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Re: BCAL Threshold -- Input Needed



Matt,

Better late than never(?).

Matthew Shepherd wrote, way back in mid-July:
> Do we agree that this seems reasonable?  One might hope that signal 
> processing in the FADC could suppress some of the 1 PE pulses.  This 
> would effectively lower the 1 PE rate and allow a lower threshold.
I would also hope that there is some suppression. You are assuming the 
behavior of an integrating ADC in your estimate (conservatism, see your 
words below). The flash gives much more information. Another way of 
asking the question is whether the FADC can tell the difference between 
8 randomly spaced single pe pulses in a 100 ns window from a real energy 
deposition that results in 8 pe's. It should be able to make the 
discrimination at the 80 to 90% level or so, I would think. And if it 
can, the effective threshold can be lower, as you point out.
>   However, I'm sure overlooking things like electronics noise in this 
> estimate, make the estimate somewhat optimistic.  As I said we would 
> like to get as close as reasonable.
>
  -- Mark