 Wed Apr 12 16:13:19 2023, Cao, Physics, VAC, Vacuum prep and installation 
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Aiden, Pamella, Peter, Shane, Cao
Today we started vacuum chamber assembly work
10:16 am: Particle count measurement of clean
room
10:34 am: Particle counting finished: meets ISO 5 standard
Zone 3 :
0.3 u: 3159
0.5 u: 789
1.0 u: 83
Zone 4 :
0.3 u: 498
0.5 u: 41
1.0 u: 0
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Wed Jun 19 18:45:14 2024, Luke, Update, , Vacuum chamber reassembly
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[Luke, Aiden, Mohak , Tyler]
On Tuesday we had the silver screws for the spherical cube shortened by a quarter of an inch so that they would fit into
the gate valve. We then attached the spherical cube to the vacuum chamber.
On Wednesday we finished assembling the RGA line and the main turbo pump.
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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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Tue Jun 25 17:19:42 2024, Luke, Update, VAC, Vacuum chamber leak checking
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Currently our main leak is in the RGA line. We found this by closing the gate valve from the main volume to see if which side was leaking more.
After
identifying this we are pumping down the main volume to see how low it can go the third attachment was taken at 4:16 6/25/24. Pumping started around 3:15.
We have not been able to find exactly which flange is leaking, but our guess is on the small blanks and where the cube attaches to the gate valve |
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Wed Jun 26 16:39:34 2024, Luke, Update, VAC, Vacuum chamber leak checking
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On Tuesday I had isolated the main volume and let it pump down over-night. Today, Wednesday, I checked it and it had only gone down by a small amount compared
to when I left it on Tuesday.
I then proceeded to tighten down the bolts attaching the tubo-pump to the zero-length reducer while it was under vacuum.
This caused the pressure to drop down a few orders of magnitude. |
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Tue Feb 28 13:53:17 2023, Pamella, Update, General, Vacuum chamber cleaning
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Pamella, Dr. Richardson and Dr.Cao finished checking and cleaning the interior of the chamber, chamber lid, and exterior of the chamber with Vectra Alpha
wipes, IPA and in some parts we used acetone . We flip the chamber and put chamber on the table again. A picture of the specific situation is attached
below. The next step from here would be to finish the cleaning the floor .
The black residues on the side of the table probably is some reaction between |
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Wed Jun 21 20:25:05 2023, Cao, Infrastructure, VAC, Vacuum chamber bake attempt 1 6x
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TL;DR:
We are not yet able to bake the chamber at 150 deg C due to some current limit, most likely caused power supply switching off. Also,
smoke was observed at some insulation points, mainly in the small arm sections, This is likely because the insulation does not fit well and the velcro
came into direct contact with heat tape. Some Velcro (made from Nylon/ Polyester) has lower melting temperature point (in 90-120 deg C range)
Full |
 Tue Jun 27 21:47:56 2023, Jon, Infrastructure, VAC, Vacuum chamber bake attempt 1
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The electrical overload problem encountered in ELOG 130 has been resolved. The two heater controllers,
which draw up to 14.1 A each, overloaded the UPS and tripped one of its circuit breakers, shutting off power to both power strips mounted above the optical
table. |
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Fri May 12 20:28:34 2023, Aiden, Cao, Physics, VAC, Vacuum chamber Helium leak test
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[Aiden, Cao]
1. Helium leak test
2:00 pm: Uninstall regulator from nitrogen gas tank and move to helium gas tank. Place helium onto
cart and move to the rear door of the clean tent. With the tank remaining outside, feed hose through the flexible wall to use in clean tent - See attached |
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Thu Oct 12 12:11:10 2023, Aiden, Update, VAC, Vacuum chamber Helium leak test
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[Aiden, Tyler, Peter, Jon]
Continued tightening bolts on the turbo pump and 6"-8" reducer to reduce the leak. The final leak test values for the
turbo pump flange was 3.0 e-9 and the other 6"-8" reducer flange was 4.0 e-9.
We will continue to let it pump down as the screws could not
be tightened anymore. Looks like new gaskets will be needed to reduce the leaking on these flanges.
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Fri May 31 19:37:47 2024, Luke, Update, , Vacuum chamber Disassembly
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[Luke, Aiden, Jon, Michel, Tyler]
Work done:
On Tuesday (5/28) we removed the RGA line with minimal difficulty. On Wednesday (5/29) we removed the turbo
pump, which had a few bolts that we needed to cut. We borrowed a dremel with ceramic blades from the machine shop to help remove some of the bolts. On
Thursday we moved the vacuum chamber onto the floor to check and resecure the heating band on the bottom of the vacuum chamber. We then relocated the posts |
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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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Thu Jun 29 18:27:26 2023, Jon, Cao, Infrastructure, VAC, Vacuum bake attempt 3: success!
