Hoi Oliver,
> The maple code from Seven does not take into account the
> correlation between Lambda_bar and lambda_1 which could be large.
>From what I have heard, they are -0.8 (not fit myself).
> Concerning the numbers of the QCD parameters
> Lambda_bar and lambda_1 (or Lambda_bar and a in your case)
> I strongly suggest to use the measurement from CLEO as input.
It depends on what we want to do. If the number is going to be
averaged, it is probably best to use the same error on mb as in that
averaging or provide the appropriate error (which should not be that
difficult...). Else the error will be rescaled for the averaging.
The CLEO value is the only published value, the dominant error is
theoretical and thus not that well defined.
> I do not see any good reason not to use this procedure also
> for the Vub measurement. Any other choice of numbers will have
> to be justified and might face quite a bit of criticism from the
> outside (non-BABAR) physics community.
For the measurement of Vub with the endpoint spectrum BABAR used an
uncertainty of 90 MeV on the kinetic mass of the b quark. This is
consistent with PDG and the CKM workshop. Obviously this is debatable.
Cheers,
--U.
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