[Clascomment] comments on The Beam-Target E asymmetry for vec gamma vec n -> pi- p in the Nâ resonance region

[Dr. A.M. Sandorfi]

...touch\'e


On 3/15/17, 4:33 PM, "Barry Ritchie" <Barry.Ritchie at asu.edu> wrote:

> Thanks for the quick response. I think there was a typo in the sentence you
> provided on Moeller. The ad hoc committee likely would appreciate a correction
> there. While I could quibble over "disparate", I'm satisfied with the
> responses.  ---BGR
> 
> Professor Barry G. Ritchie
> Department of Physics
> Arizona State University
> Tempe, AZ 85287-1504
>  
> Phone: (480) 965-4707
> Fax: (480) 965-7954
> 
> -----Original Message-----
> From: Dr. A.M. Sandorfi [mailto:sandorfi at jlab.org]
> Sent: Wednesday, March 15, 2017 3:17 PM
> To: Barry Ritchie <Barry.Ritchie at asu.edu>; clasmbr at jlab.org;
> clascomment at jlab.org; carman at jlab.org; dugger at jlab.org; kjoo at phys.uconn.edu;
> deurpam at jlab.org; pcollins at jlab.org; charleshanretty at gmail.com;
> kageya at jlab.org; annalisa.dangelo at roma2.infn.it; daoh at jlab.org;
> jamief at jlab.org; cbass at jlab.org; Peng Peng <pp9e at virginia.edu>
> Subject: Re: comments on The Beam-Target E asymmetry for vec gamma vec n ->
> pi- p in the Nâ resonance region
> 
> Hi Barry,
> Thanks for your comments. Please see embedded responses below.
> Andy
> 
> 
> On 3/15/17, 2:38 PM, "Barry Ritchie" <Barry.Ritchie at asu.edu> wrote:
> 
>> Great to see this coming out. I have the following comments after a
>> quick
>> read-through:
>> 
>> 0. Since Patrick Collins was also supported by ASU during 2016,
>> perhaps Arizona State University, Tempe AZ 85287-1504 should be added
>> to his address superscript.
> ________________
> Patrick began his involvement with this experiment only in 2011, while a
> Catholic U postdoc.
> ________________
> 
> 
>> 
>> 1. Only the first word of the title should be capitalized: "The
>> beam-target asymmetry $E$..."
> ________________
> Well, the Ad Hoc committee suggested capitalizing each major word of the
> title. I scanned recent PRL articles and they in fact are titled in this way.
> ________________
> 
> 
>> 
>> 2. In the second line of the abstract, W should be italicized.
> ________________
> Done
> ________________
> 
> 
>> 
>> 3. On page 2, please cite the tagger NIM article: D. I. Sober et al. Nucl.
>> Instrum. Meth. Phys. Res. A 440, 263-284 (2000).
> ________________
> Done
> ________________
> 
> 
>> 
>> 4. On page 3, please add "with |P_{miss}| \leq 0.1 GeV/c" to the
>> caption of Fig. 2. You should also indicate what uncertainty is
>> represented by the error bar in that figure.
> ________________
> You misunderstand the figure. This is a plot of the mean value of E, averaged
> over all angles and energies, binned as a function of |Pmiss|. Each point
> results from a separate analysis with a different value for |Pmiss|.
> The error bars are statistical and increase at higher |Pmiss| since the
> momentum distribution peaks around 0.06 GeV/c.
> 
> I've added the following sentence to the caption that I hope helps to clarify
> the plot:
> "  The uncertainties are statistical and are smallest near the peak of the
> $|p_{miss}|$ distribution ($\sim$0.06 GeV/c).  "
> ________________
> 
> 
>> 
>> 5. On page 3, second paragraph, there is an extra "the" that should be
>> removed
>> : "reproduces the observed the..."
> ________________
> Done
> ________________
> 
> 
>> 
>> 6. Why is the photon beam polarization uncertainty so large (given as 3.4%)?
>> With Ref. 12, most of this uncertainty likely comes from the Moeller
>> measurement, right? Then that photon beam polarization uncertain seems
>> quite high for a Moeller measurement uncertainty for any reasonable period of
>> time.
>> Is that a typo?
> ________________
> The statistical error on the Moller data was between 1.4 and 1.4%. A larger
> uncertainty comes from the std dev of repeated measurements, which was about
> \pm 0.04, and this corresponds to 3.3 - 3.4% for 82 - 88% electron
> polarization. We suspect this variation comes from non-uniformities in the
> magnetized scattering foil.
> ________________
> 
> 
>> 
>> 7. On page 4, I would suggest substituting "very discordant" perhaps
>> for the words "wildly disparate". At any rate, "disparate" is not
>> really the word you want here.
> ________________
> Well, you know at some point such adjectives are a matter of taste.
> "Discordant" is too musical for me. "Disparate" is "essentially different in
> kind", which I think is not a bad description for curves that look completely
> out of phase.
> ________________
> 
> 
>> 
>> ---BGR
>> 
>> 
>> 
> 
>