Every 30 minutes:

- Reload statistics (Web browser tab screen 1, workspace 3)
    - Are all FEEs still showing a rate?
    - If one shows 0 after multiple reloads Call Oscar or Tom.

- IGNORE FOR TIME BEING Options database monitor (Top middle terminal screen 2, workspace 3)
    - Has the message changed since the last check?
    - If so copy the message and place in elog

- Do the ucesb scalers make sense? (Web browser, screen 2, workspace 5)
    - If one DSSD is reporting kHz of implants when the others are much less it is likely an ASIC getting stuck.
    - Perform and ASIC check (ASIC control tab, web browser, screen 1, workspace 3)
        - Ensure "Act on all FEE" and "Act on all asic" selected
        - Click on drop down menu in the bottom of the screen and select check ASIC control
        - It will take a minute or so be patient (MIDAS can only respond to one command at once so don't try to do anything else)
        - A pop up will appear check that all options say ok
        - Has the implant rate gone to a more normal amount?
            - If not feel free to call

Every two hours:

- Take a screenshot of the statistics page (Web browser tab screen 1, workspace 3)
     - Compare to the previous screenshot to check if anything has drastically changed

- Take a screenshot of the temperatures (Web browser tab screen 1, workspace 3)
     - Do they all appear stable?

- Take a screenshot of the bias and leakage currents - (Top left terminal, screen 2, workspace 3)

- Perform the five system wide checks (Web browser tab screen 1, workspace 3)
     - Ignore the system wide checks for ADC calibration (ADCs are turned off so they will all fail)
     - Check memory information also fails.
     - Make a note in the elog of which tests are successful
     - If failed copy the text from the white box into the elog and make a note of it

- Enter the screenshots into the elog

- Update the leakage current spreadsheet (Web browser, screen 2, workspace 5)

Runs are in /TapeData/BGAPR22 located on 8TB disk "SecondDrive" (N.B. 2A experiment is using ThirdDrive)

Old runs and test files were removed from disk. Left is an unknown S481 folder (fibre implant test?) and Patrick
chown to npg:npg as uid changed from old SL6 to CentOS 7

Bias DSSDs, leakage current higher than before (maybe the sheet isn't covering the snout)
Pulser set to OFF
ASIC Thresholds 0x64, rates mostly 0 (good)
Edge strips on aida02 and aida06 show non zero, and lots in aida04 asic 1 are high, will recheck connector tomorrow in hope

Connecting to merger and rate is 60k items/sec with random jumps to 400k items/sec
Start xfer to tape server: Rate approx 100 KB/s (360 MB per hour, 2.88 GB per 8 hours)

19:51 - Will leave overnight running to collect alpha

Fri 29 Apr

14:38 - Run paused for MBS tests with FRS

16:50 - Resume alpha collection over weekend
Pulser OFF, 0x64 thresholds

Remount snout in S4 (photos to come) 
Alignment with DEGAS OK but a bit short...  DEGAS platform will be brought 31 mm closer to AIDA by rail adjustment

Can mount bPlas booster boards on old ITEM frames and also partly on AIDA snout (isolated)

-

Reconnect all adapter boards and grounds, bias AIDA...

HV OK. We still have a light leak at the snout endcap. "Fixed" with sheet for now

HV leakage currents figure 1

Start AIDA DAQ and check rates.. all seem OK. aida07 is very noisy other p+n good
Notice some issues in aida04, check and ribbon cable slightly loose on one side of adapter
No change to other FEEs.
Aida07 was inspected but nothing obviously wrong

Rates figure 2
Rate spectra figure 3
Wavesform figures 4 (p+n), 5 (n+n)
Pulser peak withs
 p+n figure 6, width ~  70 channels (50 keV)
 n+n figure 7, width ~ 570 channels (400 keV)

n.b. double peak in aida14 is an artifact from an uncleared histogram

DSSDs debiased to allow work on bPlas cabling without tripping DSSDs

09:59 Noticed that the right hand ribbon cable for aida07 was offset vertically by 1. i.e. Only 1 of the 2 rows of pins in. Unbiassed detectors and reconnected.
      Rebiassed detectors - leakage current on DSSD2 increased to 9.96uA - Attachment 1

