Following overnight pumping by Leybold turbo pump

09.12 6.26e-8mbar, 2.8e-6mbar (RGA station), leak rate 5e-12 mbar.l/s

09:52 6.08e-8mbar, 2.8e-6mbar (RGA station), leak rate 8e-12 mbar.l/s

10.10 6.02e-8mbar, 2.8e-6mbar (RGA station), leak rate 8.5e-12mbar.l/s 
KM says leak cart currently isolated CARME chamber + RGA cart - no He
has been used around chamber this week so figure represents noise.

10.36 5.94e-8mbar, 2.8e-6mbar (RGA station), leak rate 4.7e-12 mbar.l/s

10.40 KM isolated RGA station (@RGA station) from CARME chamber to replace current RGA (FC sensor) with a more sensitive RGA (with multiplier + FC sensor) 

CARME vacuum pressure (with no backing) will rise somewhat during this process

11.17 1.35e-7mbar

11.20 New RGA install complete, backing line opened, CARME pressure recovers in < 10s to 5.83e-8mbar

14.08 5.59e-8mbar, 2.7e-6mbar (RGA station), leak cart disconnected (by KM)

Cables for neg and neg ion pumps connected with cables trailed out of the octagon through back and front of the octagon. Neg-ion pump connectors are labelled with Kapton 
tape to prevent confusion with neg connectors. Baking jacket has been partially constructed and will be completed tomorrow. 

Detector is not biasing as it has in previous tests. Last bias 15/1/22 see previous elogs, max leakage current ~10 uA at 150V

Detector bias increases well above 10uA for voltages as low as 30-40V. Optical windows covered, Y09 valves closed, large ion pump OFF and both ion gauges OFF produces similar results but with a slightly lower leakage current.

Grounding and pulser cables removed from FEEs and jumper attached to nn bias adaptor card - no change. Bias module swapped out - no effect. NIM rack shows expected voltages (6,12,24) on multimeter.

AIDA03 - disconnected. Behaves as expected. Get waveforms and pulser peak. Pulser peak FWHM ~ 70 channels, noise transients observed.

AIDA02 - Not producing ADC data

AIDA01,04,05,06,07,08 - Very high rates - noisy

FEE mounts for 5,6,7,8 disassembled to access adaptor boards. No sign of debris which could cause short on adaptor boards. 

Adaptor boards removed and checked against spares with multimeter. Both show same characteristics. Pins on feedthrough checked using multimeter. No longer see -18.5 KOhm between bias pins, no see 140 kOhm which is similar to bias pin to non bias pin from prevous tests.

Camera on interaction chamber removed and replaced with foil, no change. 

Ion gauge (Edinburgh group) turned ON

Decided to move detectors using motors. Movement caused change in bias characteristic of the detector. Initial movement was 50 repetitions in and out over which the bias was increased from 10V to 140V. Over this range the detector exhibited diode like behaviour. The difference between the in and position and out position caused a 0.5 uA difference in leakage current. Once stationary, the current was stabel at 140V but after 20s current increased rapidly and tripped.  

Increasing bias again to 30V while stationary (out position on motors) gave 7.3 uA , going to 60V tripped again. 

Moving the detectors IN but keeping stationary gave a stable current at 30V of 4.2 uA increasing to 70V tripped again. Turning off the gauge reduced the current at 30V to 2.9 uA and 70V to be be ~15.5 uA. Opening an optical window at 70V saw no change in leakage current. 

Possibility thermocouple attached to or around the detector may have come loose within the chamber? Thermocouples outisde of chamber removed from thermocouple flange so they don't interact with outside of chamber. 

Detector biased to 60V - 10 uA. Detector position moved in and out 20 repetions, during movement current dropped to 2.85 uA. After motion stopped leakage current remained stable at 2.85 uA. Optical window opened no change. Torch light shone into optical window - increase in leakage current to 3.5 uA. Torch off - return to 2.85 uA. 

Motion started again for 50 repetitions to test stability of leakage current. Current varies between 2.84-2.88 uA during movement, settles to 2.85 uA once motion stopped. 

