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 a signal using the Red Pitaya, the device that will be used for following RIN measurements.

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 for the test are delicate and costly to replace.

[ 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 bolt securing the Tee to the ZLR, and removed the cross from the gate valve. I then spun around the Tee on the bottom so that the cal leak would be pointing in the right direction and connected the rotating 2.75" flange of the cross to the gate valve. I then added the small turbo pump to the top of the cross. 

Then with the help of Dr. Richardson, we made some adjustments to how the Tee was oriented with respect to the cross and how the cross was with respect to the table. So that the cal leak and RGA would fit on the table. After that we made some changes to the bolting of the ZLR to reducing cross replacing the 2.00" bolts and nuts with 1.75" bolts and nut plates. We did face some difficulty with half of the 2.00" bolts which required a bit of torque to get them out. 

Finished work at 2:20 

Things to do:

Before we start pumping down the system again Dr. Richardson wanted two other changes to be made. To replace the 2.75" to 1.33" conical reducer with a zero length reducer. He also wants the bolts that hold the main turbo pump to be replaced with nut plates. 

I plan on starting this work on Friday (7/12) before pumping down over the weekend

[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 taking the two problem flanges off, but seven of the eight bolts holding on the turbo pump were over tightened and had seized. So after we got them off we postponed the rest of the work to the next day.

On the 23nd Luis and I reattached the badly leaking flanges with new copper gaskets. We then preformed the Helium leak test with the RGA. As seen in the table below we weren't able to majorly changed the leaks in the two flanges.

[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. 

[ 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.

We removed the parts in this order: Calibrated leak, RGA, Pressure gauge, 2.75" Blank on Tee, 2.75" Tee, all 1.33" Blanks on the cube, 4.5" feed through port, and finally the cube. Everything went smoothly after every part was taken off we covered the ends in Aluminum foil to maintain cleanliness. 

We then started the assembly of the new line. The parts were added in this order: Reducing cross, ZLR, Tee, Cal leak, RGA, 90 deg Elbow, and Pressure sensor.

We left off the Turbo pump as of now because we weren't able to find a 1" post not in use and we didn't want to put too much weight on the cross. We also noticed that the RGA might not fit on its probes because of a slight tilt to the cross and by extension the Tee. If this ends up being a problem we might need to remove all the parts connected to the cross so that we can reposition it so that the 2.75" rotating flange is connected to the gate valve.

Ended work around 4:00

1. Run a second RGA degas cycle, but next time with the main volume valved off with only the RGA volume being pumped (through the bypass line). This will prevent "boiled off" particulate from entering the main chamber and will also increase the pumping rate for the RGA volume, reducing the amount of particulate that resettles on the RGA filament.
   
   
2. I also noticed that the SRS manual states that the filament is designed to be long-lived and it is recommended to leave it on any time the RGA is on. By leaving the filament on all the time (i.e., hot), we could reduce the amount of particulate that is evidently settling on it between scans. I am checking whether LIGO Lab does this in their own chambers.

As a follow up ELOG 261, I have received advice from one of the vacuum experts at LIGO Hanford on best practices for our RGA:

1. For future RGA degassing, definitely keep the main volume isolated, since it could contaminate the main volume with everything that just got cooked off of the filament. So the procedure should be to (i) close both gate valves, (ii) ensure the angle valve on the bypass line is open, (iii) initiate the degas cycle on the RGA, (iv) pump the RGA volume through the bypass line, until its pressure returns to its pre-degas level.

2. Repeated degassing of the filament will definitely wear it down much faster, so do this operation sparingly.

3. As long as the pressure of the RGA volume is in the UHV range (~1e-9 torr), best practice is to leave the filament on. This keeps it hot which helps prevent particulate from settling on it. However the electron multiplier should stay off when not actively taking scans, as it will wear down if left on all the time.

[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.

The following images compare the RGA scans from 9/23/24, after the first bake with the new vacuum system, with those from 3/14/24, after bake 12 with the old system.

