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Hi, I have been investigating the use of deltam, defined as the difference between the mass of the hadronic recoil system and the mass of the same system subtracted of the pion with charge opposite to the lepton. The data-MC comparison of the deltaM variable for B0 events is shown in http://www.slac.stanford.edu/~rfaccini/phys/vub/deltam/comparison7deltamallcuts.ps The D* signal is clearly present and the agreement is really good in the case of the enriched sample, slightly off in the depleted one: there are slightly less D* in data than in MC. Requiring deltaMx<1.6 the data MC agreement looks like in http://www.slac.stanford.edu/~rfaccini/phys/vub/deltam/comparison7deltamallcuts-lonopi.eps The D* peak has disappeared but the agreement is still reasonable. This was the original reason for not using this cut: it makes no effect in the region of interest. Anyhow I have checked the data-MC agreement requesting deltaM>300 MeV. http://www.slac.stanford.edu/~rfaccini/phys/vub/deltam/comparison7mxhadfitallcuts-highdm.ps to be compared with the original one in http://www.slac.stanford.edu/~rfaccini/phys/vub/deltam/comparison7mxhadfitallcuts.ps The depleted is more and more in agreement between data and MC, while the enriched does not show any breakthrough. Incidentally at the RC meeting Franz was mentioning that the depleted sample was not well reproduced by MC. Unfortunately I cannot reproduce Urs's plot in page 11 of his CM presentation, as you can see in my last link. ciao ric