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Hi all, I studied a bit more in detail the result of the ratio BR(Bch)/BR(B0) on generic MC. With the new statistics (~220 fb-1) I get total BRBR = 0.013032 +- 0.00109235 B0 BRBR = 0.0133296 +- 0.00181513 Bch BRBR = 0.0128752 +- 0.00137274 ratio = 0.96591 +- 0.167051 Since a possible problem could be due to crossfeed I performed two checks: - fit the ratio adding a cut on the integrated purity (only in the fitted sample, not in the models) - fit the ratio changing the relative statistics NB0/NBch. If there is a strong effect of the crossfeed it should show up with this test. Here the results cut on purity ------------- no cut ratio = 0.96591 +- 0.167051 intpur>.3 ratio = 0.896821 +- 0.161344 intpur>.4 ratio = 0.901798 +- 0.180097 intpur>.5 ratio = 0.941965 +- 0.19304 intpur>.6 ratio = 0.999017 +- 0.227691 intpur>.7 ratio = 1.35907 +- 0.387477 intpur>.8 ratio = 1.37365 +- 0.548486 different relative B0-Bch statistics ------------------------------------ B0 1/5 ratio = 0.692619 +- 0.24179 B0 1/2 ratio = 1.09417 +- 0.291523 B0 4/5 ratio = 0.995098 +- 0.185956 Bch 1/5 ratio = 1.41696 +- 0.361108 Bch 1/2 ratio = 1.16043 +- 0.225162 Bch 4/5 ratio = 1.00219 +- 0.176967 I don't see any problem in these numbers. I should be stressed that the statistics is very limited in order to say that the fit is not biased. I am also running a test, varying the generated ratio but, again, with this statistics we cannot say too much. Daniele