The first image shows a graph of the raw data and includes the calibrated leak for both curves. As we can see, our new system meets LIGO standards of cleanliness.

The second graph contains the plot of the normalized data.

The following figure displays data acquired on 10/09, and it shows that we are no longer below the cleanliness standard. Also, the system's pressure went up to 1.9x10^-8 Torr (approximately 7x10^-9 Torr previously). This might be due to a leak somewhere in the system. More tests will be performed later.

[Luke, Luis, Mary, Ma]

On 10/22/24 Luke, Ma, Mary and myself ran a RGA scan, the results are displayed below. The overall pressure of the vacuum was 2.0e-8 and the temperature readings were 26C for the RGA and 25C for the main volume.

As we can see, the vacuum is passing cleanliness standards again.

Preliminary RTD calculations are shown below, given an input of 10 V and desiring a few mA of current. It looks like R_ref should be at least 1 kOhm (refer to plots/circuit below), keeping in mind we need to have <10 V input for the ADC.

RP: The Red Pitaya Software was updated to OS 2.00. All examples on the RP website should run without issue.

Changed the pre filter inside of the 3 stage HEPA system next to the soldering station. It was rather dirty and I have attached images with a clean filter on the left and the used one on the right. I reset the pre filter age on the system. I tried to see if I could tell if the HEPA filter was dirty but I could not see it. I did not reset the age of the HEPA or UV stations. They are currently 378 days old.

With the new change in wiring configuration described in elog 136, we tried to power up the heaters for baking the vacuum chamber again.

1. Evidence of smoke originating from CoolSkin insulation

We then removed most of the CoolSkin insulation on the Pump and RGA lines ( apart from the one around the flexible bypass line connecting the two ) (see image Pumpline_afterRemoveInsul and RGAline_afterRemoeInsul) . Upon removal of the insulation, we noticed that the insulating foam melted onto the heating tape (see image MeltedInsulation1 and MeltedInsulation2). This is the first indication that the smoke had most likely coming from the insulating foam itself

Once we started baking, upon reaching 80 degree range. We observed no smoke at the location that we removed the insulation. However, We observed smoked coming from underneath the insulation around the flexible pipe, and not from the velcro areas.

2. The heaters still trip our power

On Thursday we installed the power conditioning/distribution equipment and networking equipment in the new 1129 rack. The hardware is identical to the setup in the 1119 rack and includes:

• Tripp Lite SU5KRT3UTF - 208V, 5kVA on-line UPS with 120V transformer
• CyberPower PDU20M2F12R - metered power distribution unit, (14) NEMA 5-20R
• Ubiquiti USW-Pro-48 - 48 port 10Gbps network switch

The UPS is connected to a 208V NEMA 6-30R outlet in the overhead cable tray, which is on the building's "standby" (backup power) circuit. An 8-ft L6-30 extension cord has been ordered to permanently run the power cable through the cable tray.

The network switch will be connected to a Cat6 cable that was recently run by ITS from the 1119 rack, allowing the lab's LAN to be extended into 1129. This Ethernet link remains to be tested.

• I was able to plot the first graph for a result between the six different positions on the screen, for now we can see the behavior of the heater temperature in a Gaussian graph with combination data between the six files.
• To do: Tyler gave me some ideas today to improve the plot. So I'm going to change the code to have insulation on the values for just the heater ("insulation") and I'm going to plot after this insulation data as well I'm going to get more data and compare with more data for the same position.
• I was using the data than I got last week and I shared on Elog (151) and we can see on this quote

Today I brought in a fresh supply of zip ties (we now have 1500 in the tool chest) and used them to permanentize the cable routing for the gauges, pumps, and RGA.

I also brought and installed a 3-foot 15A extension cable for powering the scroll pump. Installing the cable required shutting down the pumps, which I did and then reverted via the following procedure:

1. Close the 4.5" gate valve, 2.75" gate valve, and the bypass line angle valve.
2. Shut down the turbo pump.
3. Shut down the scroll pump.
4. Unplug the scroll pump and install the extension cable.
5. Power on the scroll pump.
6. Power on the turbo pump.
7. Open all three valves.

