09:57 Alpha run stoppped R2_0 -> R2_2

      Thresholds dropped from 0x64 to 0xa
      Pulser turned on again
      System wide checks ok
      FEE Temp ok - attachment 1
      Bias ok, leakage at 1.485uA at 160V
      Stats in similar place to yesterday - attachment 2

      Low Energy pulser walkthrough
      1.0V to 0.4V in 0.1V steps
      2 minutes per step
      Pulser at 50Hz
10:29 Run started R3_0

10:45 Run stopped R3_2
      1.8.L spectra for low energy pulser walkthrough - attachment 3

11:00
 High Energy pulser walkthrough
      1.8V to 0.V in 0.2V
      2 minutes per step
      Pulser at 50Hz

11:06 Run started R4_0

10:18 Run stopped R4_2
      1.8.L spectra for high energy pulser walkthrough - attachment 4

On the 18th of September we installed DSSD 3208-14

Was found to have problems including exponential leakage behavior

  V      Ic
 -5   15.4uA
 -10  53uA
 -15  Tripped at over 100uA

Cables were double checked, bond wires were checked and no problems could be observed.

DSSD replaced with 3208-15

Bias at -100V Ic 10.2uA GP/grnd Jumpers removed,
                         rising upwards, possible short circuit as well.

Jumpers replaced

Bias -100V Ic 1.6uA
Bias -160V Ic 1.62uA

Possibility that mechanical sample 3208-17 and 3208-14 have been swapped. (To check at later date)

FEEs powered up and Adapter boards and all grounding installed with DSSD going to 9,10,11 and 12

Rates shown - attachment 1
Waveforms - attachment 2-4
1.8.l Spectra - attachment 5
FEEs 10 and 11 around 60FWHM and 9 and 12 around 80-90FWHM
Stats page - attachment 6

Aluminium foil used to make sure all ports are light tight shows a stats drop of around half - attachment 8

New peak widths

aida09 - 79.65
aida10 - 67.37
aida11 - 59.99
aida12 - 97.83

Going to begin a systematic study of shaping time

                              FWHM
Shaping Time   aida09   aida10   aida11   aida12
   
     8          79.65   67.37    59.99     97.83
     7          97.55   70.84    62.67     115.34
     6         100.72   70.04    62.77     120.05
     4         147.47   80.64    71.34     167.23
     2         217.62   114.98   133.35    232.47

Shaping time 8us 1.8.L Shots 
Shaping time 4us Stats appear obviously worse - attachment 7
                 1.8.L Widths - attachment 8
Shaping time 2us Stats appear worse again - attachment 9
                 1.8.L Widths - attachment 10
Shaping time 6us Stats are better than 2 and 4 - attachment 11
                 1.8.L widths - attachment 12
Shaping time 7us Stats are better than 6 - attachment 13
                 1.8.L widths - attachment 14


8us is the optimum shaping time.
Taken back to 8us and similar shaping times are observed.

Connected the ground of all 4 adapter boards with direct cables. Observed improvements in both FEEs 9 and 12
however the noise in 11 went
through the roof >500kHz - attachment 15

Tested just having 9,10 and 12 connected the rates are comparable to when disconnected - attachment 16

All 4 grounded together with a ground running to the snout as well stats No difference to all 4 together -
attachment 17
              1.8.L Widths - attachment 17
aida09 104.76
aida10 84.58
aida11 281.77
aida12 82.58

Tested just having 10 and 12 directly connected. Same side of the DSSD: Noise is the same as when disconnected.
Stats - attachment 19
1.8.L spectra - attachment 20

aida09 107.13
aida10 67.02
aida11 66.78
aida12 131.51

Tested having 11 and 12 connected directly. This is the two adapter boards responsible for the bias with 11
carrying the core and 12 the braid.
Massively reduced noise in 9 and 12, comparable noise in 10 but much more noise in 11. Stats - attachment 21
aida09 63.96
aida10 76.64
aida11 125.96
aida12 68.05
1.8.L spectra - attachment 23



18:39 Alpha run started in /TapeData/Sep18/R2
      Writing at 96kb/s
      11 Was fast at start bus asic control brought it down




                 

The upstream window of the AIDA detector assembly consists of 2x 50um aluminized mylar

Kernel panics during boot cab be observed in files ttyUSB1 and ttyUSB5

In each case the FEE64 successfully completed reboot c. 5 minutes later

Attachment 1 - FEE64 temperatures illustrating (we assume) a faulty PSU temperature sensor for aida07

Attachment 2 - FEE64 temperatures following replacement of aida07

Attachment 3-5 - 1.*.W waveforms for aida01 - aida03 - LED settings for aida02 incorrect, aida01 adaptor PCB 
incorrectly aligned

Attachment 6-7 - 1.*.W waveforms for aida02 and aida04

Attachment 8-9 - aida01 - aida04 1.8.L spectra full range and expanded scale
                          pulser peak width c. 15-20 channels FWHM

Attachment 10-12 - good events stats for all FEE64s and all statistics for aida01 and aida05
                   Note aida01 - aida04 show rates expected, all other FEE64s show very rates due to noise
                   aida01 - aida04 adaptor PCB are well grounded to FEE64 copper mezzanine/cooling plate, the other 
FEE64s are not

Attachment 13-14 - aida01 - aida04 rate spectra before and after correcting alignment of aida01 adaptor PCB

Attachment 15 - aida01 - aida04 1.8.L spectra, expanded scale

Attachment 16 - illustrates high frequency noise (period 5 samples = 100ns) for aida01 which is not observed for 
aida02 - aida03
                subsequently determined that this is not due to a possible adaptor PCB fault by changing the adaptor 
PCB
                Note that with bias turned on this noise did appear when Bias was on but all the other groudning
connectors for aida05-aida12
were not in effect.

Attachment 17-19 - PuTTY connection to CAEN 1419ET 4ch high voltage supply illustrating PuTTY, N1419ET configuration 
and leakage current with 100V applied to adaptor PCBs (no input cabling or DSSSD connected)

Note the CAEN N1419ET appears as a 'USB ACM' device and we connect using /dev/ttyACM<n>.