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Hi all, as you probably remember, the three shapes fit came always out with an error 20% lower with respect to the one obtained with background subtracted method. We have never understood completely the reason for this. After the Riccardo's mumblings about this problem and a discussion we had this afternoon, we realized that the likelihood method we were using cannot treat properly the non poissionian error in each Mx bin due to the mes fits (since the likelihood fit does not use that information at all). Then we decided to switch to the chi square method and we obtained compatible results between subtraction and three shapes fits (same error and central value). So, we should use chi square technique instead of the likelihood one in order to get the right error. We propose to switch to the chi square method. The systematics due to the fact that the chisq does not weight properly low statistics bins will be calculated changing the binning. As a consequence, I did not post the results. Let us know if you agree. Here I show you how the new numbers look like. In general the error will be a 25% higher than before. All the disagreements in the various subsamples will be then reduced. All --- BRBR = 0.0164 +- 0.0040(stat) +- 0.0012(MC stat) and this is the plot: http://www.slac.stanford.edu/~daniele/vub/dataplots/datafitresults_nocat.eps Red histo is the total. The blue is the b->clnu. The green one is the "other" component. Here the results dividing the sample in different subsamples: B0: --- BRBR = 0.0032 +- 0.0058(stat) +- 0.0019(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/dataB0fitresults_nocat.eps Bch: ---- BRBR = 0.0266 +- 0.0054(stat) +- 0.0018(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/dataBchfitresults_nocat.eps electrons: ---------- fit problems here. Error < 1 in one of the Mx bins. We are fixing these. muons: ------ BRBR = 0.0249 +- 0.0065(stat) +- 0.0022(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/datamufitresults_nocat.eps run1: ----- BRBR = 0.0094 +- 0.0055(stat) +- 0.0009(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/datarun1fitresults_nocat.eps run2: ----- BRBR = 0.0216 +- 0.0055(stat) +- 0.0014(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/datarun2fitresults_nocat.eps superblock1 (Breco int purity>80%) ---------------------------------- BRBR = 0.0145 +- 0.0071(stat) +- 0.0013(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/datasb1fitresults_nocat.eps superblock2 (Breco 80%>int purity>50%) ---------------------------------- BRBR = 0.0175 +- 0.0057(stat) +- 0.0013(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/datasb2fitresults_nocat.eps superblock3 (int Breco purity<50%, single mode purity>10%) ---------------------------------------------------------- BRBR = 0.0187 +- 0.0076(stat) +- 0.0010(MC stat) http://www.slac.stanford.edu/~daniele/vub/dataplots/datasb3fitresults_nocat.eps The results on the depleted sample can be found at http://www.slac.stanford.edu/~daniele/vub/dataplots/depleted.txt Daniele