Incidentally, before I started, I noticed that the pressure in the main volume had reached 7E-7 torr, which is lower than the pressures seen last week. The system quickly returned to this pressure after I restarted the pumps.

Jon, Cao

Today we raised the height of the shelf overhanging the cleanroom laser table by 8 inches. This was done to create more vertical clearance between the top-loading vacuum chamber and the bottom of the shelf. The added clearance should make both removing the chamber lid and inserting large parts easier.

The procedure required unmounting the shelf and removing all eight vertical support posts (1" x 1" x 18.5" pieces of 80/20 unistrut). The support posts were taken to the machine shop and cut, retapped, and cleaned (coarsely, with IPA wipes) prior to reinstallation. We took care to minimize the contamination introduced into the cleanroom, but some amount of particulate from disturbing the shelf was unavoidable.

This work is completed, and the cleanroom is now ready for final cleaning (HEPA vac, mopping, and wiping down of all surfaces including the softwalls).

The FLIR and test mass stand-in have been transferred into the cleanroom. A software test will be run as soon as we get an ethernet cable long enough to reach into the cleanroom where the camera is set up. Once this is finished, the FLIR will be moved aside for construction of the FROSTI! When completed, the camera will be placed back into position for in-air optical testing.

There were no issues with the physical replacement of the post, except that the fork clamp on the post needs to be on one of the perpendicular, not diagonal, axes in order to be secure. I chose the front axis (towards the screen) as before in order to easily access the alignment knobs.

To align, I followed the same process as last time except for a more purposeful original rough alignment. For alignment purposes, the visual camera was used. For the first rough alignment, I pulled the camera as far back as possible on the x axis (with the z axis roughly centered), then moved the entire stage setup back until I could just see both the top and bottom edge of the screen. Then, I set the z-axis to an extreme in order to use the edge of the screen to align the rotational and y-axis pieces for the fine alignment.

For the fine alignment, starting with the z and x axis at extremes, I began by aligning the rotational axis. To do this, I used the gaps between the top of the screen and the camera window on the far left and right of the image. When these gaps were equal I knew the rotation was adequately set. Then, I set the y-axis so that the pattern was centered. If the gaps were no longer even, I redid the rotation alignment and ditto with the y axis until both were set. This resulted in a rotation of about two degrees and a y axis at just under 3.5.

To set the z and x axis, I centered the z-axis using the top and bottom of the screen, which should both be visible if the rough alignment was done correctly. Then, I adjusted the x axis by pushing it forward until the top and bottom of the screen were just out of the frame. As with the rotational and y-axis, I iteratively fine tuned the x and z axis until both the image was centered in the z axis and only the screen was in view. This resulted in a z-axis value of just over 5.5 and an x axis value of nearly 1.75.

Pictures are included of all alignment knobs and the new post/stage setup!

Today I fixed the final bit related to the nitrogen gas tank, which is to apply sealing tape to M-NPT connector of the hose to prevent leakage (file: AirGunSealed.jpg)
After application of the tape, no audible leak can be heard from connection between the hose and the air gun.

The general operating procedure for the gas tank is as following:

1. Turn the regulator (blue handle) anti-clockwise still it's loose
2. Turn the valve on nitrogen as tank anti-clockwise, immediately the RHS meter of the regulator would jump to approx 2000 psi. This is the standard pressure for high pressure gas tank
3. Turn the regulator clock-wise slowly until the pressure one the LHS meter face reads approx 60 psi. This is sufficient for drying parts with. At this point, the flow pressure still should register zero
4. Press the trigger on the air gun, a high pressure air flow should come out and the flow meter should increase
5. When finished, close the gas tank valve, turn the regulator anti-clockwise, then press the air gun trigger to release gas left in the hose/gun

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 and and the static IP address 192.168.1.19 on the local lab network. Like the other CDS workstations, there is just one user account accessible with the usual credentials.

