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Hi all,

 I tried to run the using the generic MC as a b->clnu model instead of the
mixture generic-cocktail. This is the result

 BRBR :0.0144+-0.0036  (it was BRBR :0.0154+-0.0031)

 The error is bigger since the error due the MC statistics is larger. The
difference between the two results (here I am forgetting about the
correlations, the generic MC is 1/3 of the mixture) is:

 D(BRBR) = 0.0010 +- 0.0018

 then the two results are compatible.


 If I add the crossfeed mc to the generic MC I get


 BRBR :0.0155+-0.0036


 Repeating the usual breakdown


 electrons:

 BRBR :0.0139+-0.0049


 muons:

 RBR :0.0198+-0.0057


 B0:

 BRBR :0.0039+-0.0061


 Bch:

 BRBR :0.0260+-0.0050


 For sure the crossfeed does not explain the difference between B0-Bch.



 I also checked the efficiency on the vub generic MC with respect to the
vub-cocktail we are actually using.


 I got


 Eps_u(B0) = 0.368 +- 0.035

 Eps_u(Bch) = 0.312 +- 0.030


 while with the cocktail we had

 Eps_u(B0) = 0.435 +- 0.022

 Eps_u(Bch) = 0.350 +- 0.018


 The difference is

 D(Eps_u,B0) = 0.067 +- 0.041

 D(Eps_u,B0) = 0.038 +- 0.035


 The efficiencies are different. In priciple we should use the ones on
the vub generic MC. This should move up our result of ~12%. I will try to
understand which is the reason of this difference (we already knew that
cocktail and generic MC are different only in the efficiencies).


 Daniele