      Power cycling FEEs

      Following restart the FEEs show some improvement in rates - attachment 2
      Rate spectra - attachment 3
      Still issues with aida11 in the rate spectra (Likely a misaligned ERNI connector)



      Pulser on rate spectra - attachment 4
      Pulser off rate spectra - attachment 5
      We can see that with the pulser on there are events in the channels in aida01 and aida11
      With the pulser off these channels disappear.
      ERNI connector is then likely aligned the issue is more likely the DSSD ribbon cable is misaligned.

      Taking bias off to investigate.


10:39 Could not observe anything out of alignement about either the connectors or the adaptor boards
      Note that after pushing on the connector AIDA01 had largely recovered

13:30 Top of snout taken off while mounted in S4. It was observed that one of the ribbon cables for aida11 was off by 1 row.
      This was corrected in situ and the snout was put back together and made light tight again.
      Oddly leakage current still the same - DSSD2 has come down though - attachment 6
      FEEs powercycled for new tests

      Half the channels in aida11 had appeared again
      Took apart once more and found the other header also off by one row which has been corrected

      FEEs powercycled for new test

      All of aida11 now showing - attachment 7
      Statistics at 0xa shown in attachment 8
      All p+n for DSSD1 are good (aida01, 03, 09, 10, 11 and 12)
      p+n for DSSD2 are so so (aida05, 07, 13, 14, 15 and 16)
      All n+n 2, 4, 6 and 8 are poor still


14:50 p+n waveforms - attachment 9
      n+n waveforms - attachment 10

      Current jumper configuration
      LK1 (Bias ground) on FEEs 6 and 8
      LK2&4 on all p+n
      LK3 on aida03 and aida07 (Bottom middle)

15:00 Investigated whether there was a light leak. Placed black material over snout.
      Leakage on DSSD2 dropped to 5.6 - attachment 11
      There was a light leak
      Stats have decreased slightly - attachment 12

16:00 Move raspberry pis atop 5mm alminimum plate to keep away from FEE64 PSUs
      No change

16:30 Remove pulser network from all FEEs 
      Rates get noticably worse in many FEEs... why?
      Stats - attachment 13

      Possible ideas include braid touching things it shouldn't (Adapter PCBs?) 

Re-assembled triple snout re-installed on the AIDA stand - DSSSD ribbon cables and grounds re-connected.
FEE64 adaptor PCB LKs per https://elog.ph.ed.ac.uk/DESPEC/409

Attachments 1 & 2 1.8.L spectra
  p+n FEE64 aida10 pulser peak width 97 ch FWHM
  n+n FEE64 aida04 pulser peak width 550 ch FWHM

Attachment 3 rate spectra
  missing channels aida01, aida07 & aida11 - misaligned ERNI and/or Samtec connectors?

Attachments 4 & 5 1.8.W spectra 

Attachment 6 ADC data item rates
 aida10 OK, all others c. 300-400k

Attachment 7 FEE64 temperatures OK

Attachment 8 DSSSD bias & leakage currents OK

DSSSD bias OFF. DAQ STOPped

Attachment 6 FEE64 temps OK

Attachment 1-5 system wide checks OK 

OH/NH disassembling current AIDA triple snout and DSSSD stack.

Length of ribbon cables (including connector) outside snout as follows

p+n junction side 9cm & 15cm
n+n ohmic side 10.5cm & 16cm 


Update
p+n junction side: 6.5cm, 10.5 cm (used  7.5, 11.5 for 1cm slack)
n+n ohmic side:  11.0 cm, 15.0 cm (used 12.0, 16.0 for 1cm slack)
Measurement from SAMTEC connector to exit from the rubber seals in AIDA snout.

