[Halld-tracking-hw] ASIC procurement deadline

[Fernando J. Barbosa]

Hi Curtis,

Ok, that's fair.

Best regards,
Fernando



Curtis A. Meyer wrote:
> Hi Fernando -
>
>   give us a chance to finish the measurements we are doing. The scope 
> traces are a bit
> misleading because both preamps are saturating at different levels. 
> This the new one looks
> smaller because the output is limited by the preamp to be smaller, not 
> necessarily the gain.
> We are collecting data for a configuration where neither is saturating 
> to check.
>
>   We also still have the issue of the amplitudes of the cosmic signal. 
> The "lower peak" for
> the old preamp cannot be noise, unless you believe that there are 
> hundreds of channels of
> noise in the system, we saw about 10, so that does not make sense. 
> There is still an
> inconsistency in the measurements that we are making and we need to 
> understand that.
>
>    How long will it take? I don't have a good answer at the moment. 
> The measurements that
> are most sensitive take 24 to 48 hours per point and we don't know how 
> many points we
> need. That (sadly) adds up fast.
>
>     We need to do the following:
>     - measurement with a tilted chamber with the new (and possibly the 
> old preamp).
>     - complete the efficiency curve with the new preamplifier.
>     - collect enough statistics at an optimal point so that we can 
> track and plot with tracked
>       parameters. This could take up to a week.
>
>     Something is very odd with the new preamplifier on the CDC and we 
> are very uncomfortable
> with it right now.
>
>   - curtis
> On 6/14/10 9:07 PM, Fernando J. Barbosa wrote:
>> Curtis,
>>
>> WOW! That's a lot of exclamations - glad they are not expletives.
>>
>> Look at the results you just placed on your wiki, look at the scope 
>> signals, look at amplitude spectra. What else do you need to be 
>> convinced of the fact that the gains are as expected? There is even a 
>> statement confirming that fact that was just placed on the wiki .You 
>> can verify the ASIC performance using the test setup described in 
>> 1364 if you so desire. I stand by my results!
>>
>> I completely agree that you need to understand the behavior of the 
>> CDC and you will need more time for that - no question about that. 
>> Certainly, I won't start procurements until the CDC and the FDC 
>> groups understand the performance of the detectors with the ASIC.
>>
>> I just need an estimate of the completion date. Is this much to ask, 
>> I ask?
>>
>> Best regards,
>> Fernando
>>
>>
>>
>> Curtis A. Meyer wrote:
>>> Fernando -
>>>
>>>   
>>> NO!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
>>>
>>> We do NOT buy off on the gain being lower yet!!!!!!!!!!!!!!!!!!!!!!!!!!
>>> We are still working on more measurements to understand what is going
>>> on. Please do not jump the  gun on 
>>> this!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
>>> We have to be able to get PHYSICS out of the CDC and we have to
>>> make sure that things are 
>>> right!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
>>>
>>>    Curtis
>>>
>>> On 6/14/10 6:33 PM, Fernando J. Barbosa wrote:
>>>> Hi Curtis and Lubomir,
>>>>
>>>> Now that we all agree that the gain on the new preamp is lower than 
>>>> the on the old one, I would appreciate if you could provide me with 
>>>> an estimate to complete your studies with the CDC and the FDC with 
>>>> regards to the ASIC and preamp.
>>>>
>>>> May I suggest July 4th for the deadline?
>>>>
>>>> Thanks and best regards,
>>>> Fernando
>>>
>>>
>
>
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