FEE holder reassembley. Involved turning off bias, unplugging bias cables and rebuilding assembley. FEE holders reaasembled with FEEs reconnected. Water cables, HDMI, ethernet, power connected. Bias turned off and on during reassembley multiple times to check for changes. Each time bias at 60V remained 2.85uA. Each time lower voltages appear to show diode like response in leakage current output. 

Pulser connected and FEEs turned back on. Aida05 appears not producing ADC data rates 8 kHz on statistics page -investigate further. Aida06 rate ~70 kHZ can see pulser. Aida07, 08 nn bias show rates ~300 kHZ possible not enough bias for nn side. Rate for all FEEs yesterday (unbiased) was 200-300 kHZ except for AIDA03 disconnected and AIDA02 which wasn't producing ADC data. Photo of Aida06 spectra attached (log scale for pulser). 

FEEs turned OFF. Bias left on 60V - 2.85 uA see if stable overnight, stable for approx 2.5 hours before leaving cryring. Detector moved to OUT position, pin back in. 

To do - Grounding, reduce noise, waveforms,  investigate AIDA05, how high can we bias?  

To log into appc218 desktop:
same login and password as to carme@atppc022.gsi.de

To start anydesk

1. make sure a monitor is plugged into the carme computer!
2. ssh into npg@carme-gsi
3. su terminal
4. killall anydesk
5. systemctl start anydesk
returns an anydesk backend, service and tray
Anydesk is now accesible 
 

Moved pneumatic motor in and out several revolutions

Biased detector up to 100 V, I ~ 12.4 uA ambient temp c. 21 deg C

Moving detector in increased leakge current to ~14.5 uA, moving detector out dropped leakage current back to ~12.4 uA

aida05 - pulser width 21 chn (slightly lower than yesterday)

aida01 - pulser width 124 chn

aida02 - double peak (is not currently grounded)

aida03 - 183 chn

aida04 - 212 chn

Attachment 1     1.8.L spectra p+n FEE64s

Attachment 2      per FEE64 rate spectra

Attachment 3      aida05 1.8.L, 1.8.W and rate spectra

Attachment 4      FEE64 temperatures - OK

Attachment 5      per FEE64 ADC data event stats - rates for aida01-aida04 significabtly lower than yesterday presumably due to detector bias -100V

Attachments 6 & 7 per FEE64 1.8.W spectra

Attachment 8      1.8.L spectra for n+n FEE64s

regrounded aida02 back to cryring ground - required removing star configuration of all fee grounds and making a new

aida05 - pulser width 30 chn 

aida01 - pulser width 300 chn

aida02 - 220 -> double peak gone 

aida03- 190

aida04 - 200

Perhaps star configuration isn't as tight as before - re tighten star section

Re tightened section -> no impact on pulser widths

Moved detector in using pneumatic -> no impact on pulser widths

Added a grounding cable from the 19 inch rack to the same CRYRING ground that the fees are connected too. Stats around 2-3k, slow comparator = 0x64, bias=100v, I=12.18 uA

aida01  ~ 260

aida02 ~ 177

aida03 ~ 178

aida04 ~ 187

aida05 ~28

Removed CRYRING ground. Fees and rack connected together still. 

no change

Bias supply module is floating

ion pumps off, gauge off -> no change in waveforms, leakage current dropped to 8.7 uA

aida01 ~ 255

aida02 ~ 176

aida05 ~ 26

Removed all vacuum systems and motors power from 19 inch rack power. Connected to the rack are now: NIM bin, network switch, 2 inputs to mains relay, raspberrypi, pi dlink usb connector, VME crack

aida01 ~ 220

aida02 ~ 154

aida05 ~ 27

aida03 ~ 181

aida04 ~ 193

Moved power cable for 19 inch rack to CRYRING 'clean' power source

aida03 ~ 211

aida04 ~ 212

aida01 ~ 317

aida02 ~ 215

aida05 ~ 29

Reconnected CRYRING ground 

aida01 ~ 301

aida02 ~ 203

aida05 ~ 28

aida03 ~ 181

aida04 ~ 191

Current status 17:00:
All CARME vacuum equipment is off (turbo, SIP power modules, NEG power modules, gauges) - roughing pump is on but is valved off from the turbo which is valved off from chamber

Motors and motors pi are off. Detectors are fully out and the pin has been reinserted. 

