[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

[Viktor Mokeev]

  Dear Michel,
 We will try to incorporate your edits as much as we can and let you knopw on the updated paper.

 Best Regards,
                     Victor

----- Original Message -----
From: "Garcon Michel" <Michel.Garcon at cea.fr>
To: "Viktor Mokeev" <mokeev at jlab.org>
Cc: "clascomment" <clascomment at jlab.org>, "burkert" <burkert at jlab.org>, "Kenneth Hicks" <hicks at ohio.edu>, ioana at jlab.org, "Ivan Bedlinskiy" <bedlinsk at jlab.org>, "bsi" <BSI at depni.sinp.msu.ru>, "Evgeny Isupov" <isupov at jlab.org>, mkunkel at jlab.org
Sent: Wednesday, March 29, 2017 4:57:37 AM
Subject: RE: 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

Dear Viktor,

I agree, Eqs (4-9) do define the angle \phy_{\pi-} unambiguously and in a graph-independent way. It was the statement line 283 which I found graph-dependent. On the other hand, I find all these equations (+ 10-12) "trivial" and cumbersome, that is why I was trying to propose an alternate and shorter description. On Fig. 8a, you might want to indicate "C" either in the lower left or upper right corner of the electron scattering plane, and remove the mention " e scattering plane" which as placed can be mistakenly attributed to plane A.

As for 7 vs 8, my comment arose from the fact that if the reader uses the same (true) reasoning that you use in lines 300-307 for n=3, you get 8-fold sigmas for n=4 (I am just talking about the final state here), whereas it is stated right after that you have 7-fold sigmas. This is just an apparent contradiction which you can avoid with mention of the "mute" variable phi_e (which would also enter if the target, not only the beam, had transverse polarization). Btw, I forgot to mention in Eq. 15 that you omitted superscripts 5 and 7 on the dsigma's.

I grant that those are "picky" details. I do hope that this clarifies my earlier statements and it's alright with me if you choose not to take them into account.

Best regards,
Michel.

_______________
Michel Garçon
Irfu/SPhN                                               
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