[G8b_run] Good News: Tagger Sag and Momentum Corrections

[Volker Crede]

Hi all,

very good news: we have finally obtained very reasonable results from the 
kinematic fitter. The updated pictures in the attachment are similar to 
those Charles sent out on Monday. The typical tagger sag plot (on page 1) 
shows a flat energy dependence after applying Mike's energy correction. 
Also, the pulls look good and the large displacements have disappeared.

We have been quite wrong earlier this week; we entirely underestimated the 
effects of an energy-dependent energy correction and many thanks to Mike 
for asking us to apply his polynomial. Most of the issues Ken raised in 
yesterday's email receive now satisfying answers. The pulls look quite 
reasonable now and compare very well with Mike Williams results for the 
g10 data (see table on page 3). It looks like we have the systematics of 
the g8b data under control. The justification now for not applying pion 
momentum corrections is that we don't observe problems with the measured 
momenta.

Best wishes and talk to you tomorrow in the meeting

    Volker & Chuck

----------------------------------

Volker Crede
Assistant Professor
Florida State University
Department of Physics
206 Keen Building
Tallahassee, FL  32306  USA

Phone: 001 850 644-2423
Fax: 001 850 644-4478
crede at fsu.edu
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