Bias ON 100V, 8.5 uA. Pulser ON, all equipment connected to 19 inch rack power ON.  Jumper is on link 1 for nn bias adaptor card only. 

measurement 1 -string
intermediate (smaller) chamber - 2144 (mm) circumference,  measured half circumference 1072 mm 
outer (larger) chamber - 2160 (mm) circumference, measured 1/4 circumference 540mm

measurement 2 - foil tape
intermediate (smaller) chamber - 2156 (mm) circumference,  measured half circumference 1078 mm 
outer (larger) chamber - 2172 (mm) circumference, measured 1/4 circumference 543mm

Difference from centre to flat surface on outer chamber is 344 mm on drawing -> say 346 mm radius -> 2174 mm circumference
Part 620FBM600 from pfeiffer intermediate chamber 690mm diameter, 2168mm 

Measurements of parts of CARME frame to the target frame as a reference for target frame position.

Attachments 3+4 show clearance between CARME frame and target frame just below interaction chamber from inside and outside of the ring. Attachment 5 is clearance in same section but above interaction chamber

Attachment 6 - measurement between outer edge of CARME frame and inner edge of target frame - 165mm

Attachment 7 - measurements between outer edge of CARME frame and inner edge of target frame - 455 mm 

Attachment 8 - measurement between lower edge of CARME frame and lower edge of target frame - 1245 mm

Attachment 9 - measurement between top of VAT valve and lower edge of target frame - 233mm (left arrow), 216mm (right arrow)

Waveforms and discriminator ON. Pulser re-connected to all fees via daisy chain. V=100v, I=8.36uA

Pulser peak widths (ch FWHM)

aida01 ~ 109

aida02 ~ 98

aida05 ~ 24

aida03 ~ 118

aida04 ~ 136

Attachments 2, 3 & 4 1.8.W spectra, 20us FSR

Attachment 5 FEE64 temps OK

Attachment 6 per FEE64 ADC data item rates OK

Attachment 7 per FEE64 rate spectra

Merger reset following procedure from https://elog.ph.ed.ac.uk/DESPEC/36. Keywords for future elog search NetVar, xfer links

Pulser walkthrough R94

EG&G Ortec 448 Pulser settings

Amplitudes 90,000 - 10,000 @ 10,000 step

Attenuators x5 IN

t_r 50ns tau_d 50us

polarity + (- polarity via Cooknell SA1)

Frequency int relay

Motors box turned ON, motors pi ON, dlink network connector ON. Motors box, pi and dlink all in 19 inch rack but power supply is from a uk mains extender daisy chained to vacuum mains extender.  19 inch rack power supply remains on clean line.

Pulser peak widths (ch FWHM)

aida01 ~ 105

aida02 ~ 98

aida05 ~ 23

aida03 ~ 132

aida04 ~ 144

See attachments 8 & 9

Detectors moved in by pnuematic only. Leakage current increased to 9.6 uA (same as leakage current during bias ramping)

Pulser Walk R95

Pulser settings as above

See attachments 10 & 11

Detectors moved back out . Motors box, pi and dlink still turned ON. Leakage current to 8.36 uA

Pulser Walk R96

Pulser settings as above

See attachments 1 & 12

Jumper removed from nn bias fee adaptor board (aida04). No jumpers on any adaptor boards now. V=100V, I=8.36uA

See attachments 14 & 15 - 1.8.W spectra 20us FSR

Pulser on 90,000 x5 attenuate

aida01 ~ 123, centroid ~14691

aida02 ~ 106, centroid ~ 15038

aida05 ~ 23, centroid ~ 14414

aida03 ~ 125, centroid ~ 50838

aida04 ~ 127, centroid ~ 51754

Jumper reinstalled on aida04 nn bias. Note only link 1, link2 inaccesible with fee inserted into ERNI. See attachment 13

aida01 ~ 123, centroid ~14688

aida02 ~ 114, centroid ~ 15034

aida05 ~ 23, centroid ~ 14411

aida03 ~ 118, centroid ~ 50854

aida04 ~ 135, centroid ~ 51697

Pulser off. Background run to be left overnight started 14:24 R97. V=100v, I=8.36 uA.