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[Jon, Cao]
Summary : We resolved problems with heaters tripping power and were able to proceed with chamber baking
1. Circuit connection adjustment
After yesterday elog 137, today we resolved
most of these issues. After Jon contacted Facilities, the LP3B 6 circuit was reset and the cleanroom filter & light panels resumed to work as normal.
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Fri Oct 27 15:16:31 2023, Aiden, Update, VAC, Vacuum Leak Test
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Leak tested the worst flanges on the chamber after moving it and after bake 6. The 6 inch flange connected to the 8 inch reducing nipple is now leaking
at 1.5 e-9, previously at 4 e-9. The 8 inch flange connected to the turbo pump is now leaking at 1.9 e-9, previously at 3 e-9. This means that the baking
most likely improved the seals on these flanges and a hotter bake might fix the leaks for good. |
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Mon Oct 30 08:42:22 2023, Jon, Update, VAC, Vacuum Leak Test
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By 5:30 pm Friday, the pressure had reached 8.6e-8 torr and was continuing to fall. So it seems we are OK to proceed with permanentizing this configuration
(cable routing, heater tape reinstallation).
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Fri Jan 27 18:44:31 2023, Julian , Update, General, Vacuum Chanmber Cleaning
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I used the IPA wipes to wipe down the inside of the chamber the best I could. I cleaned the main chamber but not any of the connecting joints. When I finished
I did a once over with a fresh wipe and found no residue. |
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Mon Jun 3 09:24:48 2024, Aiden, Update, VAC, Vacuum Chamber Rendering
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Here is a new render of the vacuum chamber that includes the 2.75 tee to place the Argon leak right next to the RGA. The conical reducer under the spherical
cube was also replaced with a 4.5 blank. The height from the bottom of the blank to the bottom face of the chamber is 5.45". With the chamber now on 1"
standoffs, we will need a support with a height of 6.45". |
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Fri Dec 15 14:03:02 2023, Aiden, HowTo, VAC, Vacuum Chamber Opening
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[Aiden]
1. Turn off the RGA filament and disconnect it.
2. Record the pressure and then close the angle valve and gate valve on the RGA line
to isolate it from the system.
3. Turn off the backing and turbo pump and let the turbo pump spin to a stop by slowly leaking the chamber. The slower
the safer.
4.Slowly open the vents on the chamber and the turbo pump. Making sure not to raise the pressure too fast.
5. Once done venting |
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Fri Mar 15 16:58:55 2024, Aiden, Update, VAC, Vacuum Chamber Frosti Testing
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[Luke, Luis, Aiden]
On Thursday, March 14 - Took preliminary RGA scans of the empty chamber to compare later on. Vented the chamber and placed the FROSTI
into the chamber. Plugged in the DB-25 connectors into the feed through port and checked the connection to make sure there were no shorts before closing
the chamber and starting the pumps again.
On Friday, March 15 - The pressure in the chamber has come down to 7 e-6 torr. It seems to be coming down |
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Sat Feb 11 00:17:27 2023, Julian, Update, General, Vacuum Chamber Cleaning
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Today I finished wiping down the rest of the vacuum chamber, specifically focusing on the connecting ports and outside surface of the chamber. When I was
finished, I test wiped every surface of the chamber and took pictures confirming the current state of cleanliness; Attachment 1 "Wipes for top and bottom
of chamber's upper lip." Attachment 2 " Top and bottom of chamber's lower lip." Attachment 3 "Inside and Outside main chamber." Attachment 4 "Inside connecting |
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Thu Feb 23 21:12:33 2023, Julian, Update, General, Vacuum Chamber Cleaning
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Today I was able to come in and wipe down both sides of the vacuum chamber lid using the regular alcohol wipes and also wipes that were left to dry in the
fume hood then saturated with acetone. I managed to get a good amount of the residue off both the inside and outside surfaces of the lid, then did a test
wipe of both sides using acetone-soaked wipes; pictures of the wipes are attached below. Once I finished with the lid, I used another acetone wipe to test |
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Mon Feb 27 17:09:04 2023, Pamella , Update, General, Vacuum Chamber Cleaning
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Pamella and Julian finished cleaning the interior of the chamber, chamber lid, and the table. We found some black residue on the side of the table but not
sure what the issue is. A picture of the specific area of the table that is giving off the black residue is attached below. The next step from here would
be to flip the chamber on its side and finish the cleaning the exterior. |
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Wed Jul 5 15:46:47 2023, Aiden, Cao, Infrastructure, VAC, Vacuum Chamber Baking Update
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Cao and Aiden put the RGA back on to the chamber and measured the outgassing rate after the chamber has cooled down from its first bake. The figure
attached shows the RGA measurements with the Argon leak open.
