ID |
Date |
Author |
Type |
Category |
Subject |
160
|
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 |
161
|
Fri Aug 30 12:14:50 2013 |
Koji | Optics | General | H1 OMC Cavity length adjustment |
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.

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.

|
Attachment 1: Gouy_FSR_130827.nb.zip
|
162
|
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. |
164
|
Fri Aug 30 12:25:29 2013 |
Koji | General | General | H1 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 |
Attachment 1: P8304368.JPG
|
|
Attachment 2: P8304370.JPG
|
|
165
|
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 |
166
|
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. |
167
|
Sat Sep 7 17:20:56 2013 |
Koji | General | General | OMC/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. |
Attachment 1: P9064377.JPG
|
|
168
|
Fri Sep 13 15:09:20 2013 |
Koji | General | General | Sprinkler installation: done |
A sprinkler head was installed on the HEPA enclosure. The head is covered with a plastic cap. |
Attachment 1: P9134379.jpg
|
|
Attachment 2: P9134378.jpg
|
|
173
|
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. |
174
|
Wed Oct 23 02:45:07 2013 |
Koji | General | General | PD 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 |
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
|
176
|
Thu Nov 21 00:05:35 2013 |
Koji | General | General | H1OMC 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
|
Attachment 1: H1OMC_cable_arrangement.pdf
|
|
177
|
Tue Dec 10 16:41:51 2013 |
Koji | General | General | To Buy |
Masks / Wipes => done |
178
|
Tue Feb 18 18:58:38 2014 |
Koji | General | General | LHO H1 OMC installation photos |
LHO OMC installation photos
|
179
|
Fri Feb 28 19:50:11 2014 |
Koji | General | General | Misalignment 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 |
Attachment 1: misalignment.pdf
|
|
182
|
Thu Apr 17 21:39:25 2014 |
Koji | Optics | General | More alignment |
STORY:
- The cavity mirrors have scattering spots. The cavity alignment should have been scanned to find a cavity mode to have lowest loss possible.
BTW, We only have horizontal dof for the alignment scan.
- After some struggle nice cavity mode was found. The cavity transmission was 96% for the ideally matched TEM00 carrier.
- It turned out that this imposed too much beam shift in the input beam (~2mm).
- This big shift induces a lot of trouble for the peripheral optics (PDs, QPDs, sterring mirrors).
- What should we do???
Analysis:
- The beam needed to go up between CM1 and CM2 to have the right spots on them. ("UP" is the input side of the OMC).
- This imposed the beam between FM1 and FM2 moved up. In other word, for the given alignment of the FMs by the template,
We needed to hit the upper part of the FMs to have the spots on the CMs up.
Solution:
- The above argument suggets that the nominal beam will give us the right spots on the CMs if we rotate the FMs.
Of course this induces the spot move on the FMs. But this should not be the issue as the most of the loss seems to come from the CMs.
- How much misalignment show we give to the FMs? We want to shift the beam by 2mm on the CMs.
The length of the optical lever is ~0.25m. Therefore the mialignment angle should be
theta = 2e-3/2/0.25 = 4e-3 rad = 4mrad.
The template pad has ~20mm separation. The thickness of the shim should be 20mm*4mrad = 80um
- Our aluminum foil seems to have the thickness of 30-40um. We can't have this minimum thickness on the template pad as there is not enough compression pressure
=> Just use a single layer of Al piece to shim the FMs.
Attempt:
- The shims were inserted at the upper pads of the FMs.
- Aligned the input beam and the CMs so that the spots on the CMs are approximately recovered.
- Measure the cavity power budget
Pin: 34.7mW
Refl PD: offset = -7.5mV, unlock = 6.07V, inlock = 89.7mV
Ptrans = 32.5mW
Ptrans(CM2) = 0.181mW
Ptrans(CM2) = 0.184mW
Assume finesse of 400
==>
Pin: 34.7mW
Pjunk: 0.534mW
Pcoupled: 34.1mW
Mode matching: 98.5%
Cavity reflectivity in power: 0.00061
Cavity transmission in power: 0.951 (This is not a best number but acceptable.)
Loss per mirror: 75.4ppm
FM power refl/trans: 0.9923 / 7630ppm
CM1 power refl/trans: 0.999882 / 42.8ppm
CM2 power refl/trans: 0.999881 / 43.5ppm
Total roundtrip loss of the cavity (Loss + CM leakage): 388ppm
Result:
How much the input beam is away from the left wall of the OMC breadboard?
40.88mm from the template edge
8.36mm between the template edge and the bread board
=> 32.52mm
How much should this number be? 32.94mm from the solidworks model => With in 0.5mm! Nice!
Next:
- Just in case plce all of the optics and check if the beam is delivered within the alignment range of the optics
|
187
|
Thu Jun 19 23:16:50 2014 |
Koji | Optics | General | All of the prisms have been glued |
- All of the PRISM mirrors have been glued
- 4 out of 5 beam dumps have been glued
TODO
EP30-2 gluing of the INVAR blocks for the PDs
PDs/QPDs need to be slightly lower -> order more shims
Remove the templates
Glue the last beam dump
Vibration test?
Bring the OMC to the bake lab
Vacuum baking
Bring it back to the OMC lab
Cabling / Wiring
Optical tests
Backscattering test
Packing / Shipping

