cleaning cleanroom and particle count

• 5:10 pm: ran zero count test on particle counter
• 5:14 pm: started particle count

  NOTE: initial counts are significantly above allowed limit. ~10 times larger than ISO class 5 standard in the smallest size range. Realized partway through ceiling tile changes that the power/lights for some of the hepa fans in the ceiling frame had been turned off. May explain this high number. Have since turned fans back back on.

  • zone 3:
    • 0.3 u: 109208
    • 0.5 u: 16337
    • 1.0 u: 581
• zone 4:
  • 0.3 u: 51340
  • 0.5 u: 9228
  • 1.0 u: 581
• 5:33 pm: started replacing ceiling tiles
• 6:25 pm: began surface check and wipedown, including softwalls
• 6:33 pm: started vacuuming the floor
• 6:45 pm: finished vacuuming the floor
• 6:45 pm: started mopping the floor
• 6:50 pm: finished mopping the floor
• 6:52 pm: started cleaning the buckets
• 6:53 pm: started mopping with IPA wipes
• 6:58 pm: finished mopping with IPA wipes
• 6:59 pm: changed sticky floor mats
• 7:00 pm: started particle count
  • zone 3:
    • 0.3 u: 5404
    • 0.5 u: 1413
    • 1.0 u: 41
• zone 4:
  • 0.3 u: 1704
  • 0.5 u: 332
  • 1.0 u: 166

Group Meeting slides for Non-deterministic Heater Response.

I conducted separate tests on the '5015' and '3010a'. When powered individually, the '5015' outputs a signal at 33.55 MHz with an amplitude of 608 mV. It draws 1 A of current from the power source. The input signal for the '3010a' is 33.54 MHz with an amplitude of 670 mV (peak-to-peak) and a 15 mV DC offset. The output signal from channel 1 is a 65.5 kHz square wave with an amplitude of 3.28 V. The '3010a' draws 0.1 A of current.

Both the '5015' and '3010a' work fine when powered separately. However, when both are powered together, the power source behaves as if there is a short circuit. The current theory is that the switch or breaker is tripping, as it has a 1 A current rating. Since the combined current demand of both devices exceeds 1 A, this may be causing the issue.

Slides for 10/16/2024 Group Meeting

[Ma, Cece, Luke, Mary, Shane]

On Friday (Jan 24), we installed the heater elements on the stand. The heater elements are arranged from 1 to 8, oriented from right to left as shown in Attachment 1. Each wire has been labeled according to its corresponding element number and type (e.g., RTD connections, heater connections).

Note: We currently do not have enough PEEK zip ties, so standard zip ties have been used temporarily. These must be replaced with PEEK zip ties before the setup is placed in the vacuum chamber.

[Ma]

Installed all the pins to the peek DB 25 connectors

[Ma] Wed 1/29/2025

No short circuit between heater element ✓

No short circuit to ground on any pin ✓

No short circuit between connectors ✓

[Ma]

changed all zip ties to peek zip ties, and grouped wires together. The setup is ready to go into the chamber.

[Ma, Pooyan, Tyler]

On Friday, we connected the vacuum chamber with the Cymac.

https://docs.google.com/presentation/d/1WiV2VqS0BzXNCK6VYYQ-Ty8xlHnzXatQaFbMf1-0rsY/edit?usp=sharing

1424039912.625576 2025/02/19 22:38:14 UTC Time start

24V 2.8A right after start all 8 elements

1424044804.902443 2025/02/19 23:59:46 UTC Time stop

24V 1.8A right before stop all 8 elements

0.1A right before start and right after stop

note: turned on briefly to check current right before stop

2/20 RGA Scan

spikes??

1424129207.857777 2025/02/20 23:26:29 UTC Time start

24V 2.9A right after start all 8 elements

1424140789.856096 2025/02/21 02:39:31 UTC Time stop

24V 1.7A right before stop all 8 elements

0.1A right before start and right after stop

2025/02/21 02:43:19 UTC

Main chamber pressure: 1.54e-8

RGA chamber pressure:5.06e-9

spikes are due to loose connection between connectors.

1424210410.173863 2025/02/21 21:59:52 UTC Time start

24V 2.9A right after start all 8 elements

1424218357.96404 2025/02/22 00:12:19 UTC Time stop

24V 1.7A right before stop all 8 elements

each elements: 0.3A (0.2A increment)(all)

0.1A right before start and right before stop

2/24 RGA Scan

1424467918.129082 2025/02/24 21:31:40 UTC Time start

12V 2A right after start all 8 elements

1424478936.635821 2025/02/25 00:35:18 UTC Time stop

12V 1.6A right before stop all 8 elements

each elements: 0.4A (0.2A increment)(all)