DSSSD bias OFF. DAQ STOPped

Attachment 1 FEE64 temps OK

Attachment 2 system wide checks OK *except* WR decoder (attachment 2) and FPGA ts errors no longer works

Attachment 6 System wide check - 'Synchronise ASIC clocks'

Attachment 5 System wide check - check ADC calibration - all 16x FEE64s fail

Attachment 4 System wide check - WR decoder status - aida09 WR status 0x10 clears

Repeat Synchronsie ASIC clocks

Attachment 3 System wide check - WR decoder status - aida05 WR status 0x10 clears
             

AIDA adaptor PCB config - all LKs removed *except*

aida04 & aida08 LK1

aida02 & aida07 LK2, LK3 & LK4

aida09, aida01, aida10, aida11, aida15, aida12 & aida16 LK2 & LK4



10.05 check all ASICs all FEE64s
      zero histograms

Attachment 1 per FEE64 rate spectra

Attachment 2 per FEE64 p+n 1.8.L spectra - aida10 peak width 79 ch FWHM

Attachment 3 per FEE64 p+n 1.8.W spectra 20us FSR

Attachment 4 per FEE64 n+n 1.8.W spectra 20us FSR

Attachments 5-8 - system wide checks - all OK *except*

  FPGA timestamp errors no longer works
  aida05 & aida09 report WR decoder error 0x10

Attachment 9 ADC data item stats

Attachment 10 FEE64 temps OK

Attachment 11 DSSSD bias & leakage current OK

Attachment 12 per FEE64 n+n 1.8.L spectra - aida08 peak width 369 ch FWHM


14.25 DAQ STOP
      DSSSD bias OFF

      AIDA triple snout removed from AIDA stand and moved to table by aida-gsi (Messeheute)

all system wide checks OK *except* aida10 failed ADC calibration

Attachment 1 ADC data item stats
Attachment 2 FEE64 temps OK
Attachment 3 DSSSD bias & leakage currents OK





DSSSD bias to left (looking upstream) wafer *only*
      FEE64s 10 & 12, 14 & 16

Attachments 4 & 5 1.8.W spectra 20us FSR

Attachment 6 ADC data item stats

Attachment 7 DSSSD bias & leakage current




ASIC check all FEE64s

DSSSD bias to middle (looking upstream) wafer *only*
      FEE64s 1 & 3, 5 & 7

Attachments 8 & 9 1.8.W spectra 20us FSR

Attachment 10 ADC data item stats

Attachment 11 DSSSD bias & leakage current





ASIC check all FEE64s

DSSSD bias to right (looking upstream) wafer *only*
      FEE64s 9 & 11, 13 & 15

Attachments 12 & 13 1.8.W spectra 20us FSR

Attachment 14 ADC data item stats

Attachment 15 DSSSD bias & leakage current



Conclusions

ADC data item stats -> 300-400k

n+n 1.8.W spectra show large signal excursions

p+n 1.8.W spectra for biased Si wafers OK - unbiased Si wafers show large signal excursions


DSSSD#1 leakage currents 1.850+2.220+1.990=6.06uA    cf. 5.095uA with all 3 wafers biased 
DSSSD#2 leakage currents 1.510+1.580+2.350=5.44uA    cf. 5.235uA 


Right wafer (looking upstream)
             
Bias(V)         -20    -40    -60    -80    -100
DSSSD#1 I_L(uA) -1.135 -1.475 -1.645 -1.750 -1.805
DSSSD#2 I_l(uA) -1.625 -2.020 -2.205 -2.320 -2.360

Middle wafer (looking upstream)
          
Bias(V)         -20    -40    -60    -80    -100
DSSSD#1 I_L(uA) -1.540 -1.870 -2.035 -2.150 -2.210
DSSSD#2 I_l(uA) -0.985 -1.285 -1.465 -1.575 -1.615

Left wafer (looking upstream)
          
Bias(V)         -20    -40    -60    -80    -100
DSSSD#1 I_L(uA) -0.735 -0.915 -1.005 -1.080 -1.110
DSSSD#2 I_l(uA) -0.865 -1.205 -1.400 -1.510 -1.560

Bias versus leakage cuurent characteristic of each wafer of each DSSSD indicates diode behaviour.

