of the table. Then the OMC was located at the nominal position marked by three poles.

The input periscope was adjusted to have the input beam roughtly centered on the OMC QPDs. This made the beam from FM2 aligned to the missing CM1, and the beam just went through the hole of the mounting prism. Very promising!

I wanted to use the new (modified) mirror gluing fixture to hold a curved mirror on the mounting prism. It turned out that the fixture was neither cleaned nor assembled. I will ask Downs Team to help me to get the cleaned and assembled fixtures.

Meanwhile, I just reused the original gluing fixture upside down in order to proceed cavity alignment and locking. (Attachment 1)
In fact, once the mirror is placed on the mounting prism, the cavity started to flash without further alignment. I thank for the very precise (repeatable) alignment of the OMC optics and PD/QPDs.

The next steps are initial cavity locking, more alignment, and mode matching.

  273   Thu Dec 8 21:17:09 2016 KojiGeneralGeneralOMC placed on the table / the beam roughly aligned

The OMC cavity was locked. The alignment was precisely adjusted. The mode matching was optimized by the lens positions. The reflection during the lock is ~0.01 compared to the full reflection on non-resonance, meaning the mode matching is ~99%. The error signal was maximized (i.e. demod pahse was adjusted) by sweeping the modulation frequency. Note that the EOM is broad band. The modulation freq chosen today was 34.6MHz.

Some notes:

- The error signal has not been preamplified at all yet. Because of this, the reflection is very much sensitive to the input offset.

- The OMC needs wind shield to prevent from the noise caused by air turbulance.

- The laser PZT was actuated via the Thorlabs HV amp. Otherwise, the thermal path needs to be configured.

- One of the CCD monitor is dead. Needs more replacement.

- All the electronics should be moved to the rack. This required long BNC and SMA cables.

- The optical table needs cleaning.

  278   Fri May 26 21:53:20 2017 KojiGeneralConfigurationTrans RF PD setup

Recent work

- DC output of the trans RF PD was connected to the BNC patch panel. => Now CH4 of the scope is monitoring this signal

- The RF sweep signal from the network analyzer is connected to the power combiner for the EOM drive via the SMA patch panel.

- The trans RF PD was aligned first to the leakage beam. It turned out that this signal is too weak. Then the PD was aligned to one of the main OMC transmission. For this purpose, the OMC DCPD (T) was removed from the OMC breadboard.

- It seems that there is a significant amount of RF AM from the EOM. I suspect it is associated with the residual S-pol and birefringence of the steering mirrors (45deg HR). But the HWP at the output of the Faraday is fixed on the Faraday body with a screw and cumbersome for fine adjustment. A PBS and an HWP are added right before the EOM. This made the fiber coupler slightly misaligned. I suppose this new setup still has S&P on the fiber too. Thus, readjustment of the fiber rotations at the input is necessary.

Next step

- Input power to the fiber should be determined before the EOM. Otherwise, touching the HWP before the EOM causes too much power change at the optics of the OMC side.

- Precise adjustment of the RFAM is still necessary.

- The OMC curved mirror should be held by the new fixture.

- Check the beam spots

- Measure cavity parameters. (transmission/FSR/HOM/etc)

==> Then the curved mirror and the PZT will be glued on the prism

  279   Tue Jun 6 00:49:48 2017 KojiGeneralConfigurationTrans RF PD setup

Last week, I further worked on the RF system to install 20dB coupler on the agilent unit and setup the R channel. This allowed me to make the FSR/TMS measurement of the OMC.

And today several optical improvement has been done.

- The input/output fiber couplers were adjusted to have the maximum transmission through the PBS right before the OMC.
- The HWP on the output side of the faraday was adjusted to have ~40mW input to the OMC.

Then, the OMC curved mirror is now held by the new in-situ gluing fixture instead of the conventional fixture attached upside down.
The OMC was ocked again and the input alignment was adjutsed. The fixture is blocking the QPD path, so it's not possible to confirm the proper alignment of the cavity (w.r.t. the QPD paths).

The precise positions of the spots could not be confirmed as the battery of the IR viewer was empty. Quick check of the spots by the card tells that the spot on the CM2 (PD side) is slightly too close to FM2 (output coupler). I wonder if this could be solved by rotating the curved mirror.

Otherwise everything look good. Let's try to glue the curved mirror tomorrow.

Note: Spot on CM2 is too close to the edge of the hole on the mounting prism. The meausrementof CM1 is telling that the curverture center is located 2.7mm upper side of the center of the mirror if the HR side arrow is up (and it is the case). If we move the arrow to the QPD path side (90deg CW viewed from the face side), this corresponds to ~1.1mrad CCW tilt in Yaw (viewed from the top of the prism). According to the matrix calculation (T1500060) this will induce ~1.5mm shift of the beam. This should be tried before gluing.

  280   Tue Jun 6 22:00:36 2017 KojiGeneralConfigurationTrans RF PD setup

- Replaced the PZT with the one used from the beginning. This must be PZT #21. After the replacement, the spot positions look very good. I even went up. So I decided this is the configuration to proceed to the gluing. The CM1 mirror has the HR arrow at the top.

- The input beam was realigned w.r.t. the OMC.

- Tried to use the IR viewer with the new rechargable battery brought from the 40m. But the view still didn't work. The possibility is a) the viewer is broken b) the battery is empty.

- Tried to use the stainless clean regulartor for the UHP N2. The outlet has a short tube with a different diameter. The O.D. of the old tube is 6.3mm, while the new one is 9.5mm. If I insert the thinner tube in the new tube, it approximately fits. But I don't believe this is the way...

  284   Sat Jul 1 21:33:18 2017 KojiGeneralGeneralSome purchase notes

- Forgot to close the cylinder valve...

v HEPA prefilter (20"x20"x1" MERV 7)

- Replace the filter for the air conditioning

v Texwipe TX715 SWAB http://www.texwipe.com/store/p-817-tx715.aspx

v Gloves ~3 bags
VWR GLOVE ACCTCH NR-LTX SZ7.0 PK25 79999-304 x3
VWR GLOVE ACCTCH NR-LTX SZ7.5 PK25 79999-306 x1

v Vectra IPA soaked cloths

v Sticky mats


  • GLOVE ACCTCH NR-LTX SZ7 PK25 / 79999-304 / PK4
  • GLOVE ACCTCH NR-LTX SZ7.5 PK25 / 79999-306 / PK1
  • WIPER 100% IPA 23X23CM PK50. / TWTX8410 / PK2
  • SWAB CLEANTIPS ALPHA PK100. / TW-TX715 / PK1
  • MAT CLEAN ROOM 18X36IN BLUE / 89021-748 / CS1 (Qty4)
  • FILTER PLET AIR MERV8 20X20X1 / 78002-422 / EA4 / Direct from Supplier

ORDERED AUG 9, 2017

  285   Wed Jul 5 16:59:44 2017 KojiGeneralGeneralThe OMC #002 was packed

[Stephen Koji]

The OMC #002 was packed for the transportation to Downs.

===> And transported to Downs 227 on Jul 6th.

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