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Birefringence mitigation (LC)
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ShalikaSingh - 08:39, Thursday 30 May 2024 (3581)Get code to link to this report
Comment to Stability Check of Setup (Click here to view original report: 3580)

After an hour(ish) there was 460 points. 

So, I have increased the wait time to 30s and had started measurment for long term yesterday

filename: C:\Users\atama\OneDrive\LC-Experiment\Measurement Data\Stability Check\Wed, May 29, 2024 11-25-51 PM.txt

 

Also, for some time I have noticed an isssue with Labview on Bigfoot PC. It closes automatically on its own. I don't know if something is crashing but this is happening even when there is no windows update. But, has been happening more since last windows update. Unsure if its due to some bug. 

Birefringence mitigation (LC)
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ShalikaSingh - 21:54, Wednesday 29 May 2024 (3580)Get code to link to this report
Stability Check of Setup

We are now just saving some data at 10 seconds interval for about an hour, to see 

1. size of file generated (to understand what should be the wait time inlabview to have reasonable file size with same measurement continued for 1 day)

2. see how much deviation can the setup have if nothing is changing.

The camera is in transmission after BS.

foldername=C:\Users\atama\OneDrive\LC-Experiment\Measurement Data\Stability Check

The wait time is 10s and averaging is off

filename = Wed, May 29, 2024 9-47-22 PM.txt

Comments related to this report
ShalikaSingh - 08:39, Thursday 30 May 2024 (3581)

After an hour(ish) there was 460 points. 

So, I have increased the wait time to 30s and had started measurment for long term yesterday

filename: C:\Users\atama\OneDrive\LC-Experiment\Measurement Data\Stability Check\Wed, May 29, 2024 11-25-51 PM.txt

 

Also, for some time I have noticed an isssue with Labview on Bigfoot PC. It closes automatically on its own. I don't know if something is crashing but this is happening even when there is no windows update. But, has been happening more since last windows update. Unsure if its due to some bug. 

ShalikaSingh - 08:21, Friday 31 May 2024 (3582)

Tried to resolve labview crash/disappearing issue by

1. Tools>> Advanced>>Clear Compiled Object Cache

2. Windows Update

3. Added exclusion in windows defender for .vi programs

KAGRA MIR (General)
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ShalikaSingh - 18:02, Wednesday 29 May 2024 (3579)Get code to link to this report
Comment to Labview modification for camera integration (Click here to view original report: 3575)

In "MovereadWritewithCam" file, I replaced the items where lockin amp signal were sent to write into measurement file with the ones from camera

KAGRA MIR (General)
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ShalikaSingh - 17:59, Wednesday 29 May 2024 (3578)Get code to link to this report
Comment to Labview modification for camera integration (Click here to view original report: 3575)

Further Modification that were done

1. Duplicated average filter that was used and made modification to accomodate Azi, Ell, Power, S1, S2, S3 from camera. 

2. Duplicated "Move, wait, read, write" VI to make new and introduced pol cam control subvi inside it. Can save signal from camera now here, instead of lockin amp

3. Create a new global variable file for variable from camera

R&D (Cryogenic)
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ORishabhBajpai - 17:40, Wednesday 29 May 2024 (3577)Get code to link to this report
Testing Parallel Cryocooler Operation

With Matsuo-san

Overview: Today, we tested if the cryocooler in our Lab can be operated in parallel with Matsuo-san cryocooler.

Conclusion: We cannot operate them together.

Deatils: One of the cryocolers in Matsuo-san's lab was already operating. At first, we closed the valve connected to the input of the GWSP cryocooler and observed the water pressure in Matsuo-sans lab.

The pressure with the valve open was: 0.25 MPa

After closing the valve, the pressure was: 0.28 MPa

Based on this we concluded that water was flowing into the GWSP cryocooler. After confirming this, we opened the valve again and turned on the cryocooler. At this point, I realized I had made some errors in the temperature sensor cabling as the readings were all over. Since the goal was to confirm the parallel operation, I continued with cooling. The cryocooler was turned on at 11:28 and was atleast working until 11:50 when I left the lab. When I returned around 12:50, the cryocooler was off and showed "Motor Temp: Err", so I concluded that the water pressure was insufficient for parallel operation and the compressor overheated. However, the compressor was not too hot to touch but may have just turned off a while ago. One thing to note is that the manual suggests using the arrow key and confirming that the LED display also shows "Water Flow Err" to confirm the issue is low water pressure, but I forgot to do this. In any case, the conclusion is that two cryocoolers can't be operated in parallel.

