[Clascomment] OPT-IN: Photoproduction of the f1(1285) Meson

[Daniel Carman]

Dear Reinhard,

I have read through your draft of the paper on the photoproduction of the f1 meson. This
was a very enjoyable read. My understanding of your approach and your analysis in this paper
were greatly aided by seeing your associated presentation at the CLAS Collaboration meeting.
My comments are included below. If you have any questions, let me know.


					        Regards,
						
						Daniel

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Page 1:
 - Abstract:
  - Line 2. Use "... from a proton target ...".
  - Line 7. Use "... or a high-mass $N^*$ state, ...".
 - Line 42. I suggest "This is significant since the results in this current work are
    consistent with an intermediate value."
 - General: You are not consistent with usage of speed of light unit throughout. I suggest
    that you let c=1.

Page 2:
 - Line 110. You should use "... the CLAS apparatus [28] ...". Ref. [28] does not belong after
     the mention of g11a.
 - Line 121. Use "Target temperature and pressure were ...".
 - Line 132. Use "A set of 342 scintillators, 57 per sector, ...".
 - Line 136. Use "... the detector varied from 0.5\% to 1\%.".

Page 3:
 - Line 145. Use "... accumulated data simultaneously for many different ...".
 - Line 3 after Eq.(1). Use "... the measured time-of-flight, ...".
 - Line 2 after Eq.(2). Use "... from the target to ...".
 - Line 3 after Eq.(2). Use "... to the track hypothesis and ...".
 - Line 161. Use "... in the CLAS TOF scintillators ...".
 - Line 177. I do not understand the sentence "We required all three tracks to pass appropriate
     ...". For all charged hadrons that your detect in CLAS, don't you require them to pass
     delta TOF requirements?

Page 4:
 - Line 227. I would actually think that showing the IM(ppi) and IM(pipi) plots would be
    beneficial to this paper.
 - Fig. 2. Why do you quote the W and cos theta bin for (a) and not for (b)?
 - Line 233. Here "W" should be in math mode. Actually you should check through the paper as there
    are several places where you leave W in rm font.
 - Line 236. Use "... and using a quadratic polynomial ..."
 - Line 236. "... over a 100 MeV range." In what variable? 
 - General: You switch back and forth throughout the paper between using $\Theta$ and using $\theta$.
     Pick one and be consistent.
 - General: In several places you use "Cos theta" instead of "cos theta". Please check through the
     paper and make repairs.

Page 5:
 - Line 249. What does "more favorably shaped" mean?
 - Line 262. MeV should be in rm font.
 - Line 304. I suggest "... data for extraction of differential cross sections.".
 - Line 313. Use "... GSIM [33]."
 - General: If you are insistent on using speed of light in your units, I notice that sometimes
     you write c in rm font and other times in math mode. Be consistent in your usage.

Page 6:
 - Fig. 5 caption.
  - Line 3. Use "A strong signal for ...".
  - Line 4. Use "... and a slight hint ...".
  - Line 6. Use "... of a minimum missing ...".
 - Line 337. I suggest "... was generated followed by the subsequent ...".
 - Line 340. Use "... mechanism [34].".

Page 7:
 - Line 358. The construct beginning "Empirical testing [35] ..." is not a proper sentence. Also,
     I cannot understand what you are trying to say here.
 - Line 361. In the final state, put the baryon first in the listing for consistency with your
    usage throughout.
 - Line 4 of Section B. Use "... selection criteria, was ...".
 - Line 370. Why "$N_{raw}$" and not "N_{gen}"? (also in Eq.(5)).

Page 8:
 - Line 397. Use "... cross sections, as ...".
 - Line 415. Use "... event yields, we varied ...".
 - Line 450. Use "systematic uncertainty".
 - Line 458. Use "... for the cross section calculation.".
 - Line 459. Use "... of the photon flux, ...".
 - Line 460. Use "... of the $\eta'$ yield ...".
 - Line 473. Use "... [38], gives an ...".
 - General: What about statistical uncertainties of the acceptance function? Are they properly
     considered?

Page 9:
 - Line 483. Use "... of the six CLAS sectors.".
 - Line 486. Use "... method, we measured ...".
 - Line 491. Use " ... $\eta'$ for the ...".
 - Line 498. Use "... of the generated Monte ...".
 - Line 504. Use "... for a possible systematic ...".
 - Line 512. Use "... on the cross sections ...".
 - Line 525. Use "Prior to presenting ...".
 - Line 533. Use "... to obtain the cross sections.".
 - Line 543. Use "... systematic uncertainty ...".

