Rb/Afb LEP II meeting
March 4
Present: Gerald Myatt, Eyal Brodet, Paula Collins,
Guy Wilkinson (by phone)


EB: Report on B asymmetry.
results on statistical error vs choice of kappa.
results on statistical and systematic error vs choice
of Rb.  Good data/MC agreement, and choice of
Rb cut will probably be close to 1 to optimise
systematic error.  WL raised the point that the
robustness to variation of charm background seemed
suprisingly robust.  This should be followed up by
looking at what the LEPI draft gave.  
Eyal showed good data/MC agreement for
the stabiility plots Qf-Qb and Qf+Qb.  GW asked
for the same plots from ARIADNE.
See transparencies of talk.

WL: report on hot very preliminary results
on Rb.  Full machinery has been run through to the end,
with all results comparable in error to Winter 01, but
the central value overall up by about a statistical sigma.
Wolfgang made a detailed analysis of the pulls: see
transparencies of talk.  WL would like to update
to include the systematic errors at different points
and the correlations between statistical errors of different
points.  Pulls look a more unstable than last
time.  This has to be pursued looking in detail at the
b tag plots.  WL pointed out that the LEP I analysis
revealed underestimation of c background: result to be
taken over in our analysis.

Discussion on dovetailing the analyses.  To do:
Wolfgang and Eyal: run through all data and check that
number of events after hadronic selection and a nominal
b tag are equal.  Eyal will investigate switching to a b
tag with three variables (instead of 6).  Note that this
will change the meaning of x, Eyal should compare his
cut points in terms of say purity.

Discussion on time planning: Will be continued with Guy
in short coffee meeting.  Friday 15:00 was proposed.  To
be confirmed.

Short discussion on possible paper layout (see transparencies)