Side Note: As previously reported, there are two sensors somewhere inside the cryostat, but I could not see them (I asked about it to Satoshi Tanioka at GWADW but he doesn't remember). However, since the temperature of this sensor did not drop drastically, I concluded they are not connected to the cold-head. I will look for them again when I open the cryostat.

Next Step: I am now discussing with Matsuo-san to have standalone test for our cryocooler to confrim if the water pressure is enough. Also, we should try to install a pressure guage near the water supply for our cryocooler.

KAGRA MIR (General)
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ShalikaSingh - 13:16, Wednesday 29 May 2024 (3576)Get code to link to this report
Comment to Labview modification for camera integration (Click here to view original report: 3575)

The error was due to mismatch between 64bit windows and 32 bit labview version. The problem has been resolved and the version of thorlabs labview module was synced to identify libraries for 32 bit 

KAGRA MIR (General)
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ShalikaSingh - 08:37, Wednesday 29 May 2024 (3575)Get code to link to this report
Labview modification for camera integration

1. ON PCI PC: We needed Thorlabs camera in PCI. There was conflict between the version of labview that was used to make VIs for Bigfoot pc and the PCI pc. Sadly, we can't open labview made in new version in a labview of olderversion. Which meant had to make it again for pci pc. 

2. In any case, the three subvi are prepared for start, control and closing the camera. Just need to resolve the issue of identifying camera by labview. Currently labview can't detect the software and libraries of camera. We had similar issue in past which happened due to poor installation methods (like plugging in camera before installation, or not restarting the pc)

Comments related to this report
ShalikaSingh - 13:16, Wednesday 29 May 2024 (3576)

The error was due to mismatch between 64bit windows and 32 bit labview version. The problem has been resolved and the version of thorlabs labview module was synced to identify libraries for 32 bit 

ShalikaSingh - 17:59, Wednesday 29 May 2024 (3578)

Further Modification that were done

1. Duplicated average filter that was used and made modification to accomodate Azi, Ell, Power, S1, S2, S3 from camera. 

2. Duplicated "Move, wait, read, write" VI to make new and introduced pol cam control subvi inside it. Can save signal from camera now here, instead of lockin amp

3. Create a new global variable file for variable from camera

ShalikaSingh - 18:02, Wednesday 29 May 2024 (3579)

In "MovereadWritewithCam" file, I replaced the items where lockin amp signal were sent to write into measurement file with the ones from camera

ShalikaSingh - 08:23, Friday 31 May 2024 (3583)

In the averaging filter VI made copy of the previous filter 6 times to be able to filter Azimuth, Ellipticity, Power, S1, S2, S3. All of their output were added in cluster for ease of transfeering data from one Vi to another. In the Buffer filter file also I made the buffer for all variables.

The output of averaging filter was connected to the graphical displays on the main VI. The VI is perhaps ready for initial tests and for checking if everything was replaced in a proper manner. 

ShalikaSingh - 08:37, Friday 31 May 2024 (3584)

Also, In "Move read write with Cam" Vi there is a place where the lockin data was used to make the matrix for the map which is visible in the main VI. Since the previous configuration only allowed one input here, I only added ellipticity from the camera. Not sure how to introduce azimuth here on one single map.

ShalikaSingh - 06:44, Monday 17 June 2024 (3614)

The format of saving is of the form:

X, Y, Ellipticity, Azimuth, Power, s1, s2, s3

Birefringence mitigation (General)
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ShalikaSingh - 08:37, Wednesday 29 May 2024 (3574)Get code to link to this report
Labview modifications

1. On Bigfoot PC: Increase buffer size for enhanced averaging. Can do upto 200 averages.

2. Also, decrease time  in iterating while loop to do long term stability checks.

R&D (FilterCavity)
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MichaelPage - 19:19, Tuesday 28 May 2024 (3572)Get code to link to this report
OPO recovery - initial Faraday insolator

Logan, Michael

Logan learned about how to adjust the transmission and blocking polarizer setup of the Faraday isolator. It seems everything was mostly in place regarding polarization - the required input is p-pol for IO-5-1064-HP. With current QWP/HWP setup about 300 to 1 p-pol vs s-pol could be reached, checked via PBS and power meter.

