2006/11/15%20NKS%20meeting

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2006/11/15NKS meeting

• Tohoku University
• Kyo Tsukada

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New NKS at LNS
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Schematic view of DAQ system

• K0daq2
• VME Bit3 620
• read TKO via SMP
• CAMAC CC7700
• receive interrupt
• read scaler
• K0daq1
• VME Bit3 620
• read AMT
• CAMAC CC7700
• receive interrupt

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DAQ performance for normal trigger (run453)
DAQ efficiency is 80 for the beam intensity of
2MHz.
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DAQ performance for normal trigger w/o EV (run430)
K0 K0 L L
w/o EV w EV w/o EV w EV
??? (yield) 3 2 15 10
DAQ performance 60 80 60 80
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DAQ performance for k0daq1 and k0daq2 ( run407,
408)
Trigger condition nIHgt2nOHgt2TAG
k0daq1
k0daq2
DAQ performance of k0daq1 is 10 worse than that
of k0daq2.
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Dead time of k0daq1

• AMT conversion time nhit5usec 25usec
• AMT data structure 2 header data 1 footer
• AMT read out 2usec/word
• Mean estimation
• data at 1 event 80 data
• AMT at 1 event 10
• Conversion 8525 65 usec
• Read out 1002 200 usec
• Total 270 usec
• ? 73_at_1kHz ...
• In fact, 60_at_1kHz
• The long tails exist.
• Please remove the noise on chamber.
• Most easiest way to reduce the dead time is

One more DAQ PC ?
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Event correlation

• I could not find a cause of the incompatibility
  of event correlation between k0daq1 and k0daq2.
• The incompatibility relates to the request rate.
• If the request rate is less than 1kHz, the
  difference is almost less than 10 at about
  1000000 events.
• Maruyama developed analyzer automatically fitting
  the difference.

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Read out