Re: Additional data

["Fernando J. Barbosa" <barbosa@jlab.org>]

Hi Gerard,

I think Yves is plotting peak amplitudes from the ADC sampled data 
because they are what will determine the dynamic range for the ASIC for 
different particles, track lengths, etc. Of course the amplitude is 
proportional to the charge (~ 15% with 11 ns peaking time) from the 
event in the detector.

Trying to understand the amplitude spectrum in the context of energy 
resolution, and not the dynamic range for the ASIC, is what I was asking 
Yves. In this regard, we would need the plots to show the sum of all the 
samples within the drift time "gate"(~300 ns ?). How is the trigger 
formed, coincidence of straws? Certainly Yves will be able to tell us 
more details.

When I first looked at the plots, it seemed to me that the escape peak 
for Ar was visible, in addition to the 5.9 KeV Fe55 peak. With more 
recent data, I am not sure that is really there.

Regards,
Fernando




Gerard Visser wrote:
> Hi -->
>
>     Gerard
>
> Fernando J. Barbosa wrote:
>> Hi Yves,
>>
>> I would like to take a look at some of your raw ADC data in time for the
>> triggered events. Also, it would be nice if you could provide a diagram
>> of the triggering electronics/detectors and setup. I am particularly
>> interested in the data from the three plots under "what about another
>> straw ..." and the three following plots under "Different-HV".
>>
>> With regards to the energy measurements, I would like to look at plots
>> of the sum of the ADC samples over the drift time of the straw for the
>> same plots I mentioned above for triggered events.
>
> Not that I understand the apparent spectrum here (can you explain 
> it?), but I certainly _thought_ that is exactly what Yves is plotting. 
> Isn't it? "Amplitude" = integral of the pulse ~= integral over a fixed 
> time bracketing the pulse. Pedestal subtracted of course.
>
> Or are you plotting peak height here, Yves? That would probably allow 
> for the strange shape of this curve. (??)
>
>>
>> Thanks,
>> Fernando
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