[Clascomment] OPT-IN: Measurement of the Sigma Pi Photoproduction Line Shapes Near the Lambda(1405)

[Reinhard Schumacher]

Hello Dan,
	Thank you for your detailed reading of the paper.  We have implemented 
the great majority of your suggestions, including rewriting a few 
sentences that you thought were unclear.  The new paper should be out in 
a few days.  Below we make detailed replies.

Reinhard

___________________________________________________________________
Reinhard Schumacher         Department of Physics, 5000 Forbes Ave.
Carnegie Mellon University, Pittsburgh, PA 15213, U.S.A.
phone: 412-268-5177         web: www-meg.phys.cmu.edu/~schumach
___________________________________________________________________

On 12/21/2012 10:05 AM, Daniel Carman wrote:
> 					December 21, 2012
>
>
> Dear Kei and Reinhard,
>
> I have read through your paper on the L(1405) and include my comments below.
> It has been very interesting to follow this analysis through the various working
> group presentations to see it culminate into this very nice result. It clearly
> demonstrates a lot of hard work on an analysis that was quite tricky. If you
> have any questions, let me know.
>
> My comments are referenced to the paper version dated Dec. 14, 2012 that was
> provided for the CLAS review.
>
>
> 			   Regards,
>
> 				  Daniel
>
> ********************************************************************
> Page 2.
>   - Line 17. I do not know what you mean with the statement "and lead to a deeper understanding
>       of structures that populate this mass region." Are you speaking of disentangling the
>       contributing resonant contributions and non-resonant backgrounds? I think your statement
>       could be made a bit more crisply.
Reworded this clause to be more clear.

>   - Line 23. Use "... theory [4-6] combines chiral ...".
Done.

>   - Line 37. Use "... model [12], the $\Lambda(1405)$ ...".
Done.

>
> Page 3.
>   - Line 44. Use "$S$-wave".
Done.

>
> Page 4.
>   - Line 100. Use "... $K^+$, $p$, and ...".
Done.

>
> Page 5.
>   - Fig. 2. Third column. Use "$\pi^0 \gamma$ (64\%)". (Missing space before B.R.)
Done.

>
> Page 7.
>   - Line 130. Use "... measured momenta, while ...".
Fixed in a different way.

>
> Page 8.
>   - Line 158. Use "... the $\Lambda(1405)$, is below ...".
Done.

>   - Line 161. Use "... $K^+\pi$, where $Y$ ...".
Done.

>
> Figs. 5, 6, 7, 8, 9, 10, 11, 12, 16, 17.
>   - You W labels on the plots do not have units listed. I would recommend that these
>     figures be remade with GeV units explicitly included.
We will either change the figures or the captions to specify the units.

>
> Page 10.
>   - Line 176. Use "... final state, the combination ...".
Done.

>   - Line 179. Use "... $\Lambda \to p \pi^-$.".
Done.

>   - Line 182. Use "... required that MM$^2$ be ...".
Done.

>
> Page 11.
>   - Line 194. Use "... for this run were not ...".
Done.

>
> Page 14.
>   - Line 209. Use "... primary trigger and for the measured $\sim$85\% data acquisition livetime ...".
Done.

>   - Line 212. Use "... of interest and also the ...".
Done.

>   - Line 213. Use "... background reactions in each channel ...".
Done.

>   - Line 216. Use "... fraction ratios, scaled this down ...".
We like this one as it is.

>   - Line 222. Use "... \to K^+ \Sigma^0(1385)$ ...".
Done.

>
> Page 15.
>   - Line 237. Use "$P$-wave".
Done.

>
> Page 16.
>   - Line 259. Use "... relative height of each ...".
fixed in a different way

>
> Page 17.
>   - Fig. 15. Why do you not quote the reduced chi**2? This allows you to make a definitive
>       quantitative comparison.
There are too many fits to summarize with a simple number like this.  We 
dealt with this by adding a point-to-point systematic (outer) error bar 
to each bin, as discussed later in the paper (and clarified as per your 
later comment).  These errors are included in Figs. 16 and 17.

>   - Line 295. Use "... $Y^*(1670)$, which shows ...".
Done.

>
> Page 18.
>   - Line 308. Use "... limited statistics, we sum ...".
Left this as is.

>   - Line 318. Use "... even after several iterations.".
Done.

>   - Line 320. The sentence "An appropriate portion of any fit discrepancy compared to the data ..."
>       makes no sense to me. What are you trying to say here?
>
We rewrote these lines to be more clear.  There is a bin-by-bin 
systematic error that is part of figures 16 and 17 that is supposed to 
indicate how much residual uncertainty in the fits might be ascribed 
specifically to the L(1405) as opposed to the background channels.

