[Clascomment] OPT-IN:Exclusive eta electroproduction at W > 2 GeV with CLAS and Transversity GPDs

[Stepan Stepanyan]

Draft has a lot of room for improvement. 
One general observation - in the abstract, introduction, and comparison with theory statements are made that results can be described by GPD based models reasonably well. However, on page 9, in relation to structure functions and ratio R, statements are made that "leading-order hand-bag approach is not applicable at present values of Q2". So, it is not clear how GPD models can be applicable if handbag approach is not. 

some other comments:
- p1, caption of Fig. 1, the diagram is called "electroproduction amplitude", it is not diagram of amplitude
- p1, l41, "uncharged" replace with "neutral"
- p1,last sentence of the first paragraph is messy, better to have, remove "also" on line 42 and "to combine the results" on lines 42 and 43
- p2, Fig.2 is this really GSIM, looks like this if from CED 
- p2, l5, this was not separate experiment, so better to say "data were obtained in parallel ..."
- p2, the last part of the last paragraph on right column, starting from line 63, should come forward, in the first paragraph of p2
- p2, l29, is it real 17 degree, in the DVCS paper it says 15 degree 
- p3, l6, remove "in the same sector of CLAS"
- p3, l18, some thing missing in front of "background" - "a background", "pion background" ...
- p3, sentence starting on line 59, "Such a wide ..." must be fixed 
- p5, l7, "as the simulation" -> "as from the simulation"
-p6,l18, Fig. 8 is IC-IC, text says 3 combination have been looked at, but the background is quoted only for IC-EC combination, why?
- p6, l25, x and Q2 bins are shown in Tables I-II (not III)
- p6, Table III is not referenced, can be called at line 26
- p6, statements in the last paragraph is incorrect. First of all QED radiation does not include low energy photons only, and this photons are not detected not because of resolution, but most of them go to along the beamline into beam pipe.
- p6, last sentence, what is means "These processes give the largest radiative contribution ...", which processes this statement refers to.
There is a reference to Fig.9, but the first diagram of Fig. 9 is not a radiative process
- p7, l19, "\phi_\eta" has asterisk, why, is this different from \phi_\eta on line 12
- p7, l30, remove one of "around"  
- p9, l25, should be "in Fig 13" 
- p9, l27, remove one of "fitting"
- p9, l64, it is not clear what concussion to make, above on lines 38 and 42 to 44, it seems statement is that hand bag is not applicable, while here explanations are given in handbag language 
- p12, l25, \theta should be CM angle, asterisk can be used to emphasize that this not a lab angle, for example
- p13, overuse of word "obtained" in two sentences after each other, lines 23 and 26.
- p13, l35, this is important statement, it some how should be reflected in abstract