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Hi all,

 as discussed at the meeting I performed the systematics due to the
exclusive b->ulnu BRs varying separately the pilnu and the rholnu
contributions instead of varying all the exclusive components of the same
relative amount.

 These are the results:

   test                                                BRBR

 BR(B0->pi+lnu) +30% && BR(B+->pi0lnu) +30%           - 1.7%

 BR(B0->pi+lnu) -30% && BR(B+->pi0lnu) -30%           + 2.0%

 BR(B0->rho+lnu) +30% && BR(B+->rho0,omegalnu) +30%   - 0.5%

 BR(B0->rho+lnu) -30% && BR(B+->rho0,omegalnu) -30%   + 0.8%

 BR(B->pilnu) +30% && BR(B->rholnu) +30%              - 2.5%

 BR(B->pilnu) -30% && BR(B->rholnu) -30%              - 2.8%


  as a crosscheck I tried to remove all the remaining exclusive compenent
(not yet observed decay modes)

 BR(B->Xlnu (not pi and rho)  -100%                   - 5.8%


 and it seems to go in the opposite direction but explanes why the
hybrid and the non resonant model give then similar results (something
like a compensation). Quoting this difference as systematics probably
would be too conservative since it implies that we don't use at the
theoretical information about eta, eta' , a1, b1 , f1 lnu decays.


 I propose to quote a simmetric syst uncertainty of 2.6%. Together with
the systematics due to the fit using the pure non resonant model it gives
us a systematics of ~4% that would be conservative.


 Daniele