> Page 19.
>   - Fig. 16. The magenta points, especially in relationship to the red points, are not easily seen
>       on the figure.
We have improved the figure.

>   - Fig. 16 caption. Line 4. Use "... histogram at the bottom shows the ...".
Done.

>   - Line 333. Use "... distributions at the ...".
Done.

>   - Line 340. Use "... energy $W$, we show ...".
Done.

>   - Line 342. The statement "... we neglect these differences for now." is not clear. What differences
>       are you neglecting? Are you referring to the different cos theta ranges?
Yes.

>
> Page 21.
>   - Line 349. Use "... 2.8~GeV, the mass ...".
Left unchanged.

>   - Line 357. Use "... 1.7~GeV, but we compare ...".
Done.

>
> Page 22.
>   - Line 372. Use "Overall Systematics of the Run".
According to Barry Ritchie, APS rules say only the first word is 
capitalized in APS pubs.

>   - Line 376. Use "... of the intermediate ground state hyperon.".
Done.

>   - Line 377. The systematic assigned for the Delta TOF cut doesn't make sense to me. If you vary the
>       cut on the data, you see a 2-6% change in the yield. That is not a systematic uncertainty source.
>       That is expected because you are changing the integration range. The systematic that you should
>       study instead is the variation in your acceptance-corrected yield when you vary your Delta TOF
>       cut on both data and MC.
Oops, good catch.  Of course we meant to say the "normalized yields"

>   - Line 395. Use "... energy and angle, the $\Sigma \pi$ ...events was fit with a ...".
Done.

>
> Page 23.
>   - Line 414. Use "If there was any ...".
No, we are writing a conditional clause, so it is OK as written

>   - Line 417. Use "Fig. 19(b)".
Done.

>
> Page 25.
>   - Line 444. Use "... can then be obtained ...".
Done.

>   - Eq.(16). Add a comma at the end of this equation.
Done.

>
> Page 26.
>   - First line of page. Use "that is, the interference ...".
Done.

>   - Eq.(19). Add a comma at the end of this equation.
Done.

>   - Eq.(20). Add a comma at the end of this equation.
Done.

>   - Three lines before Eq.(21). Use "... be a "1", let it be the ...".
Done.

>   - Line 467. Use "$S$-wave".
Done.

>
> Page 29.
>   - Line 520. Use "... below the centroid.".
Done.

>   - Line 538. Use "... and one $I=1$ ...".
Done.

>
> Page 31.
>   - Line 557. Use "... of the broad $I=1$ ...".
Done.

>
> Page 33.
>   - Line 594. Use "$P$-wave".
Done.

>   - Line 597. Use "$P$-wave" and "$S$-wave" in this line.
Done.

>   - Line 599. Use "$\Sigma \pi$" to be consistent with usage elsewhere.
Done.

>   - Line 604. Use "... in part by Breit-Wigner $I=1$ amplitudes ...".
Done.

>
> Page 34.
>   - Line 621. Use "... that the choice of one $I=0$ and ...".
Done.

>   - Line 622. Use "... paper led to the best fit among ...".
Done.

>   - Line 623. The sentence "Similar results were obtained using two $I=0$ and one $I=1$ amplitude ..."
>       came as quite a surprise to me, especially presented at the very end. If the fit results using
>       one I=0 and two I=1 amplitudes are essentially the same equivalent (as you seem to be suggesting
>       here) to the fit results using two I=0 and one I=1 amplitude, why have you not presented both
>       fitting solutions in this work? What is confusing me is that you mention that this latter
>       solution "may correspond more closely to current theoretical ideas". This makes this seem even
>       more relevant to present.
This paper, already very long, would get totally out of hand if we 
described more fits.  The cited Nuclear Physics A paper gives 
descriptions of more alternative fits, and we know from private 
discussions that there is some theoretical bias about how this should 
go.  We decided the this paper should only present the best fit we were 
able to get, which may only represent the tip of the iceberg of what 
will be done with this data.

>   - Line 630. Use "$\Sigma \pi$" to be consistent with usage elsewhere.
Done.

>
> References.
>   - You have employed a non-standard format for listing your citations. You have included titles.
>     Sometimes you spell out first names and other times you use initials. You give both a journal
>     reference and a preprint. Sometimes you list last names first. In many instances you do not
>     put proper spacing between abbreviations (e.g. Prog.Part.Nucl.Phys.). Please review this and
>     tidy up.
We are using BibTek in a way we like:  show the titles of the papers so 
the (preprint) reader can see what the papers are about.  We expect that 
the journal editor will switch off the titles when the paper gets 
formally typeset for publication.  It's a simple matter of tweaking the 
instructions to BibTek.

>   - Ref. [15] should use "$\Lambda(1405)$" in the title.
Done.

>   - Ref. [38] should say "Ph.D. thesis".
Done.

>