The machine is fully set up and ready for use.

Set-up of the first CDS workstation for 1129, ws3, is complete and the machine is ready for use. The login credentials are the same as the other lab machines.

All that now remains is to install a permanent cable tray for running the new Ethernet cables between the electronics rack and bench (they are currently dangling from the suspended lights).

I delivered new NEMA 5-15 (120V / 15 A) power cables to the lab for the following items:

• WS2 (cleanroom) cart - 10ft cable
• Electronics workbench overhead LED - 10ft cable
• Both PI heater controller sets - (2) 6ft cables

I installed the new cables on the WS2 cart and the workbench myself, and left the two 6ft cables (as pictured below) for Aiden to install on the PID controllers after the current bake is finished.

[Pamella]

Yesterday, I did a new data collection. I could get a better data in this time and I realized than I need use some angle on the reflector for got a better shot. I need do that because the FLIR camera just is able to get the triangle shape for complete if I keep exactly in same line for center point on the camera but for the data now I need move the refletor to go up and go down. So wasn't working very well if I keep the reflector without angle.

Now I am using the refletor with a angle. In the more high part I turn the mask for look the table and in the lower part I turn the mask to look up. I attached a photo below for this configuration. Also the processes to get the data was the same than I using last time, the only diference is now I just moved the pillar after get data for high position and lower position for the same reference point on the triangle shape.

Note: In most data it is impossible to keep the same parameter for current, voltage and temperature. Most have a small variation but not a big difference. For example: I got the temperature in the first position 46.8 °C and in the second position I got 47.1 °C, it's just an example. It's just so we know that we don't have the exact same parameters all the time. In my opinion this is not a problem because it is just a small variation.

The process to get data

• 09:35 am: Turned on the device (current on). I wanted for 30 minutes before start get data.
• 10:05 am: Started taking snap on position one (Reference point: -0.10, 0.050). Parameters:0.11A,1.7V,46.8°C
• I took four snap on the same position for compare after on data analyzes. I just wanted one minute break between the snaps. I did the same for every position.
• 10:15 am: Started taking snap on position two (Reference point:-0.10,-0.050 ). Parameters: 0.11A,1.7V,47.1° C
• 10:22 am: Started taking snap on position three (Reference point:0.00 ,0.050). Parameters: 0.11A,1.6V,48.1°C
• 10:26 am: Started taking snap on position four (Reference point: 0.00,-0.050). Parameters:0.11A,1.6V,48 °C
• 10:32 am: Started taking snap on position five (Reference point: 0.05,-0.050). Parameters:0.11A, 1.6V, 48°C
• 10:37 am: Started taking snap on position six (Reference point: 0.05,0.050). Parameters: 0.11A,1.7V,47.6 °C
• We can see in the photos attached below every position also I am working in the analyzes.

Dr. Richardson installed the new cabinet outside the room for the PPI equipments, and then I wiped all surfaces inside and outside of the new cabinet.

Dr.Richardson and I have finished organizing the PPI within the new cabinet. Also we have new supplies of gloves, and will likely have more supplies for other PPIs soon.

Aiden 3D printed a new bridge for the heater and I installed the new bridge yesterday.

I started collecting data to plot a calibration with the heater. I'm doing measurements with current and the thermocouple (thermometer) to compare with FLIR measurements and have a good calibration.

It should be noted that we can not have the zero length reducer and the gate valve on the same arm as they both have blind tapped holes. We need to decide if we want the gate valve or not as if we do, we will need to use the 3 inch long reducer.

