08:52 Overnight the DAQ was left running to check if there was any individual radioactivity in the Si.
      This is stored in R7_75

      It was observed that even with no beam the detectors continued to increase in leakage current overnight but slowly - Attachment 1
      We then stopped the DAQ and gave the detector a single shake.
      This caused the leakage currents to decrease but not to the same level that they did last night - Attachment 2

13:45 Bias tripped as people removed the cover on the windows on the interaction chamber
      Iset was still at 11uA for safety
      Will leave off until they are finished

      

09.30 CARME chamber status

      Edwards scroll pump ON
      Edwards Speedivac valves #1 & #2 OPEN
      VAT gate valves OPEN

      Re-connect Leybold Pirani gauge to local display/control
      CARME chamber pressure 2.4mbar

      Scroll pump should be able to achieve < 0.1mbar - indicates significant leak

      Davide will first check bolt torques for all flanges opened during most recent vacuum cycle

12.05 Additional torque did not resolve problems
      ML test COF600 seal with isopropanol and observed increased chamber pressure

      Will open COF600 seal after lunch

13.55 COF600 seal removed - one section marked by Kapton tape shows some distortion and a burr on the inner diameter - see attachments 1 & 2. 


      ML speculated that perhaps the seal was lightly too long and a section of circumference was forced outwards?
      Vacuum surfaces cleaned with isopropanol and tissues - red/brown discoloration probably indicating copper observed

14.30 New COF600 seal installed, flanges closed, bolts finger tight, bolts then systematically torqued in small increments 

      COF600 torques finger tight, 10, 20, 30, 40, 60, 80, 100, 120, 140, 160Nm x2
      DN100 flanges doenstream finger tight, 8, 16, 24Nm

16.40 Start scroll pump and slowly rough chamber

18.00 Roughing CARME chamber pressure flatlines c. 30mbar indicating a large leak.
      ML ran some isopropanol around COF600 flange and observed response in roughing pressure of c. 0.2-0.3mbar at c. 30mbar which appears to confirm COF600 is leaking.


      

17.33 IE514 pressure 6.4e-11 mbar, ambient temperature +20.8 deg C

      The thermocouples on the 3x groups of heater elements have been detached from direct contact with the heating element and now float abpove the heating element by 2-
3cm - see attachments 1 & 2

      The vacuum group IE514 and Ametek RGA are still attached to CARME - see attachment 3. Have requested vacuum group remove them.

      The 'air side' of the Be window on the interaction chamber is under vacuum provided by small Agilent scroll pump.

      

Login to nnrpi1 from carme-gsi using ssh

Execute the caen_screen.sh script

pi@nnrpi1:~ $ cat ./caen_screen.sh
if ! screen -list | grep -q "caenhv"; then
	screen -f -S caenhv /dev/ttyACM0 9600
else
	screen -x caenhv
fi
pi@nnrpi1:~ $ ./caen_screen.sh

Enter the text string 'caen'

If the CAEN display program is already running you will only see page updates/changes.
- enter q ( quit ) and then d ( display ) to re-display the entire screen.

See attachment 1

1. ssh into lxpool network: ssh <user>@lxpool.gsi.de
2. ssh into atppc022.gsi.de: ssh carme@atppc022.gsi.de (This is an rpi access server. Don't run code)
3. ssh into carme server: ssh npg@carme-gsi

For the password to the carme user account on the cryring network please contact O. Hall or J. Marsh.

08:00 Woke up to message from Carlo explaining the server had crashed.
      Anydesked into the machine.
      Merger was showing just data transfer it was not showing Transfer => Merger

      Went through the steps detailed in https://elog.ph.ed.ac.uk/DESPEC/36 to recover it.
      After following these steps was again able to forward data from the merger.
      Tested and it now sends on data again.

      Setup the screen session for the caen bias and restarted the logger program.
      Restarted the gnuplot script to plot leakage current
      Started the online monitoring software and browser.