Note LK1 not fitted - presumably LK3 of mid/top p+n FEE64 adaptor PCBs (aida01 and aida05) connecting n+n bias to gnd is sufficient to establish circuit.




15.50 Re-connect bias to all 3x Si wafers p+n junction side bias rings

ASIC check all FEE64s

Attachments 16 & 17 1.8.W spectra 20us FSR

Attachment 18 ADC data item stats

Attachment 19 DSSSD bias & leakage current

Conclusion - status quo ante restored



16.40 Remove aida01 & aida05 LK3, add aida04 & aida08 LK1

ASIC check all FEE64s

Attachments 20 & 21 1.8.W spectra 20us FSR

Attachment 22 ADC data item stats

Attachment 23 DSSSD bias & leakage current

Conclusion - no change



17.00 Add Thorn-Lab HV filters DSSSD#1 & #2


ASIC check all FEE64s

Attachments 24 & 25 1.8.W spectra 20us FSR

Attachment 26 ADC data item stats

Attachment 27 DSSSD bias & leakage current

Conclusion - aida09-aida12 no change, aida13-aida16 -> 300-400k
             I do not know why there's a difference between DSSSD#1 & #2 but more important point (probably) no improvement aida09-aida12
             Thorn Lab HV filters removed - status quo ante restored


18.02 Remove LK2 & LK4 all top p+n adaptor PCBs (aida13, 5, 14, 9, 1, & 10)

ASIC check all FEE64s

Attachments 28 & 29 1.8.W spectra 20us FSR

Attachment 30 ADC data item stats

Attachment 31 DSSSD bias & leakage current

Conclusion - no change cf. 16.40 test



19.10 Re-order power cabling at AIDA FEE64 PSUs from ...

Top    1-3 2-4 9-10 11-12
Bottom 5-7 6-8 13-14 15-16

to ...

Top    1-2 3-4 9-10 11-12
Bottom 5-6 7-8 13-14 15-16


ASIC check all FEE64s

Attachments 32 & 33 1.8.W spectra 20us FSR

Attachment 34 ADC data item stats

Attachment 35 DSSSD bias & leakage current

Conclusion - all p+n FEE64 rates c. 100k, or less, n+n FEE64 rates c. 400k

FEE64 adaptor PCB config

LK2-LK3-LK4 fitted for all bottom p+n FEE64s (aida11, 3, 12, 15, 7, 16)

LK1 fitted n+n FEE64s aida06 & aida02 *only*

11.10 Found aida08 not running - merger/TapeServer stalled

Restart required power cycle of all FEE64s
*all* ADC calibrations failed during system wide checks it was necessary to use FADC align & control (act on all FEE64 modules selected) to calibrate - first pass 
12/16 calibrated, successive individual re-calibrations calibrated remaining FEE64s

ASIC settings 2021Apr29-13-16-00
 slow comparator 0x2f

BNC PB-5
amplitude 1.0V
attenuation x1
polarity +
tail pulse
tau_d 1ms
rate 25Hz

Attachments 1-4 1.8.W n+n spectra 20us, 200us, 2ms, 20ms FSR
Attachments 5-8 1.8.W p+n spectra 20ms, 2ms, 200us, 20us FSR

Attachment 9 per FEE64 1.8.L spectra n+n strips
 aida04 pulser peak width 387 ch FWHM
Attachment 10 per FEE64 1.8.L spectra p+n strips
 aida10 pulser peak width 93 ch FWHM

Attachment 11 per FEE64 Rate spectra

Attachments 12-15 all system wide checks OK
Attachment 16 ADC data item stats
Attachment 17 FEE64 temps OK
Attachment 18 DSSSD bias & leakage currents OK