0.2A right before start

rise time: A(1-exp(-t/tau))+B

fall time: Aexp(-t/tau) +B

1424564097.243212 2025/02/26 00:14:39 UTC Time start

12V 2A right after start all 8 elements

1424564478.079428 2025/02/26 00:21:00 UTC Time stop

12V 1.8A right before stop all 8 elements

1424564832.211584 2025/02/26 00:26:54 UTC Time start

12V 1.9A right after start all 8 elements

1424565208.359935 2025/02/26 00:33:10 UTC Time stop

12V 1.8A right before stop all 8 elements

1424565573.565066 2025/02/26 00:39:15 UTC Time start

12V 1.8A right after start all 8 elements

1424565931.242394 2025/02/26 00:45:13 UTC Time stop

12V 1.7A right before stop all 8 elements

1424566292.67104 2025/02/26 00:51:14 UTC Time start

12V 1.8A right after start all 8 elements

1424566648.619952 2025/02/26 00:57:10 UTC Time stop

12V 1.7A right before stop all 8 elements

1424566996.312246 2025/02/26 01:02:58 UTC Time start

12V 1.8A right after start all 8 elements

1424567381.748943 2025/02/26 01:09:23 UTC Time stop

12V 1.7A right before stop all 8 elements

1424567756.528736 2025/02/26 01:15:38 UTC Time start

12V 1.7A right after start all 8 elements

0.2A right before start

spikes!?

1424643001.864687 2025/02/26 22:09:43 UTC

change c_0(VEXC0 & VCXC0) to 2V (why is it on 5V ?)

2025/02/26 22:18:51 UTC

Main chamber pressure:5.92e-9

RGA chamber pressure:1.98e-9

1424650528.240947 2025/02/27 00:15:10 UTC Time start (increase voltage)

24V 2.1A right after start all 8 elements

disconnect and reconnect (exc 1-4)(out 9-12) & (exc 5-8)(out 13-16)

2025/02/27 19:34:26 UTC

Main chamber pressure:1.34e-8

RGA chamber pressure:4.33e-9

Main chamber temp: 29

RGA chamber temp:29

2025/02/28 18:02:29 UTC

Main chamber pressure:1.05e-8

RGA chamber pressure:3.53e-9

Main chamber temp: 29

RGA chamber temp:30

1424801097.374902 2025/02/28 18:04:39 UTC Time stop

24V 1.8A right before stop all 8 elements

0.1A right after stop

1424827460.71372 2025/03/01 01:24:02 UTC Time start

24V 2.9A right after start all 8 elements

0.1A right before start

2025/03/01 01:25:34 UTC

Main chamber pressure:5.98e-9

RGA chamber pressure:2.06e-9

Main chamber temp:27

RGA chamber temp:27

2025/03/03 20:28:03 UTC

Main chamber pressure:7.8e-9

RGA chamber pressure:2.64e-9

Main chamber temp:27

RGA chamber temp:27

Spikes Appear Again, need to address it systematically.

Power on and off before reaching steady state ✔

At 12V, the rise and fall time of heater elements are different from 24V.

Initial guess is due to temperature in the chamber. However, it does not seem to be the case, 24V with 30c have the same hall time as 24V at lower temperature.

Attached are some graphs for rise and fall time

After a weekend of powering on, the main chamber pressure stabilized in the UHV region.

Temperature in the chamber seems also not to change.

Continue investigation in the spikes

Pulsed ADC with a function generator and find no spikes. Rules out ADC for causing the spikes

Loopback test that bypasses the FROSTI Chassis shows spikes (spikes happened on all channels at the same time)

Next step is to bypass the AI Chassis to find the source of the spikes

The result from AI Chassis bypass test showed that the AI Chassis may be the problem. There are no spikes from DAC's direct output.

All chassis except timing chassis are turned off. Power supplies for 24V, 18V, and -18V are turned off

The AI chassis has been taken out of the rack for further inspection

https://dcc.ligo.org/LIGO-E2300117

https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?.submit=Identifier&docid=D2300124&version=

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.

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.

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 well as the change in temperature profile it produced on the blackbody screen "test mass" model in COMSOL.

FLIR: After some adjustments, the plot generated from the FLIR measurements look much more symmetric (see attachment). There are more included grid points, which smooths out the curve as compared to last week.

Red Pitaya: It looks like a new OS update was released for the RP, which includes a new Python API (was previously only available in C). I'm going to try and update the one we have currently running in lab.

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.

After initial analysis from last week on a single RTD, I then extended to looking at all 8 in series with R_ref (set to 1 kOhm). Shown below are the edge cases for the setup:

• RTDs are all at ambient lab temperature. This would correspond to a minimum resistance value.
• RTDs all read out 400 C. This gives the maximum resistance value.

The results show that indeed only a few mA of current is drawn even at room temperature (a little above 5.5 mA), and this will continue to decrease with increasing temperature. The voltage across a single terminal, at a maximum, is only about 5.4 V.