      Have posted in the chat that the DAQ is now running again.

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 2, 12, 16, 18, 28, 32, 40 and 44 in the range 1e-9 to 1e-14mbar. Mass2=7.85e-11mbar,  Mass12=1.45e-12mbar,  Mass16=1.41e-11mbar,  Mass18=4.78e-10mbar,  Mass28=1.53e-11mbar,  Mass32=3.46e-12mbar,  Mass40 = 1e-14mbar,  Mass44= 3e-13mbar. Slight variability in each measurement is ver small for higher pressures and larger for lower pressures (see image attached). 

Plan is to switch each ion pump off individually and observe the effect on the RGA scans. Once off I will leave for 30 mins to see if any difference can be seen. Afterwards I will switch of 2 pumps then 4 pumps at a time. 

12:06 Ion pump 1 (furthest left pump=1, furthest right=4) turned off, no immediate change in RGA.

12:38 No change in RGA, turning pump 1 on again and switching off pump 2. Pump 1 took ~15s to stabilise back to a pressure of <8.9e-12mbar once turned on again. 

13:08 No change in RGA, turning pump 2 on again and switching off pump 3. Pump 2 took ~15s to stabilise back to a pressure of <8.9e-12mbar.  

13:38 No change  in RGA, turning pump 3 on again and switching off pump 4. Pump 2 took ~15s to stabilise back to a pressure of <8.9e-12mbar.  

14:08 No change in RGA, all pumps back ON. RGA has not changed since pumps wer switched off and on, pressure on the hot cathode gauge has risen slightly however I think this is due to the day/night cycle of the pressure. 

14:12 All 4 ion pumps turned off

15:12 No observable change in the RGA

15:33 Ion pumps all back ON. No change in RGA

15.45 Start data file G22-201/R66 
      Beam/target overlap test

06:45 New data file G22-201/R57

      Right arm at 64.60 mm

      Left arm IN at 36.54 mm

      horizontal beam position 8.75 mm

      vertical beam position -5mm
   
      Changed electron cooler set point to 244.4 V

      Read value 243.851 V

      Collector current 4.31A


      DSSSD bias & leakage current OK - attachment 1

      FEE64 temperatures OK - attachment 2

      ADC data item stats - attachment 3

      per FEE64 Rate spectra - attachment 4
      
      Beam intensity - ~ 5.7E7 pps

      Target density - 2.91E11 atoms/cm2

8:35


      DSSSD bias & leakage current OK - attachment 5

      FEE64 temperatures OK - attachment 6

      ADC data item stats - attachment 7

      per FEE64 Rate spectra - attachment 8
      
      Beam intensity - ~ 4.8E7 pps

      Target density - 2.86E11 atoms/cm2
      
      There is no beam since 8:26 and Gleb is informed. 08:46: Beam is back.

10:49


      DSSSD bias & leakage current OK - attachment 9

      FEE64 temperatures OK - attachment 10

      ADC data item stats - attachment 11

      per FEE64 Rate spectra - attachment 12
      
      Beam intensity - ~ 4.0E7 pps

      Target density - 3.66E11 atoms/cm2


13:18


      DSSSD bias & leakage current OK - attachment 13

      FEE64 temperatures OK - attachment 14

      ADC data item stats - attachment 15

      per FEE64 Rate spectra - attachment 16
      
      Beam intensity - ~ 5.0E7 pps

      Target density - 5.67E11 atoms/cm2
      



     

15.40 DSSSD bias & leakage current OK - attachments 1-2
       log shows variations due to ambient temperature changes in CRYRING hall