15.45 check of ASIC settings cf. https://www2.ph.ed.ac.uk/~td/AIDA/Information/Default%20AIDA%20ASIC%20Parameters.txt

Differences from default AIDA ASIC parameters
--------------------------------------------- 

                                            Input Polarity
Offset Title                                Positive   Negative            Notes

12     slow comparator threshold            0x2f->0xa                     100keV nominal
 
14     fast comparator threshold HEC        0xf->0x02                     200MeV nominal
15     fast comparator threshold LEC/MEC    0xf->0xff                     > LEC/MEC nominal FSR

18     preAmp reference                     0xb2       0x20->0x30

21     Ibias LF feedback                    0x08       0xb->0xf

26     diode link threshold                 0xca->0xbf 0x11->0x23         decrease switch threshold

(front) p+n junction strips - positive input polarity
(back) n+n ohmic strips - negative input polarity

All looks OK - variations from default settings are those used at RIKEN

16:45 FEE64 adaptor PCB config

    LK1 LK2 LK3 LK4
p+n n/c o   *   o
n+n o   o   n/c o

o   = jumper fitted
n/c = jumper not fitted

*   = top, middle FEE64s - n+n bias ring ground for Si wafer #2
      bottom, middle FEE64s - DSSSD PCB gnd

DSSSD#1 & #2 bias via standard coaxial cable to top p+n FEE64 adaptor PCBs

17.05 aida09 or aida13 cable braid not secured to ground - cable tag dia too large - now sandwiched between correctly sized cable tags 
      no obvious difference to adc data item rates


17.20 LK1 removed for all n+n PCBs
      attachment 19 - adc data item stats

18.55 LK2/LK4 removed for all n+n PCBs
      attachment 20 - adc data item stats

19.10 power cycle FEE64s
      attachment 21 - adc data item stats

11.15 - S4 is currently closed no access

If access possible (should be) plan is

Re-attach ribbon cable braids
Re-attach DSSSD middle wafer rear g/r (LK3)
Re-attach DSSSD ground (LK2?)

See difference in rates, expectation is braid should restore most p+n rates

Once status quo ante achieved explore ASIC settings to identify preamp feedback and shaping time options to stabilise preamp output and optimise signal:noise.

aida12 Peak width =    84.73
aida02 Peak width =   526.68
Attachment 1 - Stats
Attachment 2 - Per FEE Rates
Attachments 3,4 - Waveforms
Attachments 5,6 - Pulser Peaks
Attachment 7 - HV Bias. Leakage current recovered and does not seem to be ramping up

16.00 - Attach LK3 jumpers to aidas 1, 3, 5, 7 (DSSD ground and middle rear g/r)

Attachment 8 - Stats
Attachment 9 - Per FEE Rates
Attachment 10, 11 - Waveforms
Attachment 12, 13 - Pulser Peaks

aida12 Peak width =    78.51
aida02 Peak width =   480.90

No major change, FEES 1-8 are all noisy and FEES 9-16 are quiet
aida01, aida05 waveforms very noticably bad (100 kHz), aida03, aida07 waveforms seem OK


16.45 - Attach LK2, LK4 jumpers to all FEEs (field plane grounding)
No significant changes

Attachment 14 - Stats
Attachment 15 - Per FEE Rates
Attachment 16, 17 - Pulser Peaks
Attachment 18, 19 - Waveforms

aida12 Peak width =    71.28
aida02 Peak width =   458.18

Remove LK3 jumpers 

aida12 Peak width =    71.43 
aida02 Peak width =   496.05


Attachment 20 - Stats
Attachment 21 - Per FEE Rates
Attachment 22, 23 - Pulser Peaks
Attachment 24, 25 - Waveforms

Re-add jumpers - attachments 26-28

aida12 Peak width =    87.42
aida02 Peak width =   572.24

17.45 Directly bias from the p+n FEEs using SHV->BNC->Lemo - attachments 29-33

aida12 Peak width =    87.87
aida02 Peak width =   504.41

The correlation between high 'ADC data item' rate and the noise observed on the corresponding 1.8.W spectrum is not clear *except* for aida01 & aida05 - see also attachments 34-35