Below are a basic diagram of what the RTD measurement circuit logically looks like and an example schematic of the actual wiring. The schematic wiring will be placed internally into a chassis, connected to the RTDs via DB25 cable.

[Tyler, Shane, Mohak, Cynthia, Luke, Michael, Luis]

The tabletops have been attached to the workbench frames. Unfortunately, one of the tabletops came out of the box with a large scratch and small dent in the middle. One of the electric top shelves is ready to be attached to the undamaged table, but the other is yet to be opened. Assembly will be completed Wednesday morning.

The workbenches are now completely assembled and put into their final places. Additionally, the tool chest has been moved.

Below is the current state of the RTD readout chassis wiring. Initial continuity tests seem good, will run through one more time to confirm.

I performed another continuity test on the RTD chassis wiring, and everything seems to be set up correctly. The chassis should be ready for installation.

After updating the wiring in the RTD Chassis, a signal is now seen at each ADC input. However, there seems to be a discrepancy between the voltages I measured out with the multimeter (see below). Next steps include:

• Finish final debugging
• Calibrate ADC inputs with known voltage source (likely to use DAC).

Voltage Readings:

RTD 1: 0.576 V

RTD 2: 0.578 V

RTD 3: 0.598 V

RTD 4: 0.563 V

RTD 5: 0.477 V

RTD 6: 0.463 V

RTD 7: 0.456 V

RTD 8: 0.491 V

Reference Resistor: 5.463 V

Total Voltage: 9.665 V

After further modification of the RTD readout chassis (i.e. adding resistors, placing reference resistor in front of RTDs), here are the following direct measurements:

RTD 1: 0.484 V

RTD 2: 0.486 V

RTD 3: 0.503 V

RTD 4: 0.474 V

RTD 5: 0.495 V

RTD 6: 0.483 V

RTD 7: 0.476 V

RTD 8: 0.510 V

Reference: 5.847 V

Here are the Cymac signal readings:

RTD 1: 74

RTD 2: 67

RTD 3: 73

RTD 4: 45

RTD 5: 82

RTD 6: 75

RTD 7: 70

RTD 8: 71

Reference: 884

The one (possible) discrepancy here is the readout for RTD 4 via Cymac, since it's signal reading is ~30 counts lower than the others. I do not believe this is a wiring issue due to the direct measurements taken.

Below is the proposed schematic for FROSTI optical testing, chosen so enough space is allotted for prototype assembly.

Steps to be taken include:

1. Reconstruct FLIR staging apparatus
2. Move test mass stand-in to cleanroom
3. Mark FLIR camera position on cleanroom optical table at correct distance
4. Run ethernet cable into cleanroom
5. Move FLIR aside to allow for more assembly space
6. Upon assembly completion, reposition FLIR onto optical table again

Tentative plan is to begin setup early next week.

I reproduced Cao's CE beamsplitter code (see below for example plots). I received the current info on the beamsplitter parameters for A+ and A# from GariLynn also. The next steps are to perform a similar power loss analysis on the anticipated A# beamsplitter.

The replacement door for the HEPA garment cabinet arrived last week, and was installed on Thursday. However, it looks like there's a small gap between the door and where the hinge is attached to the cabinet frame. No screws were provided with the replacement door. If we want to perform any adjustments, we have to be very careful; the screws break very easily.

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.

Heater 1= 72.8; 80.6

Heater 2= 69.5; 80.8

Heater 3= 70; 83.2

Heater 4= 70.6; 78.7

Heater 5= 69.9; 80.6

Heater 6= 71.1; 78.2

Heater 7= 68.5; 76.8

Heater 8= 70.1; 82.8

FROSTI assembly was completed today. The RTD and power wires were terminated at the DB-25 connectors and the legs were put on. It is currently placed in front of the stand-in test mass (~5 cm away). The FLIR has also been moved back to it's nominal position. As of now, it appears there are some shorts within the power cabling. This will be a focus of tomorrow's work.

Upon finishing the FROSTI assembly last week, we ran into some electrical issues. An electrical short was found between two of the d-sub pins (2 and 8). It appears that the pins were somehow coming into contact with the aluminum surrounding them. This was causing the power supply to trip. The issue was seemingly fixed by adjusting the positioning of the cabling leading out of the reflector. When handling the device in the future, please make sure to keep the wiring as undisturbed as possible. The setup is rather fragile, and moving the cabling around could potentially reintroduce a short like this.

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:

       R_0 (ohm)   Alpha    Beta

RTD 0   80.8674   0.001315   4.273e-6

RTD 1   79.5704   0.001887   3.7873e-6

RTD 2   81.7334   0.002014   2.1724e-6

RTD 3   74.3060   0.003677   3.6022e-8

RTD 4   81.1350   0.001761   2.3598e-6

RTD 5   77.9610   0.002423   -7.5192e-7

RTD 6   78.7980   0.001373   6.2909e-6

RTD 7   83.8616   0.001890   3.3529e-6