Hi Daniele,
> > I ran the VirVubFitter jobs on generic MC using the same genMC files for
> > the generic MC and as data (as we said on Friday). This uses the ichep
> > ntuples. You can find the VirVubFitter output in the following directory
> > at SLAC: ~kerstin/scra.
> > Taking the numbers from the results.dat for the fitted numbers of events
> > in the first bin (0..1.55GeV) I find
> > S/N(mxhadfit) = 1.04
> > S/N(mxhad) = 0.98
> > so the difference is a lot smaller than what Roberto saw on data if I
> > remember correctly. Maybe someone could check my numbers to make
> > sure I did not mess it up?
>
> your results show that, as far as the BR measurement is concerned, the fit
> is not useful at all?
> this is true for the mx analysis with a cut at 1.55 GeV. I am not sure it
> is the same for a looser cut. If I compare the two ...fitresults.eps
> files I notice that the "D0/Dc" bin (the second bin in mx) is quite
> different between mxhad and mxhadfit. This should imply that there is more
> background for mxhad if you use loose cuts in mx.
Ok, I understand. Would it be the plan to try to go to a higher mX cut or
would this mean that what we see here might not be the same for mX-q2?
> > Also I computed the moments for the unfolded spectra. Please find the
> > tables in here:
> > http://www.slac.stanford.edu:~/public_html/vubfit/moments_data.pdf
> > The systematics evaluated are the same we had on Friday:
> > statistical (on spectrum and detector matrix), multiplicity category
> > reweighting, B->Xclnu BFs, exclusive D BFs, mb and a from Belle, B->Xulnu
> > BFs (as done for ichep).
> >
> > The first four pages have tables for the uncorrected and the bias
> > corrected moments as obtained on data for mxhad and mxhadfit. Comparing
> > the uncertainties it looks like we see quite larger uncertainties on some
> > of the moments using mxhad. This is coming mostly from the systematics
> > (see the tables where the uncertainties are split up). I tried to figure
> > out where this comes from. First having a little closer look at the error
> > bars on the left plot on page 4 of VR011105.pdf from last Friday you can
> > see that we have larger error bars for mxhad than for mhadfit, so this is
> > consistent.
>
> but do we understand why the error on the subtraction is different?
I think I am not sure what you mean by error on the subtraction. One the
charm background subtraction? But I think you said on Friday that we would
expect to have higher uncertainties on the charm subtraction?
Kerstin
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