[d2n-analysis-talk] retimed TDCs

[Brad Sawatzky]

On Wed, 31 Mar 2010, posik at jlab.org wrote:

>    I followed up on your suggestion to use
> DBB.BBxxxTnn[Ndata.DBB.BBxxxTnn-1] instead of DBB.BBcerTnn[0]. I first
> just plotted TDC 04 from run 2060 with an (DBB.evtypebits&1<<2)==(1<<2)
> cut (t4.png). This is fine, but I then tried to plot the re-timed TDC
> by doing
> 
> "DBB.BBcerT04[Ndata.DBB.BBcerT04-]-DBB.t2[Ndata.DBB.t2-1]+560"
>  with (DBB.evtypebits&1<<2)==(1<<2) cut and I get this (retimed_tdc.png).
> 
> This seems like an odd TDC structure.

Hmm...  It almost looks like there are two copies of the same structure
in the second plot with and amplitude ratio of about 5:1.  Are the two
structures correlated with different "secondary" triggers?  You're
cutting on T2s so they all have that trigger bit set -- I'm wondering if
there's a correlation between the structure and when the event is a T2
and a T1, vs. T2 and T6, etc...

Just a thought.

-- 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
The most exciting phrase to hear in science, the one that heralds new
  discoveries, is not "Eureka!" but "That's funny..."   -- Isaac Asimov