      FEE64 temperatures OK - attachment 3

      WR timestamps OK - attachment 4

      System wide checks Ok *except* global clock (aida16) - attachments 5-6

      ADC data item stats OK - attachment 7

      per FEE64 Rate spectra - attachment 8

      per FEE64 1.8.L spectra - attachments 9-10
       have not been cleared in some time probably - will zero histograms & stats for later review

     per FEE64 1.8.W spectra - 20us FSR - attachments 11-12

     Merger, TapeServer etc - attachments 13-14
      data file G22-222/R51_15

     Motion control - attachment 15

16.01 all histograms & stats zero'd

16.43 online per DSSSD energy spectra - attachment 16

      photographs of CRYRING beam & target diagnostics - attachments 17-22

18.45 Left DSSSDs cycled to clear high rates (c. 250k/FEE64) aida01-aida04 per https://elog.ph.ed.ac.uk/CARME/603

18.49 DAQ continues data file G22-201/R51_27

      DSSSD bias & leakage current OK - attachment 23

      FEE64 temperatures OK - attachment 24

      ADC data item stats OK - attachment 25

      per FEE64 Rate spectra - attachment 26

      online per DSSSD energy spectra - attachment 27

19.00 Beam less stable but most cycles 5e+7 or higher
      Target peaking c. 1e12 dropping to c. 6e11

19.09 CRYRING hall temperature increasing, DSSSD leakage current increasing - attachments 28-29


20.06 Beam less stable most cycles 1-2e+7 or higher
      Target c. 1-2e12

20.15 JM/CB advise changing Lakeshore 336 Temp Controller set point from 29k to 29.5K - done
      Average pressure decreases but rapid variations still observed - see attachment 30


21.00 contacted HKR to improve beam stability - they were alreday working on it but did not know what was causing the problem - will contact on-call CRYRING expert

      cycled L DSSSD to reset rates
      
21,10 beam 0ff - DSSDs OUT

      Increased target temperature to 30K to solve instability that developed again up to E12 density range.


      


 

Doing afternoon check. Checked the leakage currents, all ok. Attachment 1

Temperatures ok, attchment 2

System wide check, all correct.

Statistics ok (as far as we can tell) attachment 3

Spectrum browser ok, attachment 4

Checked merger, spinner spinning...

Beam current is around 2.2 E7 and the target dencity is 6.3E11 cm2.

A pump cart and leak cart have been connected to the chamber via the top turbo at the back of the chamber. An air line has also been connected to the valve to open/close it. The pirani gaige has also been replaced by a blank flange, a gauge on the pump cart can measure the pressure in its range. The turbo fan and controller were set up and pumping was started after lunch. 

While pumping, the hot cathode gauge was connected to its controller and bakeable shell installed. Gauge will be turned on if pressure is sufficiently low tomorrow, currently no gauges are 'active' on the chamber with the only gauges on the pump cart. 

An RGA is attached to the pump cart and can be seen in attached photos. Majority of contribution in RGA is water with significant contributions from gases in air (nitrogen, oxygen etc) as expected during early pumping. RGA is also quite noisy. 

The leak rate observed is below the minimum value the leak cart can detect (<1e-12 mbar*l/s). Helium was sprayed around the chamber and on the wire seals, however no change in the leak rate was observed, so no significant leaks!

The turbo has been left to pump overnight with the pressure 2e-5 mbar at 16:15. Attached is the pressure against time from 15:00 till 16:15, the rate of pumping in this period was 0.68e-5 mbar/hour. 

09.15 Following overnight pumping of CARME chamber by Leybold turbo
      Pirani 1.00e-3 mbar IE514 2.83e-7 mbar

     The Leybold IE514 gauge currently in use is the CARME unit ( serial # 1054 ). The calibration data can be found at https://elog.ph.ed.ac.uk/CARME/56


09.44 Pirani 1.00e-3 mbar IE514 2.71e-7 mbar

10.10 Leak tester attached to backing line

      Valves to leak tester and turbo (connection to Edwards scroll pump in between) closed.

      Stop Edwards scroll pump with magnetic valve 'red' button - magnetic valves closes and Edwards scroll pump is switched off.

