all is fine with the b2ulnu PRL, one small remaining phrase issue (see
below). I have prepared a new version in

and propose to reply to the ref with something along the lines

  We do indeed lower  (our) experimental systematic error by measuring
  the fraction  Ru. This is mostly  due to lepton  ID (especially muon
  ID) and to better mES fits. We feel a motivation for the measurement
  in terms of Ru is in place.

  The  larger  acceptance  leads  to  a  smaller  extrapolation  error
  (theoretical error).

  We  have  reworded  the  phrase  so  that  the  distinction  between
  experimental and theoretical systematic errors is clear.

Comments, please? 


   ------- start of forwarded message -------
   From: Physical Review Letters <[log in to unmask]>
   To: [log in to unmask]
   Subject: Your_manuscript LG9660 Aubert
   Date: Tue, 18 Nov 2003 20:40:20 +0000 (UT)

   Re: LG9660
       Measurement of the inclusive charmless semileptonic branching
       ratio of B mesons and determination of $|V sub {ub}|$
       by B. Aubert, R. Barate, D. Boutigny, J.-M. Gaillard, et al.

   Dr. U. Langenegger
   SLAC, M/S 95
   P.O. Box 20450
   Stanford, CA 94309

   Dear Dr. Langenegger,

   The above manuscript has been reviewed by our referees.  Acceptance
   of your paper for publication is likely, but we first ask you to
   consider carefully the enclosed comments.

   Please accompany your resubmittal by a  summary of the changes made,
   and a brief response to any recommendations and criticisms.

   Yours sincerely,

   Robert Garisto
   Senior Assistant Editor
   Physical Review Letters
   Email: [log in to unmask]
   Fax: 631-591-4141

   Second Report of Referee A -- LG9660/Aubert

   I have studied the responses of the authors to my 

   original comments, and the
   revised version of the paper.  I am happy that all my comments have been
   addressed , and now recommend that this paper be published in PRL.  I still
   have two small suggestions relating to some of my original comments (same

   3) The phrase in the introduction line 11 still to my mind sounds like a
   claim that  measurement of the ratio R_u in itself leads to smaller
   systematic errors than have  previously been acheived, which is
   incorrect. I would propose rephrasing it along the  lines:
    `The analysis extracts |V_ub| by measuring the fraction of charmless
   semileptonic  decays R_u=... We acheive a higher signal purity and
   acceptance than previous analyses [4], leading to smaller systematic

   6) Significance of the result for the double ratio on page 13.  I suggest
   adding a phrase such as 'consistent with theoretical expectation', to give
   some interpretation, however brief, of this result.

   Second Report of Referee B -- LG9660/Aubert

   The authors have addressed my concerns and have produced a much more
   readable descripton of their important analysis.  It should be published
   as soon as practible.

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