Hi all, I reproduced the mx scans for electrons and muons separately (new generic MC, n00 production) All: --- ele+mu http://www.slac.stanford.edu/~daniele/vub/lastscan/newmxmxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newmxmxCutdiff.eps ele http://www.slac.stanford.edu/~daniele/vub/lastscan/newelmxmxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newelmxmxCutdiff.eps mu http://www.slac.stanford.edu/~daniele/vub/lastscan/newmumxmxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newmumxmxCutdiff.eps B0: -- ele+mu http://www.slac.stanford.edu/~daniele/vub/lastscan/newmxB0mxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newmxB0mxCutdiff.eps ele http://www.slac.stanford.edu/~daniele/vub/lastscan/newelmxB0mxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newelmxB0mxCutdiff.eps mu http://www.slac.stanford.edu/~daniele/vub/lastscan/newmumxB0mxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newmumxB0mxCutdiff.eps Bch: --- ele+mu http://www.slac.stanford.edu/~daniele/vub/lastscan/newmxBchmxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newmxBchmxCutdiff.eps ele http://www.slac.stanford.edu/~daniele/vub/lastscan/newelmxBchmxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newelmxBchmxCutdiff.eps mu http://www.slac.stanford.edu/~daniele/vub/lastscan/newmumxBchmxCut.eps http://www.slac.stanford.edu/~daniele/vub/lastscan/newmumxBchmxCutdiff.eps The problem is present only in electron fits!!!! I remind you that the lepton spectrum is also bad only for the electrons. Let's figure out what is wrong with electrons. Daniele