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

[Reinhard Schumacher]

Hello Barry,

	Thanks for the quick response.  We agree with all your formatting and 
wording suggestions and will include them in the next draft.
	The normalization question gets a paragraph of discussion starting on 
line 206, and we mention an upcoming paper on the cross sections on line 
66.  There is no one-to-one kinematic link between photon flux and the 
Sigma pi line shapes because we are reconstructing a 3-body final state 
for each event.  A "wiggle" in the photon flux does not make a "wiggle" 
in the line shapes.  Furthermore, the line shapes we present ARE 
normalized, given in micorbarns per GeV.  Thus, we should be well 
insulated from variations in photon flux.

Sincerely,
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 12/15/2012 09:55 AM, Barry Ritchie wrote:
> Nice work. Only a few comments/suggestions.
>
> If intended for the Physical Review family of journals, only the leading word of a title, subsection heading, etc. is capitalized (e.g., "A. Initial selection of particles", etc.).
>
> When momentum resolution is mentioned on line 90, I would suggest saying "Momentum resolution $\frac{Delta p}{p}$ was..." just to be clear what is meant.
>
> Please reference the tagger paper since the CLAS NIM article referenced does not describe the tagger.
>
> Table I title: I would suggest "The number of events remaining after each selection cut  (in thousands).
>
> Figure 4 caption: I would say "Difference in particle time-of-flight $\DELTA$TOF..."
>
> Since you are interested particularly in lineshapes, should we not provide some statement/indication that the photon flux in the energy range subtended by the production energies is reasonably smooth/flat/understood? Ugly variations bin-to-bin in photon flux (see Figure 1) would distort the lineshapes. I'm not saying we need a figure showing the flux (though that wouldn't hurt) but this is the key point of the paper and we don't say anything about smooth/understood tagger flux behavior for these channels. Particularly for W=2.10 GeV in Figure 20 (others, too, perhaps) it would be nice to know the unexplained bump wasn't an artifact of some funny business with the tagger flux that GFLUX didn't sort out.
>
> Please add U.S. National Science Foundation in acknowledgements for those of us who get support from NSF.
>