      Open valves to leak tester and then (slowly) turbo.

      Wait for leak tester to settle in e-12 mbar.l/s range. Leak tester pressure 3.6e-3 mbar. IE514 2.69e-7 mbar.

11.00 Pirani 1.00e-3 mbar IE514 2.42e-7 mbar
      Leak tester 1.8e-10 mbar.l/s

13.04 Pirani 1.00e-3 mbar IE514 2.06e-7 mbar

      Leak testing.
      Downstream DN100 flanges from CARME to dipole OK
      Lower NEG power connector feedhtrough (downstream chamber) OK
      Left hand side (looking downstream) bellows OK

      c. few e-9 mbar.l/s leak bottom left (lookimg downstream) of COF600 wire seal

      Additional torque to M16 bolts bottom left - c. 10 bolts -> 220Nm+

      c. 0.1-0.3e-11 mbar.l/s

      Further checks around circumference of COF600 seal reveal some small leaks c. e-11-12 mbar.l/s.? However background rate
      in leak tester too high for sensitive test - will await recovery to resume checking.

14.00 Pirani 9.8e-4 mbar IE514 1.96e-7 mbar
      Leak tester 4.9e-10 mbar.l/s


14.35 DSSSD test
      IE514 OFF

Ambient temperature 21.5 deg C

Top right
-10V -4uA
-20V 10uA
c. -30V > -20uA trip

Top left
-150V -5.15uA

Bottom left
-150V -4.97uA

Bottom right
-150V -6.33uA

Top right (repeat)
-20V -10uA
-25V -14uA

15.28 IE514 ON
      Pirani 9.8e-4 mbar IE514 1.87e-7 mbar

15.40 c. few e-9 mbar.l/s leak around magnetic valve - probably not an issue in terms of backing performance but may interfere with/confuse leak testing

16.05 Pirani 9.8e-4 mbar IE514 1.74e-7 mbar
      Leak tester 1.2e-9 mbar.l/s

Will leave CARME pumping with leak tester on roughing line and see whether leak rate recovers. If so, will continue leak tests tomorrow. 

18.50 Pirani 1.00e-3 mbar IE514 1.48e-7 mbar
      Leak tester < 1e-12 mbar.l/s (leak tester valved off)

23/06/23

Pumpdown started with the scroll pump 17:15 . The turbo-pump was started 17:55. Gate valve was closed and the turbo turned of at 19:20 due to no working fan on the turbo. 

24/06/23

Ion gauge was activated at 11:56, P= 3.7e-5 mbar. Attached pump-down curves begin from when the ion gauge was activated.

The first plot is a comparison was a calculation for water outgassing in the chamber (which has many assumptions) but is a good guide on the expected 1/t decrease in pressure over time. The second plot is a comparison to previous turbo pump-downs in 2020 and 2021. In 2020 the chamber was bare with no instrumentation. In 2021, kapton and detectors were installed, but the pump down was conducted in several stages. Pressure readings are taken from the gauge reader in the cave, the vac plot viewer online appears to show a slightly different reading. 

 25/06/23

10:30 P= 7.11e-7 mbar. Opened valve on leak cart and saw a large increase in the pressure (above ion gauge level). Closed valve to leak cart, pressure recovered quickly (1.28e-6 mbar after ~ 30 mins). Pressure in the leak cart ~3e-3 mbar. Possibly small trapped volume between valves on the leak cart. Opened valve to leak cart again, no pressure increase observed in the chamber.  

11:40 Leak testing. Base leak rate ~5-6e-10 mbar.l/s.  Spraying helium on the seal between the bottom of the interaction chamber and the newly installed valve saw a large increase to  >1e-8 mbar.l/s. Closer attention suggests the leak may be from the rotatable flange on the bottom of the interaction chamber. An increased leak rate to 1e-9 mbar.l/s was also observed on the diamond window on the inside of the ring. Spraying around wire seal and feed-through flanges on chamber on the inside of the ring gave a leak rate of 6e-10 mbar.l/s. This may be a small leak, but is most likely noise on the leak detector or drifting helium to the large leak on the interaction chamber. Cannot determine prescence of small leaks while the large leaks are active. Closing valve to leak cart saw the leak level drop to <1e-12 mbar.l/s. 

