[Bteam] experiment on Compton background and conclusions

[Jay Benesch]

There are four elogs in the BTLOG showing the data taken Sunday 
afternoon and the conclusions I've tentatively drawn from them.
The Optim plots in one didn't get copied correctly by dtlite.  Sorry.

Bottom line is that I can qualitatively reproduce the data in Optim if I 
set alphaX at one standard error below the central value in elog
http://opweb.acc.jlab.org/CSUEApps/elog02/elog_item.php?elog_id=1519083 
i.e. at -15.16 vs -30.16.

The harp traces indicate that the quad scan started near the minima for 
both planes.  I adjusted the values to get a few before the minima and 
drop one from the end of the sequence.  Number of tracrs increases from 
ten to twelve.  We can ask for 40 minutes Monday to take another set of 
traces for use Tuesday in final tuning or just accept the empirical 
numbers subject to checking size at 1H04A and 1H04B.

Jay