Internal CARME installations complete. 

• New strain reliefs (flange side) installed on each cable harness.
• 2x sets of SAES UHV1400 NEG pumps installed and connected to 2x power feed-through flanges -> continuity checked OK -> 3x UHV1400 modules gives a resistance of 7.4 Ohms, 2x UHV1400 modules gives resistance of 4.8 Ohms. 
• Pins B & D open circuit wrt ground ( DMM OL > 20M ? )
• Pin C connection to ground OK 
• Internal thermocouples connected. Middle thermocouple connected to strain reliefs, right thermocouple connected to a standoff on the detector, left thermocouple floating (see attached images). Resistance on thermocouples checked for middle and right thermocouples ~ 4 Ohms per thermocouple. 

V-I tests performed prior to closing CARME. All detectors show expected curve, but light leaks are present. Pressing my hand against the aluminium shield yielded 0.5-1.5 uA drop in leakage current. Could not turn off lights for the test due to other people working in the cave. Will repeat test when closed. Temperature in the cave ~ 21.5 C. 

Both chamber sections have now been closed. Wire seal appeared correctly positioned immediately prior to final close. Bolts closing the wire seal have been tightend to 100 Nm, plan to increase to 140 Nm tomorrow. DN100 feed-through flanges have been tightend with a torque of 24 Nm. 

Plan is to move chamber back onto the ring tomorrow and get ready for leak testing. 

The wire seal has been tightend further to 160 Nm. Open neg feed-through flange has also been fully tightend. 

The CARME chamber was then slid back onto the aluminium frame on the ring. Two carriages were damaged during the sliding process, which have now been replaced. Carriages were replaced by lifting one end of the upper frame section using the crane by only ~1mm. This was sufficient to slide out the broken carriage and replace it (see images to be uploaded)..  It appears there is some deformation in the rails on the temporary frame as CARME is slid across, which resulted in the damaged carriages -> further refinements are required for future slidings. The height of the chamber has been checked using the laser allignment.  

The turbo pump has also been mounted to the top of the chamber . Current plan is to close to the interaction chamber tomorrow and begin pumping.  

23/06/23

The CARME chamber and interaction chamber were connected and section 9 has been fully closed. New valves have been installed on the interaction chamber, in addition to new diamond windows. A leak cart has been connected to the backing line of CARME. Before begining the pumpdown, the manual valve between the interaction chamber and the electron target was closed. 

The pumpdown was started at 17:15,  the valve on the scroll pump was very slowly opened to not damage the berylium window. By 18:00 a pressure of 1 mbar was achieved and the turbopump was activated. By 18:20 a pressure of 2E-3 mbar was achieved, the ion gauge was activated and briefly flashed 5E-4 mbar but this is over its limit so the gauge shutdown. At 19:20, 1.3E-3 mbar was achieved, the ion gauge was activated but the reading was 1.7E-4 mbar which is still over its limit. The turbo fan was not working and temperatures on the turbo were ~50C and increasing, so it was decided to close the main gate valve and turno off the turbo overnight in order to fix the fan.

A bias test of the detectors was also performed while in vacuum, T=20.5 C. All detectors show expected V-I curve and the leakage current is ~1-2 uA lower than the previous test in air, probably due to reduced light leaks. The top right detector did initially produce >10 uA at 20 V but the adaptor card was not properly seated on the p-n feed-through. Seating the adaptor card correctly yielded the expected V-I curve. Further inspection of the pins on this feed-through will be performed tomorrow.  