Page 10:
 - Fig. 2.
   - What are the error bars shown?
   - Do these results agree within the quoted systematics?
   - If they don't, does CLAS contradict itself?

Page 11:
 - Line 549. "Similar agreement was found when comparing cross sections extracted from
    the decay mode $\eta'$ ...". You should provide a reference to this other CLAS measurement.
 - Line 550. Use "... for the differential cross section ...".
 - Line 559. Use "A survey of ...".
 - Line 602. Use "... with the width ...".
 - Line 610. I suggest "... cross section into the $\eta \pi^+ \pi^-$ final state, ...".

Page 12:
 - Line 622. Use "... in the angular coverage.".
 - Line 627. Broken figure reference.
 - Line 629. How were the different branches combined?
 - Line 636. Use "... in the production angle ...".
 - Line 637. Use "... GeV (threshold ...".

Page 13:
 - Line 664. Use "... final states [19],[48], but ...".

Page 14:
 - Line 687. Use "... {\it et al.} [22] ...".
 - Line 693. Open quotations are the wrong type.
 - Line 709. Use " ... Huang {\it et al.} [23,49] (dotted black), ...".
 - Line 723. Use "... perhaps a non- ...".

Page 15:
 - Fig. 11 caption.
  - Line 2. Use "The solid red line ...".
  - Line 3. Use "... for the $f_1(1285)$ ... for the $\eta(1295)$.".
 - Line 737. Use "Also, the results ...".
 - General: Use "(Color online)" not "(color online)".

Page 16:
 - Fig. 12 caption.
  - Line 2. Use "The Kochelev {\it et al.} model prediction [21] ...".
  - Line 3. Use "The model of Domokos {\it et al.} (dashed blue) ...".
  - Line 4. Use "... [23,49] (dotted black) ...".
 - Line 759. Use ".. 0.022. Even ...".
 - Line 762. Notation problem with the Gamma ratio.
 - Line 765. Use "... both the $f_1(1285) ...".
 - Line 769. Notation problem with the Gamma ratio.
 - Line 793. Use "cannot".

Page 17:
 - Line 809.
 - Line 834.
 - Line 835.

Page 18:
 - Table IV caption.
  - Line 1. I suggest "Radiative decay  $f_1(1285) \to \gamma \rho^0$ branching width 
      predictions compared to the CLAS ...".
 - Fig. 13 caption.
  - Line 1. What is $x(1280)$?
  - Line 2. Use "The data is not yet corrected ...".

Page 19:
 - Fig. 14 caption.
  - Line 2. Use "The solid red curves ...".
 - Line 1. Use "We define a slope, ...".
 - Eq.(16). Add a comma after the equation.
 - Line 855. Spurious parenthesis at end of line.
 - Line 873. Use "... due to the finite ...".
 - Line 874. Use ".. and the detector resolution."

Page 20:
 - Fig. 15 caption.
  - Line 3. Use "... subtracting the weighted ...".
 - Line 938. End sentence with a period.

Page 21:
 - Line 989. Be specific with which figures you are referencing.
 - Eq.(20). Equation does not fit properly on the line.

Page 22:
 - Eq.(24). Add a period after the equation.
 - Line 1013. Use "... they are always close to unity.".
 - Line 1036. Use "... emphasizing the $a_0$ peak.".

Page 23:
 - Line 1092. Do not put parentheses about 3/2.
 - Line 1095. Do not put parentheses about 9/2.
 - Line 1110. Use "... strong bands, we proceeded ...".

Page 24:
 - Line 1128. Use "... decay mechanisms.".
 - Line 1144. Use "... decay mechanisms.".
 - Line 1148. Typo on f1 mass.
 - Line 1156. Missing units on Gamma.

Page 25:
 - Line 1211. Do not put parentheses about 3/2.
 
Page 26:
 - Line 1253. Add space before "Final States".
 - Table V caption. Too wide for column.
 - Table V. Values in table overlap.
 - Line 1274. Use ".. differences were included in ...".
 - Table VI caption. Too wide for column.
 - Table VI. Values in table overlap.
 - Is Appendix B necessary? What is the value added?

Page 28:
 - References are not in standard form. You should not include title and if the
   article is published, you should not give also the preprint number. Finally, if
   there are more than 3 authors, use "{\it et al.}".

Page 30:
 - Ref.[60] and ref. [38] are identical.