[Clascomment] OPT-IN:Target and Double Spin Asymmetries of Deeply Virtual Ï0 Production with a Longitudinally Polarized Proton Target and CLAS

[Andrey Kim]

Dear Michel,
Thank you very much for your comments and corrections.
I implemented most of them. A few comments:
eq1: I decided to bar Q2 dependence for consistency. This formula is 
from papers of GK and GGL model and they don't include Q2 there.
l.206: We used simple parameterization of Gm/Ge = mu/(1-Q2/9). I 
included paper from C.F. Perdrisat, V. Punjabi and M. Vanderhaeghen as a 
source for parameterization. Please let me know if you know any source 
that precede their paper.
l.218: I don't like to list range because there are few bins with very 
large systematics due to statistics, and range would be misleading. 
Although the average is misleading too, I prefer the lesser of two 
evils. The reader can see these systematic spikes on the plot as well as 
usual systematic behaviour.

The new draft will be distributed shortly.
Thank you,
Andrey.



On 10/01/2015 07:51 AM, Michel Gar�on wrote:
> Overall, the article reads well and the message is clear. Nice work ! I have some detailed remarks and corrections though:
> Abstract l. 9 : Large VALUES, not amplitudes. The word amplitude is rightly used at the end of the same sentence.
> l. 32: Insert  after тАЬprocesses.тАЭ The sentence
> тАЬThe conventional ETbar = 2HTtilde+ET will be used as well hereafter. These GPDs can be accessedтАж.тАЭ
> with optional reference to M. Burkardt, PRD 72, 094020 (2005).
> Eq. 1: F depends on Q2 as well (evolution)
> l. 76: if I am not mistaken, eqs 2 and 3 are quite general, model independent. They only suppose one photon exchange. Then bar тАЬat the leading twistтАЭ. Same applies to l. 243.
> l. 82: unpolarized structure functions. Bar тАЬspinтАЭ.
> l. 93: [12] only deals with chiral even GPDs and DVCS. It is not the best place to introduce the GGL model  in this context. I would just use ref [17]. Same remark for caption of Fig. 4.
> l. 136: тАЬemittedтАЭ instead of тАЬscatteredтАЭ photons.
> l. 147: тАЬadditionalтАЭ instead of тАЬextraтАЭ
> Fig.1 x-label and line 156: use the same notation for missing mass.
> l. 184 тАЬpolarization dependentтАЭ instead of тАЬasymmetricalтАЭ
> l. 198: тАЬcorresponding beam chargeтАЭ instead of тАЬtotal chargeтАЭ
> l. 206: [15] is not enough to calculate the ep spin asymmetry. It gives the formula, but you need a form factor parameterization to get a number. You should quote also the form factor parameterization which you used.
> l. 209: remove \simeq .
> l. 215: тАЬwere modified from 3sigma to 2.5тАж..тАЭ
> l. 218: IтАЩd rather see a range quoted here: тАЬThe corresponding variations of asymmetries ranged from ?? to ??% in all kinematical binsтАЭ. The average in l. 225, including all sources of bin to bin syst. errors, is fine there.
> l. 249: full stop after тАЬasymmetriesтАЭ and then тАЬThis observable is importantтАжтАЭ
> l. 276: GGL
> l. 293-295:  3 articles missing. the target spin asymmetryтАж.the beam beam asymmetryтАж A moreтАж.
> l. 307: тАЬreal part of the even-odd product тАжтАЭ instead of тАЬreal part of chiral-even and chiral-odd GPDs productтАжтАЭ since the quantities in brackets are not the GPDs themselves.
> l. 308: The overallтАж
> Ref [17]: the second author is J. O. Gonzales Hernandez (hence the GGL).