24/06/23

Overnight the pressure had increased to 0.8 mbar. Opening the gate valve decreased the pressure by an order of magnitude. The turbo fan was fixed and the turbo was re-activated, the pressure dropped to 1E-3 mbar level within 20 minutes.  Ion gauge was turned on after 30 minutes with a pressure of 3.7e-5 mbar. Pump down plot and comparison to previous pump downs will be uploaded in a seperate elog. Turbo pump maximum temperature reads 46C and has been consistent for several hours. 

V-I tests completed for the right hand side detectors. Leakage currents ~0.4 uA higher than yesterday which is consistent with the increase in temperature of ~ 0.5-0.7C. 

Attached are images showing the messages for normal turbo-pump operation

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. 

The motors were moved using the pneumatic only, in and out for several cycles to gauge the effect on the vacuum. For the left arm no change in pressure was observed. For the right arm a small increase of 0.04e-7 mbar was observed which was quickly reduced by the turbo. 

The detectors were then biased to see if movement had any effect on the leakage current (large effects were observed in 2021 beamtime). Movement of the pneumatics saw no observable change in the leakage current above normal fluctuations. 

Both motors arms had been sucked into the chamber by 5-10mm due to the vacuum before starting the movement cycle. After one movement cycle, the motors returned to their normal fully out positions and remained fully out. 

26/06/23

This morning the pressure was 4e-7 mbar. The bolts on the windows and the large flange on the bottom of the interaction chamber were tightend. No leak was present on the windows following tightening. However, the leak on the rotatable flange, although decreased in magnitude, was still in the 1e-9 mbar l/s range when helium was sprayed. The torque on these bolts was 36 Nm, which is already past the 33 Nm recommendation for M8 bolts. It was decided to vent the section and examine the flange. 

Tomorrow morning the gasket will be replaced and we will begin pumping again in the afternoon. 

27/06/23

Flange was removed and examined. Several scratches on the surface of the flange including on the knife edge were visible. These scratches were sanded away by the grossmontage and the flange was remounted. CARME was pumped down in the afternoon. Pressure was in the 1.5E-3 mbar range when the scroll pump stalled causing the pressure to increase and the turbo to increase in current to keep up. Error symbol was observed on the scroll, unknown to why it stalled. VAT gate valve to the chamber was closed and all pumps turned off to be safe, P~ 1mbar. 

28/06/23

Jan started the scroll pump on  just the backing line using the gas balast to see if too much water was pumped. Scroll running fine so the gate valve to the chamber was opened and the turbo started. 

09.00 CARME IE514 5.1e-11mbar

09.15 IE514 not working - one of cables disconnected?

      DSSSD #1 bias cable changed from SHV - Lemo 00.250 to SHV - 2x Lemo 00.250

      DSSSD #1 & #2 LK1 removed from n+n Ohmic side bias FEE64s

      aida11 HDMI cabling re-seated at MACB

10.26 DSSSD bias OK - attachment 1
      Ambient temperature +16.2 deg C

10.30 ADC data item stats OK - attachment 2
      aida06 & aida15 > 100k, all others c. 3k consistent with 50Hz pulser

10.34 per FEE64 Rate spectra - attachment 3
       OK except for known issues aida05, aida07 and aida16 - all others OK

      per p+n FEE64s 1.8.L spectra - attachment 4
       pulser peak width 52 ch FWHM aida11- double peaking DSSSD #1 & #2

      per n+n FEE64s 1.8.L spectra - attachment 7
       pulser peak width 77 ch FWHM aida04 - more uniform noise across all DSSSDs

10.42 per FEE64 1.8.W spectra - 20us FSR - attachments 5-6

11:00 LK2 removed from aida01-04. Configuration for all adaptor cards/FEE modules is now the same. No other change to the setup.

12:00 FEEs power on, bias to 150 V. No change in bias observed. 