ADC data item stats - attachment 36

DSSSD bias & leakage current OK - attachment 37

FEE64 temperatures OK - attachment 38

all system wide checks OK *except aida11 clock fail status 6

11.25 System wide checks OK except aida06 clock fail status 6 - attachments 1-13

      ADC data item stats - attachment 14

      FEE64 temperatures OK - attachment 15

      DSSSD bias & leakage currents - attachment 16
  
      DSSSD#1 OK. DSSSD#2 leakage current has increased from c.5uA to c. 11uA overnight.


11.43 per FEE64 1.8.W spectra - 20us, 200us, 2ms, 20ms FSR - attachments 17-24

      per FEE64 1.8.L spectra - attachments 25-26
          aida12 1.8.L pulser peak width 143 ch FWHM
          aida02 1.8.L pulser peak width 439 ch FWHM

      Per FEE64 rate spectra - attachment 27

12.00 Cycled DSSSD#2 bias from -100V to 0 to -100V leakage current -7.7uA but ramping slowly (c. 5nA/10s ... ?)

13.26 DSSSD#2 bias -100V leakage current -8.54uA

15.46 - Noticed that DSSSD#1 braid no longer has filter, DSSSD#1 core still does. DSSSD#2 is unfiltered on both.

      - Swap FEE64 power connectors #3 with #4, and #6 with #7, this means both n+n FEE64s are on the same paired channel

      No significant change to stats

      - Notice braid was only connected to FEEs 4 and 8, which meant beam-left bias guard ring 0v was floating. Use T to bring bias braid over to FEES 2 and 6 as well.
        Middle bias guard ring 0v is still floating

      No significant change to stats, amplitude of 100 kHz waveform in n+n waves seems attenuated though

     aida12 1.8.L pulser peak width 76 ch FWHM
     aida02 1.8.L pulser peak width 438 ch FWHM
 
     Attachment 28 - HV leakage current
     Attachment 29 - FEE ADC stats
     Attachment 30 - p+n side waveforms
     Attachment 31 - n+n side waveforms
     Attachment 32 - p+n pulser peak widths
     Attachment 33 - n+n pulser peak widths

15.55 - Reattach filter to DSSSD#1 braid

     No major change, possible improvement in waveforms 
     Attachment 34 - Stats
     Attachment 35,36 - waveforms

16.46 - Reattach LK1 jumper to FEES 2, 4, 6, 8

     Waveforms look OK, p+n rate slightly worse?
     Attachment 37 - Stats
     Attachment 38, 39 - waveforms
     Attachment 40 - Per FEE Rates

Tests performed

• After leaving overnight noticed the pulser was not fully inserted into aida09
  • Little change in rates observed in 9 but otherwise nothing else
• Connected bias of aida02 (n+n ground) to aida06 (n+n ground) and likewise 4-8
  • No change observed in rates
• Also tested covering the snout in light tight material
  • No Changes
• Unplugged the system monitor from 6 and 8, no change
• Connected the snout to ground with copper tape
  • Rates became very unpredictable in the FEEs unsure if this was snout grounding related though
  • Removed the ground and powercycled and rates restored to where previously
• Changed the bias supply jumper inside to have the bias line connected to the rack ground
  • At the same time noticed that the ground cable connecting the adaptor board of aida06 to the FEE had become disconnected from the ring terminal
    • Recrimped and inserted again
  • Saw an improvment in the rates of the p+n strips and also the n+n strips - attachment 1
  • Pulser widths however larger than yesterday

p+n width

n+n width

• Connected up entire pulser circuit to n+n FEEs

Switching bias supply back

• because changes were made to the n+n ground, and the pulser circuit it was decided to go back and check the previous bias configuration with the module set in a floating configuration
• DAQ was then left overnight as had to leave to catch the bus
• Rates are observed to be back at their higher values - attachment 2
• n+n 1.8.L spectra - attachment 3
• p+n 1.8.L spectra - attachment 4

p+n widths

n+n widths

• The results show no improvment to slightly worse performance so will go back to having the bias module grounded internally and check the previous conclusions hold before making further changes

