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=

Test 1: Adapter Board Connected to Filter Board

• Setup: AI Chassis is powered on. Signal is measured directly from the adapter board. All other ports on the adapter board are connected to the filter board.
• Observation: Two distinct spikes observed at the beginning of the measurement.

Test 2: Adapter Board Disconnected from Filter Board

• Setup: AI Chassis remains powered on. Signal is again measured directly from the adapter board. This time, the remaining ports on the adapter board are not connected to the filter board.
• Observation: Multiple spikes observed, distributed evenly across the entire measurement.

Test 3: Isolation Test with Spare Adapter Board (ongoing)

• Setup: Suspecting the original adapter board may be faulty, a spare adapter board is used for comparison. Signal is measured directly from this spare board.

Update, 04/08/25, Tue 17:30

Took the old adapter board out of the AI chassis and and used it to connect DAC to AA chassis. If no spikes are seen, it means that the glitches are not originating from this board.

Also checked al the previous spikes using the raw data (65536 Hz sample rate). The duration of the glitches are ~1 second, despite the previous guess that they are happening in the Milli-second scale.

Test 4: AI Chassis ground isolation

• Setup: AI Chassis isolated from the ground with readout directly connected to adapter board
• Observation: No spike observed.

Test 5: Ribbon cable check

• Setup: AI Chassis remains isolated from the ground. The signal is measured after the ribbon cable. (Attachment 3)
• Observation: No spike observed.

Test 6: Single ground connection check

• Setup: AI chassis powered on but remains isolated from the frame. The signal is measured from the output of the AI Chassis. (Attachment 1 ,2)
• Observation: No spike observed.

Test 7: Reconnect ribbon cables

• Setup: Reconnect all the ribbon cables, and turned on the AI Chassis while isolated rack
• Observation: No spike observed.

Test 8: Reconnect to rack

• Setup: Reconnect the AI Chassis to the rack.
• Observation: No spike observed.

Test 9: Restore to original position.

• Setup: CLose up the AI Chassis, and put it back to its original location.
• Observation: No spike observed.

[Luke, Ma, Tyler]

The vacuum chamber is currently baking. 

Current state as of 5:00

The gate valve is open, and the filament of the RGA is on. Argon leak is opened

The temperatures are as follows:

PID right barrel upper: 99°C,  RGA volume: 120°C

PID left barrel lower: 123°C, Lid: 92°C

The vacuum chamber has stopped baking. 

Current state as of 12:30, 5/2/2025:

The gate valve is open, and the filament of the RGA is on.

The temperatures were steady at:

PID right: barrel upper: 108°C,  RGA volume: 120°C

PID left: barrel lower: 120°C, Lid: 91°C

All Sorensen power supplies are turned off. The Cymac system is down (All Chassis are down)

If you need more information or if you need to turn them back on please contact Xuesi Ma.

Date and Time: Around 2:20 PM on May 21, 2025

Location and Temperature:

• Back of the room, around the working station: 85.5 °F
• Front of the room, around the doorway: 82.3 °F

Using the configuration in section 2.11.1 in the Sorensen installation and operation manual (attached below), I'm able to remote control the Sorensen power supply.

I use DAC VEXC8 as the external voltage source and a breakout board to match the configuration of connector J3.

I have recorded 7 cycles (attached below), and am now working on analyzing the data.

We currently have the parts for a DB9 connector but need parts for a DB25 connector, where did we get the parts for the DB9 connector? We may be able to use the same company for the DB25 connector.

Also need a cable for the connectors. Find a DB9 to DB9 cable in 1129, not sure if I can disassemble it and use just the cable.

The pressure in the vacuum chamber rises to 2.12e-8 torr, which needs baking.

Date and Time: Around 3:50 PM on June 2, 2025

Location and Temperature:

• Back of the room 1119, around the working station: 86 °F
• Front of the room 1119, around the doorway: 84.1 °F
• Back of the room 1129, around the working station: 78.6 °F
• Front of the room 1129, around the doorway: 78.3 °F
• In the hallway in front of room 1119: 75.2 °F

By measuring the resistance of the ladder, I obtained a graph of resistance as a function of voltage.
All the heater elements behave consistently, showing only a small standard deviation.
However, heater element 5 shows a significantly larger standard deviation.
Upon examining the initial ladder graph, I noticed that the resistance of heater element 5 increases following a power outage that resets the system.
At this point, I am unsure why this behavior occurs.

CYMAC Remote Control Cable Assembly

Cable Functions

The custom cable assembly serves two primary functions:

Note: All connections are verified with a multimeter.

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.