[d2n-analysis-talk] BB Cerenkov TDC cut

[Brad Sawatzky]

On Thu, 11 Mar 2010, posik at jlab.org wrote:

> So I have been working on the BB cerenkov multi hit TDCs. I first
> tried to do this by running a script that implements the TDC cuts
> though strings ie
> 
>    T->Draw(var,"DBB.BBcerT04<400.0 && "DBB.BBcerT04>150.0")
> 
> Since each TDC can handle 16 hits I wrote some code that loops over
> all 16 hits for a given TDC and then histogramed it. In this case I
> chose to look

You can't loop over 16 hits.  The I believe the DecData class only
stores a maximum of 5 hits to the Tree (arbitrary limit set in the
source code). Also, recall that the DecData class only guarantees valid
data for DBB.BBcerT04[x] for x=(0,Ndata.DBB.BBcerT04).  If
Ndata.DBB.BBcerT04==-1, then DBB.BBcerT04[0] is undefined (may not even
be initialized).

That needs to be fixed before your plots will make sense.

-- Brad

-- 
Brad Sawatzky, PhD <brads at jlab.org>  -<>-  Jefferson Lab / Hall C / C111
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