|
188
|
Fri Jun 20 18:59:12 2014 |
Koji | Optics | General | All of the invar blocks have been glued |
All of the INVAR blocks have been glued.
I found thinner shims in the stock.
On Monday, the template will be removed.
EP30-2 7g mixed with 0.35g of 75-90um sphere
TODO
EP30-2 gluing of the INVAR blocks for the PDs
PDs/QPDs need to be slightly lower -> order more shims
Remove the templates
Glue the last beam dump
Vibration test?
Bring the OMC to the bake lab
Vacuum baking
Bring it back to the OMC lab
Cabling / Wiring
Optical tests
Backscattering test
Packing / Shipping |
189
|
Mon Jun 23 21:54:16 2014 |
Koji | Optics | General | All of the gluing completed |
The bottom-side templates were removed.
The last beam dump was removed
TODO
ICS entry
Bring the OMC to the bake lab
Vacuum baking
Bring it back to the OMC lab
Cabling / Wiring
VIbratin test
Optical tests
Backscattering test
Packing / Shipping
|
190
|
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 |
191
|
Fri Jun 27 12:29:50 2014 |
Koji | General | General | OMC 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

|
192
|
Fri Jun 27 18:51:33 2014 |
Koji | General | General | Supply |
PTOUCH TAPE (12mm white) x 2
9V batteries |
193
|
Wed Jul 2 16:41:43 2014 |
Koji | General | General | OMC 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 |
Koji | General | General | Beam 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.
|
Attachment 1: beamdump_delamination.png
|
|
195
|
Thu Jul 3 17:45:18 2014 |
Koji | General | General | Beam 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.

