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Re: Additional data



Hi Fernando,

I forgot to mention one more thing:

The "energy" spectra plotted under "Energy spectra" on the wiki:

I integrate over the signal starting when it is above pedestal and 
stopping when the signal becomes smaller than < pedmean+5*sigma.
If you want I can change that definition.


Cheers,
 	Yves


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On Wed, 18 Jun 2008, Fernando J. Barbosa wrote:

> 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
>