Attached images show sites of the major leaks on the interaction chamber. 

11.40 Pirani 1.00e-3 mbar IE514 2.23e-08mbar

15.15 7d/24h vacuum plots

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.  

CARME and the interaction chamber were leaked tested again today. The base leak rate has reduced significantly from 1.5e-10 mbar l/s to <1e-12 mbar l/s. All flanges on the interaction chamber were tested. A leak is still visible on the gate valve, however the magnitude of the leak has decreased significantly from 2.2e-10 to 2e-11. No other leaks observed on the interaction chamber. 

All flanges on CARME checked again, no leaks observed on flanges or wire seal. Leak was observed on the bellows of the left hand side (inner ring) actuator arm. Leak is not on either the small flange box side or the large flange on the chamber, but on the bellows itself. Image attached. Leak rate is 2e-10 mbar l/s. The actuator was moved with the pneumatic motor once to observed any effects, no effect on leak rate or the chamber pressure.

 Replacing the bellows is very challenging and will likely require removing the detectors installed on the rod. Current plan is to continue with the baking and re-evaluate post bakeout. The bellows will be baked but should not experience the same temperatures as the flanges on the chamber. Future experiments do not require extremely forward angles so that the actuator arm can remain fixed in place to not cause a n increase in the leak, the leak rate can be compensated by the large neg pumping power. 

16:00

Check Fee temperatures: all green (see attachment 1)

Check statistics tab: ADC data items (see attachment 2)

                                 Good events (see attachment 3)

                                  ADC coincidence-info #8 (see attachment 4)

Check NewMerger tab: (see attachment 5)

Check Leakage current: (see attachment 6)

Check the following plots: LowEnergyExTotal (see attachment 7)

                                         LowEnergyEyTotal (see attachment 8)

                                         LowEnergyXYTotalDSSD0 (empty.)

Check Spectrum Browser tab: (see attachment 9)

Check system wide checks tab: all okay.

All is good.

17:00

Pulser walkthrough completed on run R38

290

280

270

250

240

230

220

210

210 / 10

230 / 10 (can't see)

210 / 5 (can't see)

190

90

150

130

70

50

10 (can't see)

30

15 (can't see)

Pulser to 70

17:30 File G22-88/R8

Pulser walkthrough

EGG Ortec 448 Pulser

Amplitide 90,000-10,000 @ 10,000 step
Normalise 5.0
Attenuators x5 IN
t_r 100ns
Tau_d 50us
Frequency Int Osc 50Hz
Polarity + ( - polarity via Cooknell SA1 Sum & Invert Amp )

18:10 Moved to new run R9

Pulser off. Overnight background.

13.41 DAQ start - file G22-88/R4

Pulser walkthrough

EGG Ortec 448 Pulser

Amplitide 90,000-10,000 @ 10,000 step
Normalise 5.0
Attenuators x5 IN
t_r 100ns
Tau_d 50us
Frequency Int Osc 50Hz
Polarity + ( - polarity via Cooknell SA1 Sum & Invert Amp )

File G22-88/R4

14.08 DAQ stop file G22-88/R4_8

R3 started

Pulser ON. Approx 2 kHZ.

1.8*w waveforms attachments 1+2

ADC data items statistics - attchment 3

1.8*L spectra - attachments 4+5

Pulser widths are larger than during testing prior to the Feb beamtime. Widths in Channels;

aida01 = 76

aida02 = 82

aida03 = will upate all later tonight..

R3 ended. Pulser OFF

17:15

R4 Started. Alpha background run.