Hi Kerstin,
> 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.
> 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?
Daniele
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