[d2n-analysis-talk] mwdc 4-pass t0

[Brad Sawatzky]

On Wed, 05 May 2010, posik at jlab.org wrote:

>  So I adjusted the t0 for each plane in the mwdc. I then checked the
> residuals for each plane. Before the calibration the residual sigma for
> all planes was between ~600-800 um and now they take on values of
> ~200-300 um. Some planes are better than others. Below I show a plot of
> the v3p planes t0's and residuals before and after the t0 adjustment.

That looks a lot better.

>   To get an idea of where we are compared to transversity, I talked to Xin
> and for his elastic runs he had a resolution of 180-200 um and for
> production run he had 200-250um. So we differ only by ~50um.
> 
> I am wondering if it is worth doing the calibration wire by wire for the
> t0,wire offsets drift distance to drift time conversion?

I guess the answer to that is given by how this resolution impacts the
momentum resolution (since we will use that to slice the BigBite data up
into bins).  Any idea?

-- 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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