[Clascomment] OPT-IN:Measurements of ep -> e'pi+pi-p' Cross Sections with CLAS at 1.40 GeV < W < 2.0 GeV and 2.0 GeV2 < Q2 < 5.0 GeV2

[Mikhail Osipenko]

Dear Authors of 2pi paper,

Congratulations with conclusion of such a complex analysis.
Few observations:

1) in the text just before Eq.20 you probably need to specify that you set "eff=1" for these "blind" bins in Eq.13.

2) The explanation of Fig.10 is perhaps misleading: as it is written now one may conclude that CLAS acceptance for pi+p(pi-) hadronic system (in CM) is 100%. I may only guess that Fig.10 actually shows the effect of "blind" bins inside fiducial cuts (bins outside fiducial cuts are also "blind" according your current definition i.e. the number of reconstructed MC events =0). Please could you explain it better in the text/caption?

3) The increase of the ratio of model resonance contribution to the data is very impressive and, I believe, is opposite to what observed in the inclusive cross section. Given the low W-values only few channels are allowed/significant in the resonance region. If I am correct, your observation, indirectly, suggests that in single-pion electroproduction the ratio (resonance/total) has opposite Q2-behaviour with respect to two-pion electroproduction. Is it true? Why this difference?

Best Regards,
                Mikhail.