 Mon Sep 16 13:51:23 2024, Luis Martin, Update, VAC, RGA Scans 
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[Luis, Luke}
Three RGA scans were taken. The improvement in the amount of HC in the vacuum is visible across the different measurements.
Images are attached. |
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Mon Sep 16 07:28:16 2024, Luke, Update, Interferometer Simulations, Ring heater update
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Mon Sep 9 21:02:37 2024, Luke, Update, VAC, Steadystate temperature of flanges
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I measured the temperature of the flanges and reconnected the RGA turning on its filament. I then turned off the PID controllers.
Here is a table that has the temperature of the different parts of the vacuum chamber.
Electronics
Temperature (C)
Pressure gauge (Main volume)
81
Main |
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Mon Sep 9 14:27:36 2024, Pooyan, Infrastructure, Computers, Chimay backup attempt
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One ongoing work is to make all lab machines automatically backed-up on Scribe on a daily basis. The updates should be boatable and stored for some time
(potentially a few weeks) on Scribe. Making whole disk images has already been tried for some of the machines with no problems. (e.g., Cymac and WorkStations)
The same thing can not be done with Chimay though, as it currently has one huge RAID-controlled volume that stores all the information (OS, home |
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Mon Sep 9 12:36:45 2024, Michael, Update, Interferometer Simulations, Update on Analysis of Mode Mismatch Minimization in A#
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I have taken a closer look at the solution curve in the mirror parameter space which I have searched, focusing on the "resilience" of specific points, with
the plan to analyze how certain conditions of the interferometer change as we move along this solution curve. |
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Fri Sep 6 14:34:52 2024, Luke , Update, VAC, Heating tape work
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On the 5th I had tried to start baking the vacuum chamber however certain parts of the chamber were getting too hot and causing the controllers to shut
off. So I turned them off so that the next day I could rearrange the temperature probes. I then on the 6th set them up so that instead of overshooting
the temperature they would be a little low in places. |
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Tue Sep 3 18:24:17 2024, Tyler, Update, CDS, Cymac Timing Chassis Issue
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[Tyler, Jon]
The timing chassis used for the cymac has been shut off due to an unknown issue causing its supplied current to fluctuate. All real-time
models will be suspended until a solution is found.
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Tue Sep 3 15:52:56 2024, Luke, Update, VAC, Heater tape initilization
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[Luke, Tyler, Jon]
On the 3rd we set up the pid controllers for the heater tapes and after putting on the insulation we started heating them up. We first brought
it to ~50C and let it stabilize, there was about a 6-7 degree difference between the RGA and the barrel temperature, with the barrel being higher. We then |
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Sun Sep 1 16:17:40 2024, Luke, Update, VAC, Vacuum chamber leak checking and re-applying heating tape
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[Luke, Luis, Cinthia, Michal, Tyler]
On the 26th Cinthia, Michal, and I took off the insolation on the vacuum chamber and re-routed it to include the new RGA volume.
The next day Luis and I finished up the last of the flanges to be attached. We attached the Pirani gauge with a conical reducing nipple to the |
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Thu Aug 29 16:39:34 2024, Luke, Update, VAC, Photos of heater tape 6x
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Tue Aug 27 18:37:40 2024, Luke, Update, Interferometer Simulations, Ringheater model update
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Updated the model to produce a more circular deformation in the HR surface. The first three attachments are from irradiance patterns gotten from ray tracing.
