Transcript CPC2-CPR2 Assemblies Testing Status (about f***ing time)

CPC2-CPR2 Assemblies
Testing Status
• Charge Amplifiers
– Attempts to make them work
• Best voltage single channel performance
@ 2MHz
• Cluster finding first results
• Planning
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Charge Amps
No success yet
• Spent hours with Steve and Peter on Thursday
– Setup system so hits are clearly visible on voltage channel
analogue output
– Monitor charge channel analogue output
– Some noise due ADC code conversion, can be removed.
– Change in noise patterns with variation of the relative chip
grounds, still no signals
– Still some behaviour to be understood, some explained
• Keep thinking and trying
– Only one channel of one device tested, statistics are low.
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Best Performance @
2MHz
ADC 240
ADC 197
Noise in e- stays similar until signal is half that of the edge.
Gain dependant on position in the array, noise is amplified too.
Slight reduction in noise when cluster finder clocks are off. (No plot sorry)
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Cluster finder tests
Its possible to test cluster
finder!
Although some channels
always flag data for
readout, multiplexer only
visits them once each
cycle.
Its possible to “sneak”
data through from good
channels, if careful with
occupancy.
Noise Peak
Fe55 Peak
Edge
of chip
Junk data is hidden (due
to garbled timestamp)
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Examples
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Examples
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Examples
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Examples
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Accumulated data
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Remove channel
pedestals
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Plans
• One more week of testing with MB4.4s
– Second assembly
– Go fast as possible (commercial driver
limited)
– Sort out charge channels
– Improve some results, lots of data!
• Make way for MB5.0
– Come back high speed testing when driver
chip can be used
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