12.02 ADC data item stats OK 
      aida06 & aida15 > 100k, all others c. 3k consistent with 50Hz pulser

12.07 per FEE64 Rate spectra 
       OK except for known issues aida05, aida07 and aida16 - all others OK
      
12:09  per p+n FEE64s 1.8.L spectra 
       We now observe a large peak around chn 30,000 on all FEEs. Perhaps an effect of some change in the ring?
       pulser peak width 53 ch FWHM aida11- still observe double peaking DSSSD #1 & #2

      per n+n FEE64s 1.8.L spectra 
      Lots of events at ~chn 65,000 - double peaking now observed on aida03 and aida04
      pulser peak width 93 ch FWHM aida14 

12.20 per FEE64 1.8.W spectra - 20us FSR 

      Perhaps bias was off while acquiring and spectra was not cleared properly. Re-do tests

13:40 ADC data item stats OK - attachment 7 
      aida06 & aida15 > 100k, all others c. 3k consistent with 50Hz pulser

       per FEE64 Rate spectra - attachment 8
       OK except for known issues aida05, aida07 and aida16 - all others OK

      per p+n FEE64s 1.8.L spectra - attachment 9 
       pulser peak width 55 ch FWHM aida11- double peaking DSSSD #1 & #2

      per n+n FEE64s 1.8.L spectra - attachment 10
       pulser peak width 65 ch FWHM aida14 - more uniform noise across all DSSSDs

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

      With help from NH updated firmware on all MACB modules to version 4/20 - see https://elog.ph.ed.ac.uk/CARME/482

      Timestamps for all FEE modules now correct - attachment 13

      MAC address of aida07 was found to be 41-b4-16 not 41-d4-16 as was labelled on the FEE module
       re-labelled FEE64
       dhcpd.conf and MIDAS startup.tcl updated, dhcpd and MIDAS 8015 server restarted - aida07 is now working OK
 
      CAEN N1419ET internal jumper fitted - outputs are no longer floating

15:20 ADC data item stats OK 
      aida06 & aida15 > 100k, all others c. 3k consistent with 50Hz pulser - attachment 14

       per FEE64 Rate spectra
       OK except for known issues aida05, and aida16 - all others OK  - attachment 15

      per p+n FEE64s 1.8.L spectra -
       pulser peak width 50 ch FWHM aida11- double peaking DSSSD #1 & #2 - attachment 16

      per n+n FEE64s 1.8.L spectra 
       pulser peak width 67 ch FWHM aida14 - more uniform noise across all DSSSDs

       per FEE64 1.8.W spectra - 20us FSR - aida14 missing from waveforms - attachments 17,18
 
   Swapped the test inputs so that +ve is now from the inverter and -ve direct from pulser.  - attachments 19,20. Observed reduced noise for when plugged directly into the pulser than when connected from the inverter. 



   Lowered threshold from 0x64 (1 MeV) to 0x20 (320 keV) - attachment 21, 22 - Observed increase in rates, in particular for the DSSD #1,2 pn side. Conclusion -> increased pulser width for DSSD #1,2 is real and not from the pulser
 


   aida01 lemo to water pipe (chamber ground) connection installed 

   ADC data item stats OK 
      aida06 & aida15 > 100k, all others c. 3k consistent with 50Hz pulser 

       per FEE64 Rate spectra
       OK except for known issues aida16 - all others OK 

      per p+n FEE64s 1.8.L spectra -
       pulser peak width 48 ch FWHM aida11- double peaking DSSSD #1 & #2 - attachment 23

      per n+n FEE64s 1.8.L spectra 
       pulser peak width 67 ch FWHM aida14 - attachment 24

       per FEE64 1.8.W spectra - 20us FSR - slightly reduced 100 kHz on pn waveforms - attachments 25,26

   Disconnected aida06 and replaced with the spare FEE module (mac address: 42:0d:16). Power cycled and updated config files. 

