Dear Colleagues,
you can find a draft of the conference paper (clearly too long for PRL) in cvs as BAD582.
Clearly we need time tomorrow to discuss this. Can we keep the ISL meeting short and
discuss this right afterwards.
As you will see, at present
- figures are missing (see blow for suggestions)
- tables need to be updated , since the final numbers were not available to me in time
- results and errors on BR and |Vub| need to be evaluated and checked.
- the reference file is copied from BAD540, and thus needs to be thinned out.
- I have not emphasized the B0 and B+ subsamples, they are of course interesting,
but may divert from the core of the paper. I would not add this to the PRL!
On th4e other hand, we may want to show this at conferences and thus we need to
get this approved by the collaboration.
Also, there are lots of numbers that need to be filled in and cross-checked:
efficiencies and errors, number of events, signal/background, etc. I consider these
sensible additions to the purely descriptive event selection. Some of them are needed for the
evaluation of the systematic errors.
Apart from this, I have difficulty with the definition and use of the efficiencies,
eps(mX) should the fraction of events below the cut in Mx (since we are using
the reconstructed mass rather than the generated hadron mass, there is a small
difference in this number for electrons and muons, but for all other subsamples,
this number should be the same. It is important to quote this number, because it
depends both on the cut and the theoretical model for the mass distribution.
Likewise eps(sel) should be the efficiency for detecting events below the cut in Mx.
It should include the hadronization effects (event though there is some effect of hadronization
on the high mass states).
We measure Nu, correct for eps(sel) to get back the produced number of events below the cut,
and then correct for the fraction above the cut.
If we can clarify this and adopt this approach, then things are more transparent.
Urs suggested that we add to table 1 for the full sample, the fits for different MX cuts,
for instance 1.4 and 1.7 GeV/c2 in addition to 1.55 GeV/c2. I like the idea.
So far for now, "see" you tomorrow,
Vera
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Vera G. Luth Phone: 650 926 2702
SLAC MS 95 Fax: 650 926 2657
P.O. Box 20450
Stanford, CA 94309 e-mail: [log in to unmask]
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