|
196
|
Sun Jul 6 02:45:56 2014 |
Koji | Optics | General | FSR Measurement |
3rd OMC FSR / Finesse measurement
RF AM was injected by detuning a HWP. |
Attachment 1: finesse_measurements_log.pdf
|
|
200
|
Mon Jul 7 01:36:03 2014 |
Koji | General | General | 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
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 |
Koji | General | General | Expoxy 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.
|
203
|
Thu Jul 10 01:39:38 2014 |
Koji | Electronics | General | PZT wire |
Rich came to the OMC lab. Pins for the mighty mouse connector were crimped on the 4 PZT wires.
We found the male 4pin mighty mouse connector in the C&B area.
The cable inventory was checked with ICS/DCC combo. It turned out that most of the on-board cables
are at LHO. We decided to send the OMC there and then the cables are installed at the site. |
Attachment 1: P7096669.JPG
|
|
204
|
Thu Jul 10 08:34:57 2014 |
Koji | General | General | 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
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 |
Koji | General | General | The 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 |
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.
|
215
|
Mon Aug 4 18:59:50 2014 |
Koji | General | General | A memorandom |
On breadboarfd cabling for 3IFO OMC
D1300371 - S1301806
D1300372 - S1301808
D1300374 - S1301813
D1300375 - S1301815 |
216
|
Tue Aug 5 13:03:25 2014 |
Koji | General | General | Missing 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 |
Koji | General | General | 3rd 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 |
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.
|
|
221
|
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.
|
|
|
222
|
Wed Feb 4 20:07:24 2015 |
Koji | General | General | Item 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 |
Attachment 1: C30140_1.JPG
|
|
Attachment 2: C30140_2.JPG
|
|
Attachment 3: C30141.JPG
|
|
Attachment 4: C30142.JPG
|
|
Attachment 5: C30143.JPG
|
|
223
|
Wed Feb 18 21:51:23 2015 |
Koji | General | General | Notes 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 |
Koji | General | General | Item lending |
Kate (ATF)
- 4ch color oscilloscope (Tektronix)
- Chopper controller
- Chopper with a rotating disk
|
235
|
Thu Aug 20 01:35:01 2015 |
Koji | Electronics | General | OMC DCPD in-vacuum electronics chain test |
We wanted to know the transimpedance of the OMC DCPD at high frequency (1M~10M).
For this purpose, the OMC DCPD chain was built at the 40m. The measurement setup is shown in Attachment 1.
- As the preamp box has the differential output (pin1 and pin6 of the last DB9), pomona clips were used to measure the transfer functions for the pos and neg outputs individually.
- In order to calibrate the measurements into transimpedances, New Focus 1611 is used. The output of this PD is AC coupled below 30kHz.
This cutoff was calibrated using another broadband PD (Thorlabs PDA255 ~50MHz).
Result: Attachment 2
- Up to 1MHz, the transimpedance matched well with the expected AF transfer function. At 1MHz the transimpedance is 400.
- Above 1MHz, sharp cut off at 3MHz was found. This is consistent with the openloop TF of LT1128.
|
Attachment 1: OMC_DCPD_Chain.pdf
|
|
Attachment 2: OMC_DCPD_Transimpedance.pdf
|
|
236
|
Wed Aug 26 11:31:33 2015 |
Koji | Electronics | General | OMC DCPD in-vacuum electronics chain test |
The noise levels of the output pins (pin1/pin6) are measured. Note that the measurement is done with SE. i.e. There was no common mode noise rejection. |
Attachment 1: OMC_DCPD_OutputNoise.pdf
|
|
239
|
Sun Sep 6 16:50:51 2015 |
Koji | Electronics | General | Unit test of the EOM/AOM Driver S1500118 |
TEST Result: S1500118
Additional notes
- Checked the power supply. All voltages look quiet and stationary.
- Checked the internal RF cables too see if there is any missing shield soldering => Looked fine
- Noticed that the RFAM detector board has +/-21V for the +/-24V lines => It seems that this is nominal according to the schematic
- Noticed that the RFAM detector sensitivity were doubled fomr the other unit.
=> This is reated to the modification (E1500353) of "Controller Board D0900761-B Change 1" (doubling the monitor output gain)
- Noticed that the transfer function of the CTRL signal on the BNC and the DAQ output.
=> This is reated to the modification (E1500353) of "Servo Board D0900847-B Change 1" (servo transfer function chage)
=> The measured transfer function did not agree with the prediction from the circuit constants in this document
=> From the observation of the servo board it was found that R69 was not 200Ohm but 66.5 Ohm (See attachment 1).
This explained the measured transfer function. The actuator TF has: P 2.36, Z 120., K -1@DC (0.020@HF)
- Similarly, the TF between the CTRL port on the unit and the CTRL port on the test rig was also modified.
Noise level
Attachment 2
- The amplitude noise in dBc (SSB) was measured at the output of 27dBm. From the test sheet, the noise level with 13dBm output was also referred. From the coherence of the MON1 and MON2, the noise level was inferred. It suggests that the floor level is better than 180dBc/Hz. However, there is a 1/f like noise below 1k and is dominating the actual noise level of the RF output. Daniel suggested that we should check nonlinear downconversion from the high frequency noise due to the noise attenuator. This will be check with the coming units. |
Attachment 1: P9037810.JPG
|
|
Attachment 2: RF_AM_spectra.pdf
|
|
249
|
Tue Dec 29 12:15:46 2015 |
Koji | General | General | Glasgow polarizer passed to Kate |
The Glasgow polarizer was passed to Kate on Dec 17, 2015. |
262
|
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) |
264
|
Mon Aug 15 10:09:10 2016 |
Koji | General | General | Prev 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 |
Koji | General | General | UV 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 |
Koji | General | General | Item lending |
To 40m
First Contact Kit by Calum
Class A Kapton sheets
|
269
|
Fri Sep 9 19:43:32 2016 |
Koji | Optics | General | D1102211 OMC Diode Mount Glass Block went to Downs |
D1102211 OMC Diode Mount Glass Block (11pcs) have been given to Calum@Downs |
270
|
Mon Nov 21 21:19:20 2016 |
Koji | Optics | General | LWE NPRO Laser / Input Optics / Fiber Coupling |
- About 1.5 month ago, an 700mW LWE NPRO has been brought to OMC Lab.
- The SOP can be found here.
- The base was made for the beam elevation of 3" height. Four 1" pedestals were attached to rise the beam elevation to 4".
- The output from the laser is ~740mW
- After the faraday and the BB EOM, the output is ~660mW
- After the usual struggle, the beam was coupled to the SM fiber. The output is 540mW. The coupling efficiency is >80%.
- Will proceed to the OMC cavity alignment. |