Update in tt xsection measurement using JLIP in p14

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Update in tt x-section measurement using JLIP in
p14
S?bastien Greder (IReS Strasbourg)
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Analysis
- First pass this week-end to get event tagging
probabilities for each wjets (Wbb, WbbJ,
W(cc), ...) backgrounds and ttbar. - results
look somehow ok but there were issues concerning
Wj found bug used top_trigger v00.20.02
which has a level 1 bug with EM/Jet trigger.
gt moved to v00.20.03. Ptag(Wj bugged) 0.2566
/- 0.0060 Ptag(Wj ok) 0.3097 /-
0.0072
ltPtag(event)gt Sum evt Ptagweight(event)TriggerW
eight(event)/ltSum evt TriggerWeight(event)gt
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Closer look at Ptag and Trigger weights
Top
Wbb
W(bb)
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Closer look at Ptag and Trigger weights
Wj
Wjjjj
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Conclusion
-Event tagging probabilities look ok -process
might have really different trigger weights
leading thus to different trigger biases
Issues - preselections ?? (ejet seemed to be
ok.., mujet ?) - first of all if we want
to compare ourselves we should should run on
exactly the same filtered samples both in
data and in monte-carlo for both channels.
and then we'll be able to focus into detailed
issues