[esa-t474] ELOG and paper updates

[Yury Kolomensky]

	Hi Mark,

On Nov 9, 2007, at 9:40 AM, Mark Slater wrote:

> Dear All,
>
> After a very successful meeting on Thursday at UCL, we reached a  
> couple of
> conclusions regarding the source of the drifts over long time  
> scales. The
> general results are in my ELOG:
>
> http://pcfj.hep.phy.cam.ac.uk:8080/slater/37

The hypothesis (scale changes coupled to the difference in offsets)  
is reasonable, but do the numbers make sense ? In other words, if you  
plug in the measured offsets, what kind of scale drifts would you  
need to explain the observed relative drifts ?

I am a bit confused what plots you would like to leave in the paper.  
I think some 20 hour plots should still be there, with a proper  
hypothesis/explanation for the cause of the drifts.

> http://pcfj.hep.phy.cam.ac.uk:8080/slater/38
>

Ah ! I think I did ask before which temperatures you used to plot the  
drifts against (see my previous message). I guess you were plotting  
against BPM temperatures ? BPM temperatures only affect the  
frequencies, which you already showed not to be a dominant cause of  
the drifts. The rack temperatures, on the other hand, would affect  
electronic gains (of course). The scale was measured by Maria and  
Erik last summer. See

https://www.hep.ucl.ac.uk/elog//T-474/83

and in particular plots in

http://www.slac.stanford.edu/~chistiak/MccNoOutliers/Amplitude/

Looks like the scale drifts in processors 3,4,5 are O(0.1-0.15%/ 
degree F), or 0.2-0.3%/degree C. Phase drifts seem negligible. Is  
this sufficient to generate observed differences, per your simulation ?


> We also got through English corrections for Sections 1, 2 and most  
> of 3.
> These are now included in CVS with a rough change to the results  
> section
> to represent what we found out.
>
> If I remember correctly, the next meeting about this will be on Monday
> after the ESA meeting. I'm hoping at this meeting to finalise the  
> plots
> that people want to show in the results section, then hopefully one  
> more
> meeting next week at UCL will complete the English corrections.
>

Yes, would be good to have a concrete proposal, e.g. a new paper  
draft, or at least a list of proposed plots. I will try to make the  
meeting, although other priorities (my daughter's birthday party with  
6 tween girls in the house :-o ) may interfere. My apologies in advance.

Yury