[Clascomment] OPT-IN: Induced polarization of Lambda(1116) in kaon electroproduction

[Volker Burkert]

Dear lead authors,

The paper has some very interesting results that will help in the development of 
better models for exclusive kaon production in the nucleon resonance region. 
I have a few comments on the content of the paper:

ABSTRACT: l 21:
 "..provide evidence OF previously unobserved..."

INTRODUCTION:
l 24-25: "The strange quark plays an important role in understanding the strong interaction..".
 The statement needs a reference in support of it. 

l 69:  One could add a sentence "They have been essential in identifying and providing evidence
         for new excited nucleon states in the 1900 MeV mass range, and are now included in 
         the particle data tables (PDG2012). 

l 83:  Reference [36] to Hall A in the references is listed as (CLAS collaboration).  

FORMALISM:
 l 125-129: The sentence is incorrect. Single pseudoscalar meson electroproduction
                   is described by 6 independent parity conserving complex amplitudes 
                   (note photoproduction has 4). The complete characterization  of the
                   production process requires 11 (modulo one overall undetermined phase) 
                   independent measurements (note photoproduction requires 7 independent 
                   measurements) to be fully determined. The table of the 36 response functions
                   show all possible non-zero measurements that can be done, however only
                   11 of them are fully independent. The reference [39] also clearly states that. 

EXPERIMENT: 
 line 433:    It is better to begin the sentence with: "The choice of parameter b=0.3 GeV^-2
                   yielded a ....."

RESULTS and DISCUSSION:
 line 557-558: For consistency with the ranges given in Fig, 9, replace the $\leq$ with < .

 line 610-614: The phrase "came to different conclusions" is too indefinite. The latest edition of
                        PDG2012 and 2013 online live edition shows the state as a *** N(1900)3/2^+, 
                        a results of including the CLAS photoproduction data in coupled channel (BnGa) 
                        as well as single channel (Mart,2012 and Maxwell, 2012) analyses.  

line 631: The N(1900)3/2^+ is no longer a "missing", but an established *** state.  

CONCLUSIONS: 
 line 711: What does the sentence "the first published induced ..results" mean?  Are there other 
                unpublished results? Btw, our paper is also not yet published. Would it be better to delete 
                the "published"?
              
REFERENCES: 
 Change the reference [36] to Hall A collaboration.   

Best regards,
Volker