Hi,
you'll find results about Mxhad vs Mxhadfit tests, done with CM1, in
1) 1D Mx distribution
2) 2D Mx & q2 distribution
in http://www.slac.stanford.edu/~azzolini/Mxhad-Mxhadfit.txt
cheers
Virginia
On Thu, 20 Jan 2005, Heiko Lacker wrote:
> Hi,
>
> as agreed in our last phone meeting we will have another one tomorrow,
> Friday, 8:00-9:xx (since we had to drop the regular one last Tuesday.)
>
> I will send you the coordinates for the phone conference in time.
>
> I'd like to discuss how we can update asap the (old) results on Run1-2
> for the CKM WS with respect to
>
> 1) New Neubert model
> 2) Variation of the SF models
> 3) Updated numbers from Bauer et al. for mX-q^2
>
> In addition, we should discuss the status concerning the code development
> for
> a) Kinematic Fitter
> b) Partial D* reco
> c) New tag for VirVubFitter?
>
> Cheers,
> Heiko
>
> On Mon, 17 Jan 2005, Heiko Lacker wrote:
>
> > Hi,
> >
> > I try to summarize what we have learnt so far if I got
> > everything correctly (please correct me in case I
> > missed something):
> >
> > mxHad <-> mxHadfit
> > -------------------------------------------------------
> > BRBR Not a big improvement when using mxHadfit
> > concerning statistical errors
> > However, I would guess that this is not
> > any more the case when also considering
> > systematics from b->clnu.
> >
> > Moments Errors on Moments seem to be significantly
> > larger when using mxHad instead of mxHadfit
> >
> > At least concerning the second topic we would like to use
> > a kinematic fitter. How well we are really doing using the
> > VertexTreeFitter is also not known at this stage.
> >
> > My personal point-of-view:
> > In this situation the only reasonable thing to do wrt the
> > CKM workshop is to produce updated numbers for Run1+Run2
> > concerning:
> > 1) using the new Neubert calculation
> > 2) mX-q^2 result using updated numbers from Zoltan and Co.
> >
> > In addition one might try to add:
> > 3) One bin-unfolding for mX
> > 4) Further Tests on the unfolding and calculation of moments.
> >
> > Please give me feedback!
> >
> > Cheers,
> > Heiko
> >
> > On Mon, 17 Jan 2005, Kerstin Tackmann wrote:
> >
> > >
> > > 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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