Hello folks,
we said we wanted to check the value of the ration of the leton selection
efficiencies on generic MC using the ratio
R=#lepton selection/ # generated =epsilon_l * epsilon_t
I did this using the vub+generic and the generic MC for Vcb. I assumed
that all the generic MC has a semileptonic BF of 10.4% [Urs, private
comunication].
Just for reference (bookeeping plays a role in this calculation) here are
the root files I used:
/nfs/farm/babar/AWG7/ISL/tmp/rootfitfiles/lastfiles/sx-allvub.root <- Vub
/nfs/farm/babar/AWG7/ISL/tmp/rootfitfiles/lastfiles/sx-allgeneric.root <-Vcb
and the number of events I assumed to be present before any selection:
nVub=954000 (half B0 and half Bch)
nVcb (B0)= 28263100*0.208
nVcb (Bch)=29580900*0.208
with these numbers I fitted the mes spectrum after lepton selection both
for Vub and Vcb events (nVubl,nVcbl) and then computed
pstarfact = nVubl/nVub/(nVcbl/nVcb)
and got:
total 1.12401+/-0.0495682
The break down among modes is
D0 0.973009 +/- 0.0660305
D*0 1.23887 +/- 0.0823735
Dch 1.3156 +/- 0.169135
D* 1.14361 +/- 0.133126
The agreement could be better, I need to check what happens with the B0,
but this initial test shows better agreement with the cocktail answer
(1.133) than with the naive generic answer (1.332)
ciao
ric
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