-------- Original Message --------
Subject: Re: COUPP test
Date: Fri, 6 Mar 2009 18:55:11 -0500
From: Philippe Laurens <laurens@exchange.pa.msu.edu>
Reply-To: Philippe Laurens <Laurens@pa.msu.edu>
To: Selcuk Cihangir <selcuk@fnal.gov>
CC: Dean Schamberger <dean@cusb.physics.SUNYSB.EDU>, Dan Edmunds    <edmunds@pa.msu.edu>, Bill Lee <billl@fnal.gov>
References: <49AEEB75.505@fnal.gov> <49AF0B0F.1070409@exchange.pa.msu.edu> <49AF0D30.6060906@fnal.gov>

Hi,

 > The test started at about 9.53 am and ended at 11:28 am, a bit

I studied the L1Cal Track_Ped logfiles over this time period.
The bottom line is that I didn't find any noticeable effect on TT noise.

One easy thing to graph is the average of the noise of all trigger towers
(without TT_Eta=+/-19&20).
The biggest effect I saw was a small decrease during this time period.
It took me a while to realize that the additional noise outside
of this time period is due to the 900Hz zb run.

I then chose 4 points in time,
  1) one a little bit before
  2) one during the first half
  3) one during the second half
  4) one a little after this time period
I used a helper script that can generate a table fit for
excel to plot the difference in noise.  The difference (1-2)
indeed shows a small uniform decrease, (3-4) shows a small increase,
(1-4) and (2-3) show no trend of a difference.

Another helper script can generate a list to track one
(or a few) trigger towers over time, also for simple excel plots.
I even included two HD towers that we have characterized in the
past to have large synchronous noise (and thus could be more
sensitive to perturbations).  Here again I saw nothing to report.

I can put all these plots on the web next week.

Philippe


Selcuk Cihangir wrote:
> Hi Philippe,
> 
> The test started at about 9.53 am and ended at 11:28 am, a bit 
> precisely. First part was an energy scan, sort of, determining the best 
> threshold. So, the best part of the test is from 10:45 till 11:25. The 
> other issue that may complicate the situation is, the pump and the 
> heater of the COUPP turned on and off every 30 or so seconds last 30 min 
> of it. So, unless if it takes a lot of effort, you may want to study the 
> pedestals at this 30 min span, separately, compare them to the ones at 
> 9:45 am and 11:45, for instance. If you see any difference (not 
> expected), we can re-examine the times.
> 
> I hope this clarifies things.
> 
> Selcuk
> ------------------
> Philippe Laurens wrote:
> 
>> Can you be more specific?
>> Am I supposed to compare e.g. 9:45 and 9:55?
>>
>> Philippe
>>
>