We thought there were some issues with the FI not transmitting close to 100% but this turned out to be putting the power meter too far upstream, and then also small alignment tweaks. I could get about 95%+ transmission just aligning by hand. I tried to tweak with the micro adjusters but it turns out the platform is stuck and adjusting yaw makes it bump upwards (hard to describe without a picture). We should buy a better mount.

The initial point of this exercise was to check the contribution of the FI to some weird possible HOM seen on the beam profiler, hence why I put the micro-adjuster underneath to adjust pitch and yaw of the FI. I think at this stage we should just get on with it - check the output of the FI with the beam profiler and see if we can get rid of the weird mode. Super optimal transmission is not so important.

General (General)
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MarcEisenmann - 19:10, Tuesday 28 May 2024 (3571)Get code to link to this report
internet issues

[Hugo, Marc, Shalika]

Since sometimes now (maybe from last electric shutdown) one of the wifi relay in the central building broke (in storage) room.

In addition the ethernet switch seems broken as well. NOC is aware of this issue.

In the mean time, we placed a small switch on top of LC table and connected all TAMA pcs to it. We get internet from the new DGS switch.

Internet is back on all pc but at least PCI pc has now issue finding the Matlab license...

KAGRA MIR (Polarization)
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MarcEisenmann - 19:08, Tuesday 28 May 2024 (3569)Get code to link to this report
birefringence measurement preparation

[Hugo, Marc, Shalika]

laser diode 1A : 1.6mW

z = 20 mm gives distance between blades and last mirror on injection = 171mm

 horizontal cut

Y: 103 mm cut (power halved) (power on dc 1.1) after hav power on dc was 0.55

X:374mm

z = 20 : Tue, May 28, 2024 2-14-49 PM.txt

z = 40 : Tue, May 28, 2024 2-21-29 PM.txt

z = 60: Tue, May 28, 2024 2-25-28 PM.txt

z = 80: Tue, May 28, 2024 2-29-48 PM.txt

 

verticale:

X: 313

Y : 191

z = 20 : Tue, May 28, 2024 11-32-57 AM.txt

z = 40 : Tue, May 28, 2024 2-01-31 PM.txt

z = 60: Tue, May 28, 2024 2-06-27 PM.txt

z = 80:Tue, May 28, 2024 2-10-41 PM.txt

after realignment horizontal

z = 20 : Tue, May 28, 2024 4-14-32 PM.txt

z = 40 : Tue, May 28, 2024 4-30-15 PM.txt

z = 60 : Tue, May 28, 2024 4-34-03 PM.txt

z = 80 : Tue, May 28, 2024 4-37-59 PM.txt

In the end we recovered normal incidence in both vertical and horizontal directions (within 0.026deg).

We wanted to prepare for linear polariscope measurement but the lockin amplifier showed strange error (undr) related to the chopper signal...

We'll start with polarization camera measurements in the coming days

R&D (FilterCavity)
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MarcEisenmann - 19:02, Tuesday 28 May 2024 (3570)Get code to link to this report
Comment to DDS2 issues investigation (Click here to view original report: 3560)

[Logan, Marc]

We added one of the 2 remaining RF amplifier to the 500MHz clock output.

We soldered it to the NIM rack +12V and ground used for the LNVR. Note that we could have tried to use the +12V from the LNVR but were a bit worried to further damaged the clock..

The output of the clock is now +7.9dBm.

The output of the following splitter are

1 : -1.73dBm ; 2 : -6.19 dBm ; 3 : -5.09 dBm ; 4 : -5.33 dBm

Finally, we connected DDS2 to each output of the splitter and checked the signal output from DAC0.

We got about -9 dBm from all.

Next steps are fixing the clock crystal (was not fixed anymore) and the RF amplifier ; recover the electronic connections and recover squeezing.

Birefringence mitigation (General)
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ShalikaSingh - 09:19, Monday 27 May 2024 (3567)Get code to link to this report
Comment to Optimization of Jones Matrix (Click here to view original report: 3564)

The birefringence properties remained same. Comes from the fact that we do J/Co

Birefringence mitigation (General)
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ShalikaSingh - 17:27, Sunday 26 May 2024 (3566)Get code to link to this report
Comment to optimization of jones matrix (Click here to view original report: 3562)

after adding this, the jones matrix and info on birefringence was weird....I lost the crcuial info on the polarization properties rather than it working as a proper filter. So, not using this anymore.

Had actually picked it from a paper talking about improving noise in jones matrix. 

