Hi all,
> 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.
I checked this.
Using the generic MC the lepton ID efficiency goes from 60% to 40% with
respect to the cocktail one.
I discovered that this is probably due to a bias in the mes fit with no
cut applied (very low purity<20%). This is an example of mes fits with no
additional cut required, just the request of vcb (top) or vub event
(bottom):
http://www.slac.stanford.edu/~daniele/vub/mesall.eps
Then, I calculated the efficiency with different levels of purity
b->u
http://www.slac.stanford.edu/~daniele/vub/effvublep.eps
b->c
http://www.slac.stanford.edu/~daniele/vub/effvcblep.eps
and the intpur dependence is striking. With a int purity >30% it starts to
be stable.
The ratio (pstar factor) looks always stable, as shown in
http://www.slac.stanford.edu/~daniele/vub/ratio.eps
and then I conclude that we are ok.
Daniele
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