[Clascomment] OPT-IN:Di erential cross sections and spin density matrix elements for the reaction gamma p --> phi p

[Reinhard Schumacher]

                                                      5-7-13
Hello Biplab and Curtis, 

I've read your draft of "Differential cross sections and SDME for the
phi reaction".  It is well written and informative. I have a few
comments and a brief list of typo/grammar corrections.  

The main qualm I have about the analysis is the possible connection
between the ghost of the Lambda(1520), seen in Fig. 5, and the most
dramatic feature of the cross sections in the vicinity of 2.1 GeV, as
seen in Figs 13 and 14.  After one read-through, I did not come away
convinced that the unexplained bump in the cross section is not
related to background.  Can you show a figure in which you
intentionally let some of the L(1520) bleed in, to show to what extent
it is correlated with the bump?

This issue comes up again on page 26 where you say, near the bottom,
that the deviation of B from the typical value is "possibly due to
effects from the L(1520)."  It seems like you are a position to say
more than a guess if you intentionally include some of the background
state. 


page 1 line 1: "electro-"

page 1 line 5: "on-shell"

page 2 line 1: "...while THESE data..." not clear which data you are
referring to; the old or the new?

page 8, col 2, para 2, last line minus one: remove "OVER"

page 8, col 2, para 3: ARE --> IS (singular).  Also, you have written
a lot of the analysis section in present tense.  I think these sorts
of discussion "read better" in past tense.  It is a matter of taste,
of course, but consider casting the discussion in past tense.

page 8, col2, para 4, line 11:  it's not so clear what you mean by an
"invalid tagger counter".  Try "non-triggering tagger counter".  

page 8 col 2, para 4, last line: "this feature" sounds odd.  Replace
with "these cases".  

page 9, Eq 15:  I've never seen this equation in Bevington, the
reference.  Where did it really come from?

page 10, between Eq 16c and 17: Try "A classical ensemble in definite
spin eigenstates is given as..."  I think this is what you mean, since
you are drawing the distinction between this and the coherent state of
the previous sentence.  

page 10, after Eq 33: "Kloet et al HAVE shown..."

page 16, Fig 12:  why is this figure done in a different color?
Actually, you could dispense with colors altogether in many figs since
only one series of data is shown.

page 20, Fig 18: Make the caption consistent with the previous figure
captions, e.g. "CLAS 2013" and "CLAS 2000".  Also, "suppressed"
"superseded"

page 20, Fig 19: "CLAS 2013" to be consistent

page 27, line 9:  "INTO"

Ref 29:  cite the 3rd edition of Bevington and Robinson, 2003.  As
noted above, it's not clear that this is the correct book for the
point you are making in the text.