* the 1st draft
  http://neutrino.kek.jp/internal/papers/nc1pi0/2004ktpi0_1st.pdf

* the 2nd draft (new)
  http://neutrino.kek.jp/internal/papers/nc1pi0/2004ktpi0.pdf

* Some numbers in the draft have been changed. All the results
  have already reported in the last K2K meeting by Nakayama.

* The 1st and 2nd authors have set according to the decision
  at the collaboration council in the last K2K meeting.

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Q-1) To use NC fraction for the num<->nut or num<->nus analysis, the
     information about angular correlation between parent neutrinos
     and pi0 direction is very important. This should be discussed
     in the paper.

A-1) The pi0 direction may be very useful for the future num<->nut
     or num<->nus analysis if we have large statistics of pi^0. At
     the current SK num<->nut or num<->nus analysis, the information
     is not so important, and we do not use it. Therefore, we don't
     think that we have to discuss the pi0 direction in this paper.

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Q-2) "Pi0 events with only one ring reconstructed due to highly
     asymmetric or small opening angle pi0 decay" should be
     discussed more quantitatively because it is serious background
     for nue appearance search as written in the introduction.

A-2) It's of course serious for nue appearance search, but this
     paper is not a nue appearance search paper. We don't think that
     it is a subject of this paper, but of a future nu_e appearance
     paper.

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Q-3) In Fig 3-(a), it is difficult to think "the observed data
     distribution is reasonably well reproduced by the neutrino
     Monte Carlo simulation". At least, some explanation are needed
     for the discrepancy in the 200-300 MeV bin.

A-3) Yes, your comment is correct. We should not give a comment of
     "The observed data distribution is reasonably reproduced by the
     neutrino MC ..." at this point. We removed this sentence.
     We make a comment at Figure 4 as you can see at the bottom part
     of the page 5, "The measured distribution is in reasonably good
     agreement on the Monte Carlo estimation.".
     In Fig 4, the difference in this momentum bin between data and
     MC is below 2-sigma if the systematic uncertainty is correctly
     taken care of. We don't think that we have to comment of this
     small discrepancy.

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Q-4) In this paper we are quoting a ratio of two numbers of events
     in 25t of water :
        A/NC events with 1 pi0
        B/CC events
     My concern is that the mean neutrino energy corresponding to
     population A might be different that the one (1.3 GeV?)
     corresponding to  population B. In that case, it would be
     necessary to quote the corresponding mean energy of population
     A (from MC?)

A-4) We added the following sentence in page 6 :
     "By using the CC enriched sample as a normalization, the
     uncertainty of the neutrino energy spectrum~\cite{K2K osc
     paper} is almost canceled in the measurement since the expected
     mean neutrino energy of the CC sample, 1.45\,GeV, is almost
     same as that of the pi0 sample, 1.50\,GeV."

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  The pi0 paper committee would like to
  thank you for sending your comments.