[d2n-analysis-talk] Scintillator Paddle Time Differences

[Brad Sawatzky]

On Tue, 06 Apr 2010, David Flay wrote:

> Attached are a number of plots that plot the time of the Right TDC of one
> paddle minus it's neighbor's Right TDC time.  So, I overlayed paddle 1 -
> paddle 2, 2-3,... for S1 and S2m.  There seems to be very little to no
> difference here -- all histos line up at ~0.  In S1, there a number of
> deviations, which are much more significant than in S2m.

Watch your binning.  Each bin in the plots you sent appears to be 4--5
nsecs wide.  You'll never see what you're trying to see on these histos.
I would start with the raw histos to do this initial paddle-to-paddle
calibration rather than the _c histos (even if you do null out the
coefficients).

I will also admit I don't understand the other spikes at -60 and +60
on the rt_c[0]-rt_c-[1] plot, never mind the multi-spike structure on
the rt_c[4]-rt_c-[5] plot...  The only thing that is that periodic that
we might see here is the 2ns beam structure...  Do you know what the
real units on your x axes are?

-- Brad

-- 
Brad Sawatzky, PhD <brads at jlab.org>  -<>-  Jefferson Lab / Hall C / C111
Ph: 757-269-5947  -<>-  Fax: 757-269-5235  -<>- Pager: brads-page at jlab.org
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