The last is from a pre-defined irradiance pattern. |
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Tue Aug 27 15:01:26 2024, Luke, Update, VAC, RGA line leak testing
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[Luke, Tyler]
On the 27th Tyler and I ran the RGA leak test again with the electron multiplier on. These were the leaks we measured. The chamber's overall pressure
was at ~6e-8 torr. |
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Mon Aug 26 14:42:04 2024, Cynthia , Update, Interferometer Simulations, current status on cavity scan with effects of FROSTI
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I used the code and arm cavity model used for previous O5 study on mirrors and HOM (the pdf of the study and the result can be found at https://dcc.ligo.org/LIGO-G2100878),
but it seems like the result I obtained is different from the study result. Since my cavity scans codes have a large portion of it relying on this code,
I will have to go over the study result and the code to make sure there is no issue with that code itself first. There are also some other updates or issued |
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Fri Aug 23 16:08:32 2024, Luke, Update, VAC, RGA line leak testing
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[Luke, Luis, Jon, Tyler]
On the 22nd Dr. Richardson showed Luis, Tyler and I how to preform a leak test with the RGA. We did the initiall test and found a few leaks two
were particuarly bad highlighted in orenge below. To try and remidy this we planned on replacing the copper gaskests on the leaking flanges. We then began |
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Mon Aug 19 07:11:55 2024, Cynthia, Update, Interferometer Simulations, cavity scans with FROSTI effects
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Fri Aug 16 12:51:46 2024, Luis Martin, Update, VAC, Update on vacuum chamber status
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[Luis, Luke, Tyler]
Vacuum chamber parts were finally received and assembled. After whipping down the parts, the blank was removed from the reducing cross. Then,
the zero-length reducer was attached. Lastly, we installed the T that had the argon leak and RGA. The final pump down showed signs of an improved seal |
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Mon Aug 12 17:09:04 2024, Cynthia , Update, Interferometer Simulations, O4 vs O5 cavity scans with ITM plume guess or ETM
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So far the proposed solution for what to use for O5 ITM mirror for SIS simulations is either the plume guess file or using the O5 ETM mirror for ITM. I
had ran a cavity scan for both of these possibilities and it seems like the results produced are fairly different. The next step is most likely moving
on to adding the Frosti effects including both of the proposed possibilities, and before this, a few confirmations and verifications are needed using similar |
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Mon Aug 12 16:35:30 2024, Luke , Update, , Ringheater modeling Update
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Mon Jul 29 14:30:16 2024, Tyler, Update, Cleanroom, RIN Measurement Set-up
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[Tyler]
I have begun moving parts into the cleanroom for the upcoming FROSTI RIN tests that will be conducted within the next few weeks. While waiting
for the rest of the equipment to arrive to perform the full-scale tests, I have additionally moved the FROSTI under the shelf above the optical table,
where it will stay for the meantime. As always, please use caution when in the cleanroom. Aside from the FROSTI, the IR photodetectors that will be used |
 Mon Aug 12 16:24:34 2024, Tyler, Update, Cleanroom, RIN Measurement Update 1
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[Tyler]
For some preliminary tests, I moved the IR photodetectors outside of the cleanroom and onto the other optical table. The basic goal was
to obtain a signal from both photodetectors. To achieve this, one of the heater cartridges used for early FLIR measurements months ago was hooked up to
a power supply (PS). The PS was set to supply 0.20 A with a voltage of 2.8 V; the corresponding power is thus 0.56 W. With this, I was able to measure |
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Tue Aug 6 13:07:07 2024, Xuejun, Update, Interferometer Simulations,
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[Xuejun]
The width and location of the measured in-air change in temperature profile has been determined to be 0.045m and 0.137m respectively. Subsequently,
a fake irradiance profile was able to be generated that best resembled what the actual irradiance profile could be using this information for testing in
COMSOL. The generated irradiance profile that output the most similar change in temperature profile as the measured in-air profile has been included as |
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Sun Aug 4 09:01:01 2024, Michael, Update, Interferometer Simulations, Update on SRC Mode Mismatch Analysis
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| An update on my analysis to minimize mode mismatch/scattering by introducing toroidal mirrors to the SRC. |
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Fri Aug 2 13:50:22 2024, Shane, Update, CDS, Serial Comm. Test (Agilent Turbo Pump)
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Did a brief communication test with the agilent turbo pump today, to see if we could get serial communications up and running for it. Used a simplified
python script with sockets package to establish a connection and send a simple command to query the pump's operational status. The connection was successful,
and had no issues establishing. The command also sent successfully, and received a response. The response didn't make sense, though, as all the possible |