Also put the Full Range Gauge #2 [RGA line] back onto the system to measure the pressure and got a reading of 2.78 E-7 Torr. We believe it |
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Thu Jul 6 16:16:03 2023, Aiden, Summary, VAC, Vacuum Chamber Baking Update
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Pressure Measured Before Removing Gauge 2.31 E-7 Torr.
Went in and turned on the heating tape in increments of 30 degC until 120 degC was
reached. I will let it equilibrate over night and then asses whether or not the chamber can be raised to 150 degC without having the flange to the turbo
pump reach over 120 degC as it is not recommended for that flange to be any hotter.
If it can safely be raised to 150 degC, then only 2 days |
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Thu Jul 20 18:03:19 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Took another set of RGA data after the second bake has cooled down to 27 degC.
Just by visual comparison to the other graphs, the HC levels
of the chamber has gone down further. I will soon overlay the data for an easier comparison.
I also reinstalled the full range gauge above
the RGA line. It is still adjusting itself downwards so I will have to check again to get an accurate measurement of the pressure.
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Fri Jul 28 13:46:17 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Took some more data to look at the HC count. Initial data was from leaving the Argon leak closed and then left it open for 15 minutes and then took
data for the open scenario. Attached are the graphs for these where attachment 1 is the closed scenario and attachment 2 is the open scenario.
From
these graphs it looks like the signal-noise ratio of our calibration line is poor with the ratio between these two being 1.3. This means that the calibrated |
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Tue Aug 1 12:10:03 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Dr. Richardson and I took off the insulation on the lid again to add more insulation in-between the heater tape folds in addition to what was added
on top of the tape after discovering discoloration. Also cleaned the lid with IPA wipes.
Also took more RGA data, one with the leak closed
and one with the leak open. The graphs below this show that the SNR is improving with the ratio now looking to be around 3. The chamber is still too dirty |
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Mon Aug 21 17:13:25 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Came in to take RGA data and found the turbo pump drawing .38 Amps. This was much higher than what it was on Friday. I investigated and found that
the breaker had flipped controlling the power strip that the scroll pump was on. The scroll pump was thus not running. I flipped the breaker back and turned
the scroll pump back on. I do not know if this will be a reoccurring problem as this has happened before, or if this was due to the storm. Either way the |
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Mon Aug 28 14:43:50 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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The PID controllers were turned off on Friday and the chamber was left to cool over the weekend. Just took data and it looks like signal to noise ratio
is pretty bad again. I do not know if this means we need a hotter bake or if the chamber needs some more time to cool down. I will overlay this data and
make sure to take a second set a bit later to compare. Some good news though is that the chamber has reached a pressure below 10e-8 torr with the full |
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Tue Aug 29 19:09:21 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Here are some more plots with the RGA data take August 29. It seems that more pumping time has led to the HC levels being dramatically reduced compared
to only a day ago. The pressure also rises significantly when turning on the RGA filament and it doe not go back down to the pressure before turning it
on while the RGA is still running. The pressure after I left was 6.86 e-8 torr. |
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Thu Aug 31 12:56:29 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Took some more RGA data to see if the HC levels have further declined since bake 4 and it seems that it has started to plateau with August 29 160.7 e-10
Torrl/s and August 31 giving 158.4 e-10 Torrl/s. The pressure of the chamber before taking data was 5.1 e-8 Torr. I have attached an overlay of the data
from August 29 and August 31. It seems that the extra two days has not noticeably changed the data and another bake will most likely be needed to meet |
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Fri Sep 15 17:33:35 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Took some more RGA data and see that the chamber has gotten much cleaner since monday. Next step would be another bake with some focus around heating the
RGA filament more. The pressure in the chamber before testing was 5.32 e-8 torr. |
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Thu Oct 19 11:41:04 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update 6x
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[Aiden, Tyler, Mohak]
Took some RGA data when we came into the room. The pressure of the chamber was 8.63e-8 Torr before turning on the RGA filament.
We saw the usual spike in pressure when the filament was initially turned on. Took some data and saw that the chamber was definitely dirtier since the
vacuum upgrade. See figures below.