Return to grounded bias module

Widths

p+n

n+n

• Don't see a pulser peak in 4 or 2
• Will replace cable between 4 and 2 and 2 and 6
• Statistics at 0x64 with pulser on - atachment 5
• Now see peaks - attachment 6
• Statistics at 0xa - attachment 7

With the grounded bias in place in the module move the braid cable to the frame rather than being connected to bias line

• Still observe a triple peak in 4 and have worse perfromance in 2 and no improvement in p+n
• 0x64 stats - attachment 7
• 0xa statistics - attachment 8
• p+n 1.8.L - attachment 9
• p+n waveform - attachment 10
• n+n waveform - attachment 11
  • Same high frequency component in both
  • 35 channel spacing corresponds to a frequency of ~1.4MHz

Next tests

• Returned braid to FEE 4 and 8
  • Recovered earlier rates and performance
• Re-added the ground cable to the snout
  • Much worse noise performance across all FEEs
  • p+n rates in 200k
• Removed the ground from the snout
  • Got really good rates originally - attachment 12
  • Noticed 1 and 5 failed ADC calibration
  • Calibrated them and there rates increased massively - attachment 13
• Notice that the pulser peak in FEE2 and 6 keeps dropping out
  • As the cables have been changed multiple times thought it could be that an adaptor board was broken
  • 4 seemed the most likely suspect with its high rates and triple peaks
  • Replaced the adaptor board with one missing an outer ERNI pin (PIN doesn't interface with the FEE so didn't see any issues)
  • Pulser peaks were still muissing
  • Issue could be then with adaptor board 2 possibly

Conclusions

• Rates on the FEEs are in a better place now than they were at the start of the week
  • p+n in particular have shown a large amount of improvement
• There are still however issues with the n+n FEEs
• I think there is likely an issue with one of the adaptor boards
  • Possible aida02 at the pulser connection point
  • Could explain the triple peaking in aida04 and the pulser issues with aida02 and aida06 dropping out.
  • Would recomend swapping out aida02 as a test next week
• Other possible issues coiuld be the clingfilm around the cables has torn and we are grounding the cables to the inside of the snout
  • Nic would like to use something other than clingfilm in future
  • One suggestion would be mylar which could be held in place with strips of double sided tape
  • This would make the cables less likely to stick to each other which is an issue with the tightness of the snout
• Could also try removing LK3 from FEE3 and 7 leaving the PCB ground floating
• I am at a slight loss of what else to try

• I have left the daq running at 0x64 overnight to check for alphas
• Histograms and statistics zeroed

Grounding implemented

• Each FEE given direct connection to heavy duty earth bar via adaptor board lemo ground
• Earth bars are then connected to platform ground on AIDA frame
• Photo of grounding - attachment 1
• Improvements not as large as expected from previous experience though
  • Particularly in the n+n side where widths still appear awful
• While implementing the grounding it was noticed the ground lemo socket on FEE7 was damaged and no longer gripped onto a lemo cable
  • It was noted that it would need changing at some point but continued with it for the time being
• Jumper configuration was n+n LK1-4 all on, p+n LK2-4 all on

p+n widths

• Compared to the width with no grounding the FEEs for the first DSSD (First 6) range from no change to slightly worse
• 1.8.L spectra - attachment 3

n+n widths

• Widths still very large
• Width for 8 is around 500
• 1.8.L attachment 2

Additional info

• Statistics - attachment 4

Jumper optimisation

• Went to our previously found optimal jumper configuration for the trips
• n+n LK1 only
• p+n LK 2 and 4 on all FEE
• p+n LK3 on non isolated cables (PCB ground on lower middle cable and n+n side bias on top middle cable)
• While changing the jumpers we also swapped out the damaged adaptor board on aida07 for a new one
• Saw an improvement for most FEEs