Birefringence mitigation (General)
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ShalikaSingh - 17:23, Sunday 26 May 2024 (3565)Get code to link to this report
Comment to Optimization of Jones Matrix (Click here to view original report: 3564)

after this the jones matrix of mirror is not [1,0][0,-1] anymore. the 1's have changed to 0.8 ish. 

Birefringence mitigation (General)
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ShalikaSingh - 08:24, Sunday 26 May 2024 (3564)Get code to link to this report
Optimization of Jones Matrix

Added power factor of sqrt(Output power/ Input Power) in jones vector. This is to take account the power getting halved after BS

Comments related to this report
ShalikaSingh - 17:23, Sunday 26 May 2024 (3565)

after this the jones matrix of mirror is not [1,0][0,-1] anymore. the 1's have changed to 0.8 ish. 

ShalikaSingh - 09:19, Monday 27 May 2024 (3567)

The birefringence properties remained same. Comes from the fact that we do J/Co

Birefringence mitigation (cavity)
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HugoSaintOlive - 07:30, Saturday 25 May 2024 (3563)Get code to link to this report
Manipulation on the 2 AOM set up
I made the design of the set-up, I will use 4 different lenses to pass in the AOM probably, f=-50mm f=50mm f=-100mm f=200mm.


I removed the lens f=100mm and start to install the f=-50mm and f=50mm(not labeled yet) 10cm after the HWP.
Birefringence mitigation (General)
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ShalikaSingh - 13:51, Friday 24 May 2024 (3562)Get code to link to this report
optimization of jones matrix

put the condition on jones vector such that matrix is computed only for 2 orthogonal set of jones vector. 

so the dot product is supposed to be 0. I have kept the range to be 85-90 deg. Therefore the dot product is required to be less than 0.2

Comments related to this report
ShalikaSingh - 17:27, Sunday 26 May 2024 (3566)

after adding this, the jones matrix and info on birefringence was weird....I lost the crcuial info on the polarization properties rather than it working as a proper filter. So, not using this anymore.

Had actually picked it from a paper talking about improving noise in jones matrix. 

Birefringence mitigation (cavity)
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HugoSaintOlive - 10:16, Friday 24 May 2024 (3561)Get code to link to this report
New manipulation AOM
I use the begining of the set-up of the LCD and after the QWP and the HWP I put a lens f=100mm, and I characterize the beam.

Before the lens, w0 = -47,1 mm ; z0 = 26 μm , after the lens : w0 = 88.8 mm ; z0 = 49.2 μm

I moved the lens f=100mm after the characterization at d = 0.2 m (d = 0 is the same has the previous characterization)

!!!! The zero of reference did not correspond to any optic know, but it's at 101,5cm on the ruler, or the third a hole after the HWP.
R&D (FilterCavity)
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MarcEisenmann - 20:43, Thursday 23 May 2024 (3560)Get code to link to this report
DDS2 issues investigation

[Logan, Marc]

Following the reinstallation of the mixers box we could not lock the GRMC.

We found out  it was because the DDS2 was not generating any sidebands but was just outputing some low amplitude broadband noise.

We could see that this issue was somehow related to the 500MHz clock as the software could not recognize it from time to time.

Today we checked the DDS2.

All voltages supply are correct.

All output (filtered or not) are just noise increase.

Then we checked the 500 MHz clock output and got

Channel 1 : -8.6dBm

Channel 2 : -16.7dBm

Channel 3 : -19dBm

Channel 4 : -21 dBm

We checked the output of Wenzel output and got -8dBm.

It seems there are some issues with the splitter (ZFRSC-4-842-S+) that creates the low clock power.

We swapped the clock of DDS2 to channel 1 and got the expected output powers.

We'll check if the remaining amplifier can be used for this clock output or if we have to purchase a new splitter.

Comments related to this report
MarcEisenmann - 19:02, Tuesday 28 May 2024 (3570)

[Logan, Marc]

We added one of the 2 remaining RF amplifier to the 500MHz clock output.

We soldered it to the NIM rack +12V and ground used for the LNVR. Note that we could have tried to use the +12V from the LNVR but were a bit worried to further damaged the clock..

The output of the clock is now +7.9dBm.

The output of the following splitter are

1 : -1.73dBm ; 2 : -6.19 dBm ; 3 : -5.09 dBm ; 4 : -5.33 dBm

Finally, we connected DDS2 to each output of the splitter and checked the signal output from DAC0.

We got about -9 dBm from all.

Next steps are fixing the clock crystal (was not fixed anymore) and the RF amplifier ; recover the electronic connections and recover squeezing.