[d2n-analysis-talk] Beta vs. Track-x, RF time

[Brad Sawatzky]

On Wed, 26 May 2010, David Flay wrote:

> Thanks -- I have been working on something similar to this -- I
> plotted each paddle's time average subject to a cut on the paddle's
> central region in the S2m plane -- as best as I could get it -- I was
> trying to get a region of the paddle that had no overlap, and make
> sure those timing peaks were the same.  This would've been the basis
> of my talk tomorrow.

I'm not sure what is learned from cutting on the middle of a single
paddle.  Perhaps some convolution of intrinsic resolution and amplitude
dependent ToF walk...

Move your tracking cut to overlap the boundary between two paddles.
That will enhance the "two-paddle" events that you need to do the
calibration.

> I'm gonna take a closer look at what you've mentioned, as my
> central-region cut theory breaks down pretty quickly -- I have code
> to create 'virtual paddles' to look at the overlap; but maybe it's
> better/easier to implement the cuts you mentioned -- looking at events
> that fire neighboring paddles -- I was thinking requiring both TDCs to
> fire, as opposed to a geometrical cut, as the geometrical cut doesn't
> necessarily require both paddles to fire.

You should do both to get the best sample.

-- 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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