Hi all,
as a sanity check I performed some studies on the ratio of semileptonic
efficiencies (pstartfact). I used cocktail MC.
These are the pcms distribution once you apply the lepton cut for vub and
vcb events:
http://www.slac.stanford.edu/~daniele/vub/allept/pcmslepvubandvcb.eps
and this is the lepton efficiency
http://www.slac.stanford.edu/~daniele/vub/allept/effpcmslepvubandvcb.eps
This plot is very nice and encouraging since, as you see, the
efficiencyies are identical once you take the full spectrum and the value
is ~60% that makes a lot of sense.
A pstarfactor != 1 is only due to the cut on momentum. As you can see in
http://www.slac.stanford.edu/~daniele/vub/allept/ratioeff.eps
that shows the ratio of the efficiencies
With 1.0 GeV cut we get the famous 1.13 value and the ratio change
dramatically as a function of the cut. This shape is perfectly compatible
with the value calculated by the fit
http://www.slac.stanford.edu/~daniele/vub/newscans/all/lastpcmsdataleptonPCutpstarfact.eps
Then I conclude that everything is understood and under control in these
plots.
The only suspicious number in the fit is the total number of vub/vcb
events (but it does not seem to affect the ratio calculation). I am
checking it.
Daniele
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