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Thu Jul 11 21:01:37 2024, Jon, Infrastructure, General, Cable tray installed in 1129
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Today I installed a 10' cable tray in 1129, for permanently routing Ethernet lines to the workstations. It is securely bolted to C-channels in the side
wall and in the center cable tray. |
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Tue Jul 30 07:42:47 2024, Jon, Infrastructure, General, Cable tray installed in 1119
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Yesterday I installed another 5' cable tray in 1119, for permanently routing Ethernet lines to the L-bench. It is securely bolted to the top of the electronics
rack, on one end, and to the top of the glass-door storage cabinet, on the other. This eliminates the need for the cable ramp which previously sat behind
the rack. |
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Thu Mar 21 16:56:42 2024, Tyler, Update, DAQ, RTD Parameter Calibration
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[Jon,Tyler]
We noticed that the RTD temperature readings given on the Cymac were off, and traced the issue to miscalibration in the relationship
between the resistance and temperature of each RTD (Callendar-Van Dusen eqn). Below is the table of values inferred from independent measurements of temperature
and resistance to rectify this problem. This data was then fitted to better determine the coefficients present in the temperature-resistance relation: |
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Mon Mar 25 10:55:33 2024, Tyler, Update, DAQ, RTD Parameter Calibration
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Refitted RTD calibration, neglecting quadratic term:
R_0 (ohm) Alpha (1/C)
RTD 0 79.3962 0.002031
RTD 1 78.2874 0.002530 |
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Tue Mar 26 13:51:56 2024, Tyler, Update, DAQ, RTD Parameter Calibration
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Another re-fit, but this time the quadratic coefficient (beta) is set to 1.003e-6:
R_0 (ohm) Alpha
(1/C)
RTD 0 79.7386 0.001863 |
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Mon Jul 29 13:39:16 2024, Tyler, Update, DAQ, RTD Parameter Calibration
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[Tyler]
Using the data taken during the FROSTI testing at Caltech, I attempted to find a better calibration of the RTD sensors, given our past issues
with inaccurate readings. The fit parameters, alpha and beta, are still all different from the initial values given to us by Fralock (alpha = .003, beta
= 1.003e-6, R_0 was not given), but the true values will differ based on factors such as part geometry.
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Mon Jul 29 12:23:10 2024, Liu, Update, Interferometer Simulations, Update on mechanical resonances of CE BS with stiffener ring
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| Update on mechanical resonances of CE BS with stiffener ring is attached. |
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Mon Jul 29 12:20:56 2024, Liu, Update, Interferometer Simulations, Update on wavefront actuation with astigmatically driven RH for CE
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| Update on wavefront actuation with astigmatically driven RH for CE is attached. |
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Mon Jul 29 12:18:52 2024, Liu, Update, Interferometer Simulations, Update on FROSTI O5 ETM profile optimization
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| Update on FROSTI O5 ETM profile optimization is attached. |
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Fri Jul 26 17:25:42 2024, Jon, Infrastructure, Computers, New workstation ws4 installed in 1129
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Today I installed the second desktop workstation in 1129. The new machine is an Intel NUC13ANHi5, with a 12-Core Intel i5-1340P CPU, 32GB DDR4 RAM, and
a 1TB SSD.
I loaded it with a fresh installation of Debian 12 and installed the LIGO CDS workstation (control room) tools. It is assigned the hostname ws4 |
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Mon Jul 22 18:19:34 2024, Luke, Update, VAC, Zero length reducer stuck bolts
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Today, I borrowed a bolt extractor drill bit from the machine shop to remove some stuck bolts from the zlr. Before starting, I laid down a sheet of aluminum
foil on the work table and wiped down all the tools I was going to use. I began by drilling a small pilot hole and then enlarged it with a 5/32 drill bit.
However, when I attempted to use the bolt extractor, it didn't grip the bolt effectively. Our bolts were too seized, causing the extractor bit to repeatedly |
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Tue Jul 9 18:19:50 2024, Shane, Update, CDS, ADC-DAC loopback testing and IOLAN installation
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[Shane, Jon]
Finished ADC-DAC loopback testing today (see attached xlsx file or access directly here).
All looks well with the first 8 channels, with the gain hovering just under 2. Also edited c1msc model in simulink to add channels 7-15 (the last 8 channels),
and changed the rate back to 64K. See image 1 for the updated c1msc model. The last 8 channels are also looking good and show no problems, with slightly |
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Tue Jul 16 18:43:07 2024, Shane, Update, CDS, ADC-DAC loopback testing and IOLAN installation
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UPDATE:
Follow up ADC-DAC loopback testing now complete, matching all the ADC channels to a single DAC channel, and then matching all the DAC channels
to a single ADC channel (see attached xlsx file or access directly here).
