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Hi all, in this plot http://www.slac.stanford.edu/~daniele/vub/mxsystplots.ps I show the fitted ratio of BR's as a function of the Mx cut on DATA. The blinding is applied, the fit to three shapes is on, the reweighting for the B and D decays is not applied. The central value is going to change since the correct trk and neutral smearing on MC (fix from Urs) has to be applied and the files used to train the fit will be updated in order to take into account the correct fraction B0/Bcha. For sure ,these numbers are fine to look at the stability of the fit. GOOD NEWS: this plot looks encouraging. The BRBR variation is of the order +-10%, a factor two less than the theoretical uncertainty due to the Mx cut. From this plot we could extract systematics to take into account possible violation of the duality in that Mx region. Remember that with the three shapes fit we are not cutting on MX but all the events below MxCUT are put together in a single bin and the full Mx region is used to extract the ratio of BR's. Since we are not actually cutting, we could start thinking about extracting the value of BRBR from this whole set of fits. For instance central value = BRBR spread = syst on BRBR due to duality violation. LITTLE BAD NEWS: there is a jump (at 1.58GeV) around our present cut on Mx. I will try to figure out if this is due to a fit instability. Daniele