[Clascomment] OPT-IN:Cross sections for the gamma p --> K* + Lambda and K *+ Sigma 0 reactions measured at CLAS

[Volker Burkert]

This is a nice paper and very well written. I have only a few relatively minor comments: 

1) page 1, right column, end of 2nd paragraph make reference to Bonn-Gatchina analysis. 
Since the evidence for new states in the BnGa analysis comes in large parts from CLAS hyperon 
photo-production data I suggest to modify the sentence as follows:  
"We can look for other "missing resonance" states at higher mass, such as those identified in 
the Bonn-Gatchina analysis [11] largely through precise hyperon photo-production data from CLAS, 
by comparing K* photo-production data to model calculations." 

2) page 2, left column, 
middle of 3rd paragraph: refers to CLAS momentum resolution as ~0.1%. 
This should be more like 0.5-1.0%.  

3) page 2, left column, end of section II.  DAQ live time is given as 90%, while on page 6 it is given as 82%.

4) page 11, last paragraph in section VI.  It states that ".. the model without kappa exchange is in better 
agreement with the data ratio." 
If I understand correctly, this statement is to some degree based on Fig. 12 where the ratio of the two CLAS data sets 
taken with the same detector (but from different run groups) is shown with the ratio of cross sections 
from CBELSA on K*0Sigma^+ divided 
by the CLAS K*+Lambda data. For the ratio of CLAS data one can expect at least some of the systematic 
errors to drop out while this is not the case for the CBELSA/CLAS ratio. In their paper (ref. [6]) the CBELSA 
group shows that their Sigma^+ data are systematically above the CLAS Sigma^+ data at more forward angles, so that the 
ratio of total cross sections will also be above the CLAS data ratio. I think we should not plot the ratio of cross sections 
measured in different labs and with different detectors.  If we only compare the models to ratio of CLAS data, 
 the conclusion would be somewhat different, namely that model II may include too strong a 
coupling to the kappa and the data may be consistent with a smaller coupling but not with the complete 
absence of the kappa in the model. 

5) Fig. 10: do not use green color for one of the models, it may not be visible in the b/w printed version. 
Use a dashed black line or (if color is preferred) a dashed blue line.   

6) Fig.12: Do not include the CBELSA/CLAS ratio, it is misleading. Limit the horizontal axis to Eg=3.25GeV,
 and the vertical axis to 1.5 (if CBELSA/CLAS ratio is removed). 

7) a couple typos: 
page6, right column, 1st line after eqn (12):  "to extracted"  => "to extract". 
page 7, right column, line 2: "and Figs. 7 to ?? shows.." => "and Fig. 7 shows..". 


   
This is it for now. 
Volker