Also note c1msc model file has been updated to include the second set of 16 ADC channels. The newly added channels also have their own filter modules, |
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Mon Jul 15 15:52:40 2024, Michael, Update, Interferometer Simulations, aLIGO locking with varying SRC mirrors and measuring mode mismatch
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Mon Jul 15 15:44:52 2024, Cynthia , Update, Interferometer Simulations, performed cavity scans with thermal effects and ring heater
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Mon Jul 15 14:49:06 2024, Pooyan, Update, Computers, Synology NAS server setup
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Installed a Synology NAS server (Synology RackStation RS1221) in lab room 1129, with host name “scribe” and ip “192.168.1.17”. It is mounted on the rack
and each of its 8 storage bays has a 2TB SSD disk. It will be used to set up automated backups of all the lab machines (e.g., chimay, logrus, megatron).
One shared storage is set on it with SHR-2 as its RAID type. It can tolerate the failure of two disks and has 10.4TB of total capacity. |
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Mon Jul 15 14:28:32 2024, Pooyan, Update, Interferometer Simulations, aLIGO test mass surface profiles
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Created a Google Slides presentation to summarize all the mirror surface map information that we use for simulating interferometers.
A+ expected maps are based on correspondence with G. Billingsley. The estimate for the A+ ITMs will be to take the “as polished” data and add coating
non-uniformity to it. (T2000398) Neither of these are scaled for the precise thickness of the Ti:Ge coatings. |
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Mon Jul 15 13:30:49 2024, Luke , Update, VAC, Problem with 2.75" to 1.33" zero length reducer
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Last Friday while checking the depth of the ZLR I got one of the screws stuck. Today I tried a couple things to get it out. First I tried a few different
pliers to be able to grip lower on the screw this didn't work. So I switched to the other method of drilling a small hole to see if maybe the threads would
pull away from the walls of the hole a bit. This kind of worked as seen in the picture below I was able to remove most of the screw but there is a bit |
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Mon Jul 15 09:36:44 2024, Liu, Update, Interferometer Simulations, ETM Profile Optimization for FROSTI
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This is to optimize the FROSTI heating profile for ETM, by minimizing the residual RMSE of the HR surface deformation after the beam size weighted curvature
is removed by the current RH. The parameters of the profile being explored are the location, width, and total power for the Gaussian Annulus. As shown
in the attached series of plots, the optimal location is 9.9 cm, with a width of 7.7 cm, and a total FROSTI power of 12.7 W (for 1 W of Gaussian beam absorption). |
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Sat Jul 13 15:09:04 2024, Luke, Update, General, Ring heater COMSL model update
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After the feedback from last meeting and Liu's help narrowing down what I should do to improve the model. I made some changes: First with Liu's help
I made the proportions of the test mass and ring heater much more reasonable and parametrized by constants. Second from Cao's paper "FROSTI Nonimaging
Reflector Design" Liu showed me what I should do to define the elliptical mirrors. Third during Friday's modeling/programming meeting walked me through |
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Thu Jul 11 15:53:39 2024, Luke, Update, VAC, RGA line upgrade
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[ Luke, Jon ]
Started work at 11:00
As mentioned in my previous post the RGA was not clearing the table because of a tilt in the cross. So I removed the 90 deg elbow, loosened the |
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Wed Jul 10 17:31:07 2024, Luke, Update, VAC, RGA line disassembly and upgrade
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[ Luke, Cynthia, Michael, Xuesi, Anthony ]
Started work around 12:45
We vented the chamber first and once it reached atmospheric pressure we started taking apart the RGA line. |
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Mon Jul 8 17:01:45 2024, Shane, Update, CDS, New CyMAC internal layout
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[Jon, Shane]
Internal layout of CyMAC has been updated (labeled image attached) to accommodate the replacement of the two ribbon cables. Looking down
on the chassis from the front, and going from left to right, the new placement is as follows: BIO card, DAC adapter board, ADC adapter board, DAC card,
ADC card. NOTE: As part of ADC-DAC loopback testing, we're disconnecting from the FROSTI readout chassis and using the cables to connect directly from |
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Mon Jul 8 12:26:10 2024, Michael, Update, Interferometer Simulations, Minimizing Astigmatic Effects in the SRC of LIGO
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This is the first look and analysis of the effects of astigmatism in the aLIGO optical layout which can lead to mode mismatch and therefore increased losses
into higher order modes. Specifically I am currently looking at measuring the effect of changing the radii of curvature of the SRC mirrors https://docs.google.com/presentation/d/1qhIehqyNukg4g8S2fqfQZz83yr9aB76tEa6fn2J-TrM/edit?usp=sharing |
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Mon Jul 8 10:39:14 2024, Xuejun, Update, FLIR, Average Temperature Profile
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After taking data for each of the individual heater elements, I imported them into python and overlayed them to produce an average temperature profile.