Important Measurements:

From the back of the flange to the back of the RGA: 25.25 in

Height from bottom of the blank to the bottom of the chamber: 2.75 in

Change the 3D mask
• Started removing the old mask in the reflector.
• Started cutting the new aluminum lid for the new 3D mask and assembling in the 3D mask.
• Started doing the new cable connections for the light.
• Started testing the resistance in the new cable connections. The multimeter show us 14.2 Ω.
• Started attaching the mask with the light and the thermometer sensor.
• Started assembling the 3D mask in the reflector.
• Started the initial tests.
• 2:00 pm: Started testing the new mask. Parameters: 1.4 V 0.1A and 27 C
• 2:38 pm: Started taking snap. Final parameters:1.4 V 0.1A and Temperature: 39.9 C
• Started doing some adjustments in the triangles shapes for the futures tests.

Today we started re-configuring the vacuum chamber components.

Particle count
• 10:45 am : Starting the particle count in the clean room.
• 11:13 am : Finished the particle count in the clean room.
• Zone 3 :
  • 0.3 u: 2535
  • 0.5 u: 1413
  • 1.0 u: 789
• Zone 4 :
  • 0.3 u: 457
  • 0.5 u: 290
  • 1.0 u: 207
  Starting the reconfiguration.
  • 11:21 am: Started removing up-to-air valve
  • 11:30 am: Finished removing up-to-air valve.
  • 11:33 am: Started removing calibrated Ar Leak and the elbow.
  • 11:35 am: Finished removing calibrated Ar Leak and started assembling the up-to-air valve.
  • 11:47 am: Finished assembling up-to-air valve.
  • 11:48 am: Started removing magnetron gauge.
  • 11:55 am: Finished removing magnetron gauge.
  • 11:57 am: Started installing the elbow and calibrated Ar Leak and started removing the RGA probe
  • 12:13 pm: Finished installing the elbow and calibrated Ar Leak.
  • 12:20 pm: Break for lunch.
  • 01:25 pm: Come back from lunch break.
  • 01:30 pm: Started removing RGA line.
  • 01:39 pm: Finished removing RGA line.
  • 01:39 pm: Started removing gate valve [RGA line] and finished removing gate valve.
  • 02:00 pm: Started installing gate valve in the new position.
  • 02:08 pm: Fished installing gate valve [RGA line].
  • 02:09 pm: Checked the screws in the elbow to gate valve. [RGA line].
  • 02:28 pm: Finished checking the screws in the elbow to gate valve [RGA line].
  • 02:29 pm: Started installing RGA line.
  • 02:39 pm: Finished installing RGA line.
  • 02:50 pm: Started installing magnetron gauge.(In this part we assembled gauge with the used gasket)
  • 03:02 pm: Finished installing magnetron gauge.
  • 03:04 pm: Started installing RGA probe [RGA line].
  • 03:13 pm: Finished installing RGA probe [RGA line].
  • 03:15 pm: Connected the cables to the magnetron gauge.
  • 03:20 pm: Started the testing in the vacuum chamber.
  • 04:30 pm: Started installing the RGA 200 and connected the cables (power cable and DB9 cable).
  • 04:52 pm: Finished installing the RGA 200 and connected the cables (power cable and DB9 cable).
  • 04:53 pm: Started testing the RGA connections. Logrus is able to recognize and connect to RGA unit. We are leaving the turbo pump on for a few hours before checking back for pressure readouts.
  • 05:00 pm : Starting the particle count in the clean room.
    1. Zone 3 :
       • 0.3 u: 2244
       • 0.5 u: 997
       • 1.0 u: 207
    2. Zone 4 :
       • 0.3 u: 2993
       • 0.5 u: 1579
       • 1.0 u: 498
  • 05:30 pm : Finished the particle count in the clean room.
  • 05:34 pm: Test pressure readout from the gauges.
    1. Channel 1 : 1.06E-5 mbar
    2. Channel 2 :8.89E-6 mbar
    3. Channel 3 :5.0E-4 mbar
  • 05:59 pm: Test pressure readout from the gauges.
    1. Channel 1: 9.09E-6 mbar
    2. Channel 2: 7.75E-6 mbar
    3. Channel 3: 5.0E-4 mbar