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Hi Urs, sorry for this short response but I have to leave in 5 min.... So concerning the 1/mb3 errors - these errors are supposed to cover the fact that we use 1/mb3 expansions for mb(lmabda) and l1 but ignor the other 1/mb3 operators (e.g fix them to zero). Therefore, the extracted values Lmabda(1/mb3) and l1(1/mb3) have errors that stem from the above mentioned procedure. When you break them down by one order e.g. Lambda(1/mb3) -> Lambda(1/mb2) one has to include the 1/mb3 uncertainties also in Lambda(1/mb2) because the starting point was the extraction at O(1/mb3) - right? Therefore, the used set of Lambda(1/mb2) and l1(1/mb2) obtained from the 1/mb3 CLEO OPE interpretation should also have (1/mb3) uncertanties - in fact they do, because the ~100 MeV theory error on Lambda(1/mb3) get propagated into your Vub theory error - right? On Wed, 24 Sep 2003, Urs Langenegger wrote: > > Hoi Oliver, > > > Another important issue Ed completely ignores , is the fact, that the OPE > > parameters Lambda and l1 have rather large uncertainties due to the > > unknown 1/mb3 corrections. > > I am not sure about this point any more. As all this (SF relation > between b->sg and b->ulnu) is leading order in mB only, we explicitly > remove higher-order terms to be "as consistent as possible" (though we > are not really, we need the 1/m^2 terms, not only the 1/m terms, as > lone only comes in at 1/m^2). But this might imply that subleading > corrections could be expected to contribute and then we are back at > the higher corrections... > > For all the rest we agree, I think. FWIW, I believe that the error > quoted by Ed is only the statistical, and does not include the > systematics (which are smaller for the measured <E_g>. > > Cheers, > --U. > > >