• Unfortunately saw no improvement for the n+n
• We event tested having the pulser only going into a single FEE (aida08)
• Still have a width of 622 for that FEE
• To compare FEEs we have layout 1 - attachment 5
• Layouot 1 on a common timescale - attachment 6
  • Note that the rate is typically dominated by a single strip or a couple of strips within a FEE
  • Many channels are just showing the pulser rate 25Hz
• p+n  1.8.L attachment 7
• p+n waveforms attachment 8
• n+n waveforms attachment 9
• Testing the noise on the n+n strips we observe noise with slow comparator set to 200 (2MeV)
• Meanwhile the p+n strips are silent at 0x64 for the most part.
• DAQ left running overnight with 0x64 on ASIC settings to see if we observe any alphas

Plan for the day

• Test daisy chaining the n+n across to the other n+n strips
  • Currently the n+n braid is only plugged into either aida06 or aida08 (depending on DSSD)
  • All of the jumpers are however grounded
  • Will still test
  • May investigate also trying this on LK3 on adaptors for aida01 and aida03
• Observe the output of the new sum inverter on the scope to check for variation in amplitude

Pulser spectra

• Changes to the nn pulser circuit yesterday have improved the peak widths on the p+n side
• p+n peak widths averact around 100 channels
• n+n around 1000 at 0xa threshold
• n+n 1.8.L spectra - attachment 1
• p+n 1.8.L spectra attachment 2

p+n peak widths

n+n peak widths

Daily checks

• Fee temperatures ok - attachment 3
• Bias and leakage currents ok - attachment 4
• Stats spectra with current grounding - attachment 5
  • Current grounding is just a cable going between each adaptor board and its respective FEE
  • Interfee grounding done by power supply and also pulser circuit
• Rates for each of the asics - attachment 6
• p+n waveforms - attachment 7
• n+n waveforms - attachment 8
  • Lots of noise evident on them

Plans for the day

• Connect FEEs up to the copper earth bars installed
• Powercycle and check noise levels
• If n+n remains significantly higher investigate the n+n pulser circuit further
• Investigate the effects of different jumper connetions At present n+n have all LK jumpers on and p+n have lk2-4

An interesting find with the new sum inverter is that with the pulser at default settings the pulser peak on the n+n side is above the range of the ADC.
We have checked signals from the sum inverter and pulser and both are equal in magnitude.
We therefor determine it is over range as the charge is spread over 4 FEEs vs 12 on the p+n side.
This possibly wasn't an issue with the previous inverter if it produced a lower amplitude.

For tests going forward p+n voltage will be 2V. n+n voltage will be 0.5V - Attachment 1
Going to look into a 20dB attenuator

Seems there were issues with the lemo cables in the n+n pulser chain

> DAQ was found yesterday with none of the FEEs reporting any good events on any FEE - attachment 1
> Temperature menu is still responsive and all FEEs report a temperature
> Looking at the white rabbit timestamps aida09 has a gibberish timestamp - attachment 2
> Merger shows no data arriving as expected - Attachment 3
> Merger data buffers for each FEE - attachment 4
> Merger time errors - attachment 5
> 
> DAQ has not yet been restarted in case Patrick wanted to look.

Looking at the first attachment..... aida09 has rebooted. So it is not setup at all.

This has caused the NewMerger to hang .... which surprises me .... as I thought it was designed to spot a bad FEE and continue with the rest.

Yes I will have a look today as I'm in Daresbury.

More later ......

DAQ was found yesterday with none of the FEEs reporting any good events on any FEE - attachment 1
Temperature menu is still responsive and all FEEs report a temperature
Looking at the white rabbit timestamps aida09 has a gibberish timestamp - attachment 2
Merger shows no data arriving as expected - Attachment 3
Merger data buffers for each FEE - attachment 4
Merger time errors - attachment 5

DAQ has not yet been restarted in case Patrick wanted to look.