Date: Tue, 04 Nov 2003 18:26:06 -0600
From: Tony Liss <tml@uiuc.edu>
To: Kenneth Bloom <bloom@fnal.gov>, tecchio@umich.edu
Subject: Branching fractions

Dear Ken and Monica,

    I have finally gone back to your revised note, as Ken asked me to do 
some time ago.  I'm sorry it took me so long.  I think it looks OK now - 
you'll be happy to know.  All the factors look right.  It all comes down 
to how you measure the various epsilon factors - you have to make sure 
that's done in a consistent way with your definitions of the B and beta 
factors.  But you know that.

    One thing that would be good for presentation purposes is to define 
a couple of test models, the charged higgs is one but I think there's 
little phase space left for that in top decays, and do the caculation 
explicitly for them, avoiding the assumption that the acceptance for X 
is the same as hadronic W.  You might even just show how the limits vary 
as you change that assumption, without a specific model.  What happens 
if the X acceptance is only half the hadronic W, for example.  Or if X 
goes to jets X% of the time and leptons (1-X)%.  It's arbitrary, but 
will give people a feeling for how much sensitivity there is to various 
assumptions.

    Cheers,  Tony