I rotated the 7 of the elements to align with element 1's profile and averaged them out. By setting the range to 28C - 33C (this gave the best visibility
of the heating pattern) it gave the profile attached. |
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Fri Jul 5 14:23:13 2024, Liu, Update, Interferometer Simulations, Engineering drawings for straight edge heater element designs for FROSTI
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Step files and engineering drawings for the straight edge heater element designs have been created in COMSOL and SolidWorks. They are available in the group
Git
Repo. With those, we will initiate a discussion with the ceramics supplier for an estimate of the feasibility and benefits of the straight edge element |
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Fri Jul 5 14:12:32 2024, Liu, Update, Interferometer Simulations, CE BS Mechanical Resonances
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The butterfly and drumhead mechanical modes for the aLIGO BS were calculated in COMSOL. The resonant frequencies for the two acoustic modes are 2.45
kHz and 3.61 kHz, matching the results in reference
for instance.
For a quick projection for the resonant frequencies going from aLIGO to CE, the height and width of the BS are increased assuming |
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Fri Jul 5 13:17:44 2024, Liu, Update, Interferometer Simulations, Four-quadrant FROSTI-like RH for astigmatic thermal actuation for CE optics 7x
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In the CE corner layout design and down selection study, interferometer layouts with large incidence angles on some of the curved optics are being considered,
such as the folding mirrors in the "long crab". This however generates astigmatic beams upon reflection and results in mode mismatches in coupled cavities
that need to be mitigated. Astigmatic thermal actuation for the optics involved is thus essential. One way we are considering is to implement a FROSTI-like |
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Mon Jul 1 15:19:42 2024, Cynthia , Update, Interferometer Simulations, O4 and O5 mirror cavity scans with thermal effect
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Mon Jul 1 11:45:45 2024, Sid, Update, Interferometer Simulations,
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Progress update: Most of last week was spent getting set up with SIS, and learning how to do basic simulations. The goal for this week is to begin reproducing
the methodology from T2000338. I have begun with studying perturbations to mirror curvature and position in a simple FP cavity, but thus far have been
unable to get the same results. |
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Fri Jun 28 18:15:16 2024, Luke, Update, VAC, Vacuum chamber
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We will be configuring the RGA line to remove the spherical cube from the system. Currently our plan for the new design is to connect a 4.5" to 2.75"
Reducing Cross to the gate valve on the vacuum system. It will be orientated vertically with the turbo pump on top coming off the end will be a 90 deg
elbow. On the bottom there will be a 4.5" to 2.75" Zero length reducer attached to that will be a Tee on one side the pressure sensor and the other the |
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Fri Jun 28 10:43:13 2024, Xuejun, Update, Cleanroom, Frosti
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[Xuejun, Tyler]
We moved Frosti into the cleanroom and debugged it to make sure everything was working. One of the DB25 pins broke off at the connector
for element 1 so it needed to be recrimped. Element 6 short circuited but fixed with adjustment to the heater power pin position. We connected the power
and sensor connectors to the power box and recalibrated the RTD sensors.
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Thu Jun 27 13:42:02 2024, Shane, Update, Cleanroom, cleanroom 5 zone particle count measurement
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Here's today's 5 zone measurement of the cleanroom. We're above the limit by a bit in zone three (all three size ranges), likely as a result of the recent
work installing FROSTI, so it could probably use another focused cleaning. Everything else is below the limit. |