   ADC data item stats OK 
      aida15 > 100k, all others including aida06 c. 3k consistent with 50Hz pulser - attachment 27

       per FEE64 Rate spectra
       OK except for known issues aida16 - all others OK - attachment 28

      per p+n FEE64s 1.8.L spectra -
       pulser peak width 48 ch FWHM aida11- no longer observe double peaking DSSSD #1 & #2 but the pulser peaks are still broader compared to DSSD #3,4 - attachment 29

      per n+n FEE64s 1.8.L spectra 
       pulser peak width 55 ch FWHM aida14 - attachment 30

       per FEE64 1.8.W spectra - 20us FSR - greatly reduced 100 kHz on pn waveforms, dodgy FEE previously aida06 must@ve had some impact on DSSD#1,2 - attachments 31,32
      

Removed ground from DSSD #1 to the chamber and set MACBs so that timestamp is from the NIM WR emulator not the VME VETAR2.

Root MACB mode 0x3 -> 0xd - all other MACB modes 0x3 ( unchanged ).

No timestamps observed from the emulator. Re-set to take timestamps from the VETAR" unit -> all timestamps observed.

10:30

No pulser observed in nn FEE modules 9, 10, 13, 14.

ADC data items check OK - all ~3k - attachment 2

Rates - all OK  - attachment 3

1.8L spectra. - attachment 4,5

1.8W waveforms - attachment 6,7

11:00

Checked daisy chain which goes from 8->14->13->10->9. Replaced the lemo cable from 8->14 and pulsers re-appear. Rates all OK except aida10 which has now disappeared, tried asic check and reset and startup again no change in aida10.

Now majority of pulsers are observable the widths will be noted in a spreadsheet

After replacing lemo for nn pulser chain, all nn pulser widths decreased slightly ~10% for all nn FEEs, little change in pn pulser widths but n pulser for DSSD#1,2 appears more gaussian

11:44

FEE64s power cycled. aida10 now prioducing data.

Removed internal jumper from CAEN N1419ET 

ADC data items check OK - all ~3k - attachment 8

Rates - all OK  - attachment 9

1.8L spectra - attachment 10,11 little change in pn pulser widths but nn pulser widths are slightly broader.

1.8W waveforms - attachment 12,13

15:50 Jumper re-mounted onto caen bias module

ADC data items check OK - all ~3k - attachment 14

Rates - all OK  - attachment 15

1.8L spectra - attachment 16,17

1.8W waveforms - attachment 18,19

16:45 Ground cables attached from water pipe (chamber ground) to lemo cable on aida08 (nn), aida13 (nn), aida09 (nn), aida01 (pn) so that all DSSDs are connected to chamber ground.

ADC data items check OK - all ~3k - attachment 20

Rates - all OK  - attachment 21

1.8L spectra - attachment 22,23

1.8W waveforms - attachment 24,25

ASIC settings for the pn FEEs has been reset to the default aida settings. This was done to combat the observed dropping of several  channels in pn only FEE modules 
following motors movement. This effect was also observed in 2022 in several pulser walkthroughs conducted pre and post detector movement. No dropped channels were 
observed in nn FEEs. 

ASIC seetings changed;

IBias LF feedback from 0xf to 0x8
diode link threshold from 0xbf to 0xca

We also set the slow comparatort for all FEE modules back to 0x64 (1 MeV)

Settings tested using only 2 pn FEE modules (aida05 and aida16). Movement left and right. Dropped channels observed in all pn FEEs except aida05 and aida16. All pn ASIC 
settings then changed. Movement for 10 repeptitions. No dropped channels observed in pn FEEs. 

New settings saved in 2024Feb08-15.59.09

15:30

Waiting for the target to cool down. ETA is 16:30 for cooling to be finished and then we need to try and make target.

While waiting we havve been running a background (R3). I noticed the rates on aida10 had increased (300k) and aida09 were slowlly creeping up too. Check load and shaking the detectors did not work. These FEEs correspond to the high leakage current detectors and showed similar rates to aida03 and aida04 which were turned to MEC.

Tried some tests. Lowered bias voltage to 50V. Rates increased on aida09 and aida10. Increased voltage to 110V and rates dropped to approx zero. Checked 105V and we get the same effect as at 110V. 

