ELOG DESPEC

AIDA GELINA BRIKEN nToF CRIB ISOLDE CIRCE nTOFCapture DESPEC DTAS EDI_PSA 179Ta CARME StellarModelling DCF K40

DESPEC

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Tue Nov 19 21:22:06 2019

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19 November

Waiting for 40Ar beam to be delivered for tests.
Objective today is to assess degrader thickness suitable to stop 40Ar in 2nd DSSD layer.
Energy expected at 300 MeV/A, around 1E3-4 beam intensity - to be determined.

Tomorrow fragments could be expected.

DSSD / FEE64 pairing as follows

DSSD3 (most downstream): FEEs 9,10,11,12
DSSD2 (middle): FEEs 5,6,7,8
DSSD1 (most upstream): FEEs 1,2,3,4
+plastic scintillator furthest upstream

New AIDA Google spreadsheet created with leakage current, to monitor them during beamtime. First entry added. Bias attached.
https://docs.google.com/spreadsheets/d/12hgbrywB10hGsKt5uc2HnLfZymh8_uvM6cEASbbqnBE/edit#gid=813167023

DESPEC platform has already been moved. No effect on rates - see attached. FEE1 is missing one channel. FEE9, 10 noisy as expected. See attached.

System wide checks *all OK* except
Master clock failed (normal)
ADC calibration fails on 6 and 12. Recalibrated via FADC Align. All OK now.

MBS transfer OK. See attached.

Good event statistics OK. See attached.

FEE64 temperatures OK. See attached.

Merger and data rate OK. See attached.

Waiting for beam.

20 November

01:07 - Still no beam.

System wide checks OK. 
Stats OK. 
Temps OK. 
MBS OK. 
Merger and data rate OK.

02:35  - Beam is expected soon
Tried enabling writing data to disk. Merger crashed. FEE64 stopped responding to commands.
Reset Merger. FEE64 now respond to commands.
Tried enabling writing to disk again. Merger crashed once more. Reset merger.
Reset Tape Server interface. Now writing to disk.

No data currently being sent to MBS, but operators say they "are adding a new detector". May be normal.

DAQ & Merger going OK. Writing to Nov19/R1

No beam yet.

Temperatures OK
System wide checks OK
Stats OK. See attached.
MBS not working.
Merger and data rate OK. See attached.

~02:48 Beam on. 40Ar. 300 MeV/A, 500 pps. Degrader settings unclear.

03:54 Degrader settings have been changing between 4.5, 1 and 6 ug/cm2
Currently on 6 g/cm2.
AIDA seen through MBS shows no HE on detector 3, and Det 1 and 2 show no counts on positive y (FEE6 and 1). That is not the case from MIDAS.

04:30 The aim of the tests above was to have no 40Ar at all in DSSD3. It does not appear that 6 g/cm2 is sufficient, as we still see events. The reduction between 1 & 2 vs. 3 is about a factor of 2-10 depending on ADC channel. See attached.

~04:30 Moved to 6.2 g/cm2 degrader. See attached.

~04:45 Moved to 5.8 g/cm2. See attached.

~05:09 Moved to 6.4 g/cm2. See attached.

05:31 High energy channel spectra (1.8.H) for all FEE64 w/ 6.4 g/cm2 degrader - See attachments 13 & 14

05:38: Moved to 1.0 g/cm2. See attached. Difference is not huge which may indicate these spectra are misleading, as partly expected. A more detailed analysis will be carried out off line.

06:00: Beam stopped. ~R77. AIDA keeps running background over the day. Beam should restart around 11 pm later today.

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