 Mon Sep 21 09:51:57 2020, JM, CARME Status 
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Cooling of baking volume finished over the weekend, attached are some plots of the bakeout test. Bakeout2.png is the thermocouple profile for the entire
period over the week. The heating in the first seven hours followed a nice linear rise of ~5C/hour, in the 7-40 hour period the heating rate slowed due
to an issue with our octagon average limiting the increase in the temperature. The period from 40-65 hours was due to the picologger heating up to unacceptbly |
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Wed Sep 23 13:34:04 2020, JM, Tuesday 22 September
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Turbo-pump Issue approximately 13:00 22/9/20.
While moving the baking octagon into position, the power connector became disconnected from the turbo pump. The pump controller provided the
warnings of connector failure and high pump load (probably due to it reading the frequency of the pump as 0 Hz when disconnected and thinking this was |
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Fri Sep 25 12:58:33 2020, JM, Friday 25/09/20
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10:00 Vessel P = 3.99e-8 mbar, RGA P = 1.4e-6 mbar
10:54 Vessel P = 3.89e-8 mbar, RGA P = 1.4e-6 mbar
Vessel continues to pump down. Baking Jacket fully installed and testing of baking begins before leaving on automatic mode for the week. Some |
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Mon Sep 28 13:04:27 2020, JM, Baking
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I have (fingers crossed) got the baking stepping up nicely now. I have used some of the outer shell to act as a shield and to direct airflow towards
the front and back of the baking volume. I also moved the RE-72 thermocouples to a higher temperature region and replaced the broken thermocouples. The
program is on automatic mode and has currently stepped up to 40C with the max diff reduced to ~4C. |
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Mon Oct 12 10:49:36 2020, JM, First Bakeout of CARME with pumps (cont)
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12 October
10:00 Bakeout temperatures stable. Pressure on the backing line is 3e-7mbar which is the lowest we have achieved on the backing line so far.
Vessel pressure can't be measured at the moment as temperature exceeds the max operational temperature of 80C. |
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Mon Oct 19 13:57:52 2020, JM, Neg Activation
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Neg and Neg-Ion pumps have been connected up to the control modules. Controller on the right is connected to the D-2000s. Middle controller is connected
to the wall section negs (1x2negs in series and 1x3negs in series) and the moving detector negs (2x2 negs in series). Left controller is connected
to the intermediate section negs (2x2 negs in series). Must connect IN/OUT interface on the back of the controller or the alarm for an open circuit is |
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Tue Nov 10 12:25:29 2020, JM, Cable harnesses
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The length of the wire needed was estimated with the aid of a scale image of the detectors in the CARME chamber and foam model pieces. Wire length estimated
by simply cutting wire so that it 'fits' the scale model and by taking coordinates of the end points of the longest sections of wire needed on
the model and calculating a bezier curve to estimate wire length. Bezier curve calculated by inputting the endpoints of the wire and control points such |
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Tue Nov 24 12:24:01 2020, JM, RGA scans
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RGA laptop passcode: tw%11&STA-
RGA scans set up and plotting data as of 11:44
RGA is set to the multiplier mode (4.44e-8mbar) with an accuracy setting of 8, these are for the most sensitive scans. RGA is set to scan masses |
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Mon Dec 7 14:29:12 2020, JM, CARME packing up
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Sat Oct 23 12:58:11 2021, JM, GSI vacuum and bakeout testing summary
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Attachment 1 shows the pump-down of the CARME chamber at GSI before installation of kapton cabling inside the chamber and mounting of the chamber on
the ring. Discontinuity in the plot is from switching between the pirani gauge and IE514 gauge. The pumping of the chamber in the turbo regime follows
the power law where P ~ 1/(nt) due to outgassing from the chamber being dominated by water outgassing which has an n ~1 dependence (for first order |
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Sat Jan 15 11:28:10 2022, JM, Inventory
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Vaccum
DN250CF 1x gaskets
DN200CF 5x gaskets
DN160CF 1x gaskets, 2x blank flanges
DN100CF 69x gaskets, 19x blank flanges, 14
double feedthroughs (1 damaged)
DN63CF 3x gaskets, 2x blank flanges
DN300CF 5x gaskets
DN350CF 0x gaskets
1X WIRE SEAL
DN35CF 3x gaskets, 13 |
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Tue Feb 15 21:28:14 2022, JM, Noisy Channels
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All fees and asics checked to find noisy channels. Channels are listed along with the noise peak height for the low energy plot at 22:00. Run started
~17:45.
Attachment 1 shows 3*L for aida01 with x axis zoomed in on noise peak. Attachment 2 shows stat for aida01-04 in log scale. |
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Wed Feb 16 21:27:31 2022, JM, Cryring signals, Pulser tests, Waveforms 11x
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On 15/2/22 it was noted that the leakage current increases when the motors are moved IN. This is contary to tests conducted on 12/2/22 (elog 192) where
no increase was observed.
16/2/22: Servo motor and pneumatic used to move in by different differences with leakage current observed to increase linearly with distance |
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Wed Feb 16 21:41:11 2022, JM, Run 43 Alpha Background 8x
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22:41
Check Leakage current: (see attachment 1) = 10.01 uA and falling
Check NewMerger tab: (see attachment 2) |
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Mon Apr 24 21:24:26 2023, JM, Preparation for CARME dismount
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CARME currently in vacuum, pressure ~3E-10 mbar. Chamber to be vented tomorrow afternoon by vacuum division. We have active both pirani and hot cathode
gauge to aid.
Equipment removed from the chamber in preparation for dismount of CARME from the ring this week. Equipment removed includes: |
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Tue Apr 25 13:22:19 2023, JM, CARME venting
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CARME venting using nitrogen gas bottle.
Coolant pipes dismounted from the chamber
Feed-through flange for n+n bias flange for bottom detector has a bent pin image attached. Clearer image of bent pin for ERNI connector used |
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Tue Jul 4 17:08:08 2023, JM, Leak test and venting
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This morning the pressure achieved was 1.44E-7 mbar. Leak testing showed an overall leak rate of 1.5E-10 mbar l/s, this is below the previous leak rate
but still significantly above the leak rate from elog 141 of the CARME chamber on its own. Spraying helium, a leak is visible on the VAT gate valve on
the interaction chamber (inside of the ring). The leak rate increases to ~2.3E-10 mbar l/s. No increase in the leak rate was observed elsewhere on CARME |
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Wed Jul 5 19:27:13 2023, JM, Pump down and leak test
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CARME and the interaction chamber have been pumping for ~26 hours, P=4.15e-7 mbar, attached figures show the current pump down plot in comparison to
the two previous pumpdowns in the last 2 weeks and the pump down with the bare chamber in 2020. The gradient of the pressure reduction appears to be improving
for each pump down, either due to conditioning of the chamber or the reduction in leaks. |
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Thu Jul 6 15:26:39 2023, JM, Leak update
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The leak on the actuator arm bellows has been attempted to be sealed using UHV vacuum seal spray. The spray had the opposite to the desired effect and
the leak rate increased. When spraying with helium the leak rate had increased to 1e-9 mbar l/s. After lunch a second application of the vacuum seal spray
was attempted, however the leak was not sealed. The base leak rate had also increased to the 1e-10 level up from in the morning and yesterday. With the |
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Thu Aug 10 07:51:43 2023, JM, Baking tent and heater testing 8x
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09/08/23
Attached is the current pumpdown plot taken from grafana.
I have started to re-work the baking tent in order to close gaps from its initial installation. The heaters work and were tested to a temperature |