Put the heater tape back onto the section that was removed. We may need to rearrange the heater tape again |
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Thu Oct 26 13:00:45 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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Bake 6 was turned off on Monday. Tooke RGA data today and have posted the data below. The pressure of the chamber after taking data was 3.22 e-8 Torr. The
chamber HC levels are still not low enough but I feel with more pumping it will go down as the RGA scan was still slowly going down during the data taking. |
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Thu Nov 9 13:48:47 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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After bake 7 was stopped on Wednesday morning (11,8,2023), I took RGA data of the chamber to compare to a later scan that will be done on Monday to make
sure the chamber has reached its lowest pressure. Below are the graphs. |
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Wed Nov 15 21:52:33 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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| Took RGA data before running the degas mode. Made sure to close off the main volume before running the degas. And left the filament on. |
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Mon Dec 4 11:19:50 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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[Aiden]
Took some RGA data of the chamber after it has been cooling down. I do not believe that this data accurately shows the HC levels in the chamber
as the pressure is still above where it was at before the bake and was still falling. I believe more time is needed to let the pressure fall and for the
RGA filament to remain on to return to a point where the data can be trusted. |
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Thu Dec 7 12:42:42 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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After leaving the RGA on for a few days the chamber has settled at 2.01 e-8 torr. I also have good news that the chamber looks to be even cleaner as the
HC levels are now the lowest they have been being at 26 e-10 Torr l/s. |
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Tue Dec 19 15:45:05 2023, Aiden, Update, VAC, Vacuum Chamber Baking Update
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| Took RGA data for the macor parts inside of the chamber. With the Ar open the HC levels read 30 torrl/s which is around where it was before the bake. |
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Mon Feb 26 15:15:39 2024, Aiden, Update, General, Vacuum Chamber Baking Update
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| Started Bake 12 on Wednesday Feb. 21 and turned the bake off on Saturday Feb. 24. This was a normal low temp bake with the PID controllers set to 110 degC. |
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Sun Dec 17 19:43:18 2023, Aiden, Update, VAC, Vac Heating Update
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[Aiden]
I measured the temperature of the flanges where some of the electronics will go and I found that the RGA flange was at 55C and the two full
range gauges were at 65C. I also stopped bake 9 to cool down for measurement. |
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Mon Oct 23 07:28:57 2023, Peter, Update, VLC Update, VLC Mode Matching
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| I have attached a pdf with slides of my latest updates. |
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Mon Nov 6 11:31:25 2023, Peter, Update, VLC Update, VLC Mode Matching
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| See Update Attached |
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Mon Nov 13 06:15:45 2023, Peter, Update, VLC Update, VLC Mode Matching
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| Weekly Updates Attached in pdf |
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Thu Sep 7 19:24:25 2023, Peter, Update, VLC Update, VLC Launch Chain
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The launch optics up to the Faraday Isolator have been added to the breadboard. In the first image, the optics are (from L to R) the stirring mirror, half-wave
plate, polarizing cube, 100mm f lens, electro-optical modulator, Faraday isolator, 50mm lens (not part of final design), stirring mirror (not part of final
design) |
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Mon Oct 9 11:06:17 2023, Peter, Update, VLC Update, VLC Launch Chain
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Implemented the new stage for the EOM. Took power data at different positions in the launch chain. Beam waist: 0.066mm (beam waist is inside EOM). Power
before EOM: 0.473mW. Power after EOM: 0.452mW. Power after Faraday Isolator: 0.415mW. Might need to adjust better to configure for clipping losses. Images
of setup are attached below. |
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Tue Jan 16 10:01:21 2024, Peter, Update, VLC Update, VLC Faraday Isolator and Mode Matching
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| Attached is a PDF of my weekly updates. |
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Fri Dec 8 11:15:21 2023, Peter, Update, VLC Update, VLC Assembly
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The optics of the visible light cavity have been assembled. The mode matching telescope is folded through the two stirring mirrors at the corners shown
in the image below, with the first lens (f=0.2m) before the first stirring mirror, and the second lens (f=0.5m) between the two stirring mirrors. The distance
from the cavity to the edge of the table is 14cm. There is still some work to be done on the alignment of the cavity, as the beam does not seem to be completely |
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Mon Apr 15 11:51:03 2024, Peter, Update, VLC Update, VLC
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| An update on the VLC project is attached below: |
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Mon May 13 14:53:29 2024, Peter, Update, VLC Update, VLC
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| VLC Update WEEK 7 attached below |