Then decided to try to increase the bias on DSSD1 as well. 110V no ffect but at 115V we see the rates drop to zero.

Data rates of ~300 kB/sec writing to disk.

Some increases in rates on aida12 have also been noticed. We have turned the fast discrimtor off for this FEE which has resolved the issue. We should keep an eye on the rates as we hope this is stable but may not be.

 Attachment 1 - current ADC data items rate with new settings. (still 0x32 slow comparator, all channels LEC)

Attachment 2 - aida12 discriminator settings.

Attachment 3 - current bias/leakage current values.

Started R4 - background we expect beam in the ring soon.

16:00

Beam is in the ring - we see the beam stripe on DSSD1

No change on data rate writing to disk or in ADC statistics rate.

Motors fully out. Left potentiometer = 18.86 mm, Right potentiometer = 19.80 mm

Beam energy = 2 MeV/u - 6Li1+

Cycle time is 25 seconds

Attachment 4 - CARME detectors xy plot

Attachment 5 - Total energy histograms (Ex)

17:56

Nikos requires access to the cave so beam is stopped and background run is going.

R5 started. Same settings as previous run.

21:45

All system checks OK - except white rabbit decoder and FPGA timestamps see attachments 6,7

Data rate had gone high again ~2 MB/sec. No difference on ADC data items. Large increase on aida06 for aida disc info #6.

Checked hit rate for aida06 and see ASIC 2 was misbehaving. ASIC check load on asic 2 -> problem sorted. This is not first time this has happened. We should keep an eye on the data rate.

New run 61

Right arm at 64.60 mm

Left arm IN at 36.54 mm

MBS working - hopefully

Target 4E11

Injection ca. 3E7

horizontal beam position 8.75 mm

vertical beam position  -5mm

Changed electron cooler set point to 244.95 V

Read value 244.4 V

Collector current 4.31A

Histograms and statistics zero'd. Code reset

Rates OK. Temps OK.

10:24

We lost the beam for 5 minutes. No counting spike observed when we got it back.

1L10

We lost the beam again for 5 minutes, but no counting spike obsevered when we got it back.

11:50


      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 - ~ 3.3E7 pps

      Target density - 5.14E11 atoms/cm2

12:00 - 12:40

Large fluctuations in the target pressure, going down to 1e-9. We increased the temperature a little but it did not solve the problem.

Increased pressure 0.5 K more. Seems more stable

13:09

FEEs on det 2 stopped working. Checkloaded. Fixed.

No beam.

17:20

(Run 87 Junk and Run 88 does not exist)

Beam charge state set to 5+. Energy is ~1.06 MeV/u

Cooler voltage setpoint 590.3 V.

FC20 read value 589.07 V.

Right arm at 64.60 mm

Left arm IN at 36.54 mm

FakeMotion script running

horizontal beam position 3.5 mm (new overlap position with new beam)

vertical beam position  0.0 mm

Beam intensity 7.0e+6 particles.

Target density ~5e11 at/cm2

Beam is stored in the ring for ~20 seconds. From beam overlap tests ~ 75% of the beam is destroyed in this time.

Beam halo appears slightly reduced. This may be due to reduced intensity and reduced injection rate (20 s vs 5s previously)

18:00

FEE64 temperatures OK

ADC data item stats OK

per FEE64 Rate spectra OK

Beam intensity 1.17e+7 particles

Target density ~5.25E11 atoms/cm2

20:28

FEE64 temperatures OK

ADC data item stats OK

per FEE64 Rate spectra OK

Beam intensity 1.08e+7 particles

Target density ~3.84E11 atoms/cm2

23:58

Temps OK. Stats OK. Merger OK. Write to disk OK.

Waveforms attached.

Beam keeps going away due to "solenoid" issues.

On-line analysis screenshots attached.

Without beam, we see a clear noise spike in all detectors every 50-200 seconds randomly. This is *not* correlated with beam injection or dump.

Checkloaded - no effect. Beam back - no changes.