[d2n-analysis-talk] d2n PRL Response

[posik at jlab.org]

Hi all,

I just wanted to let you know that we have received a response from the
PRL referees (see below). Overall, it seems that our paper was pretty well
received. Referee B has a few comments that we will now begin working on
addressing, and I will send our answers to the d2n list.

Please feel free to send any comments that you may have.

Thank You,
Matt


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Report of Referee A -- LR14295/Posik
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This is well written manuscript reporting on interesting results. I
recommend that it be accepted for publication.

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Report of Referee B -- LR14295/Posik
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The authors present a measurement of the polarized structure function
g_2 from a transversely polarized helium-3 target with unprecedented
statistical accuracy, the determination of the twist-3 matrix element
d_2^n for the neutron from these data and the determination of the
twist-4 matrix element f_2^n from these data and other additional
information. These results are an important step for a detailed
understanding of the nucleon’s structure and are in my opinion worth
to be published in PRL.

The paper is very well written and I have only two major points of
criticism:

1) In my view the presentation of the results of the extraction of the
twist-4 matrix element f_2^n and of the color forces should be
extended. Given the fact that about half of the introduction deals
with this topic and that the title promises information about color
forces, it is not sufficient to tell the reader that the results are
presented in Table II and then let him draw the conclusions himself.
The results should be compared at least to those presented in Ref.
[17]. The information should be given, why the new central value f_2^n
= 0.073 \pm 0.040 (at Q^2 = 4.3 GeV^2) differs substantially from the
previous value of 0.034 \pm 0.043. Is it mainly due to the change of
d_2^n from the previous value d_2^n = 0.0079 \pm 0.0048 down to the
new value d_2^n = -0.00035 \pm 0.00108 or due to new extracted values
for the other quantities entering the analysis? The contents of the
last two sentences of the paper should not only appear in the summary
but should be mentioned before in an extended discussion of the
results presented in Table II.

2) Only experts that are familiar with the JLAB experiments are able
to relate the acronyms for the various experiments given in the
legends of Fig. 1 and Fig. 2 to the references in the captions.

In detail: In Fig. 1 five experiments appear in the legend, namely
E142, E155, E01-012 (Resonance), E99-117, and E97-103, and in the
caption references [24, 54, 55, 57, 58] are listed.

Ref. [54] can be related to [E142] and Ref. [58] to [E01-012], but
Ref. [57] refers to [E154] and not to [E155] and from the given
information it is open, which of the two references [24] and [55]
refers to E99-117 and E97-103. Similarly the relation between the
three acronyms that appear in Fig. 2 and the references [23, 24, 58,
59, 62] is unclear. Both [23] and [59] refer to [E155] and not to
[E155x].

The captions should be extended somewhat to clarify the relation
between experiments and reference numbers such that the reader is not
forced to search it himself in INSPIRE.

In addition I have a number of suggestions for corrections and
improvements of the text that the authors may take into account for
the revised version of the paper.

* page 2, right column, end of 2nd paragraph:

Instead of ‘in the first moment of g_1, \Gamma_1.’ I propose to
write ‘in \Gamma_1, the first moment of g_1.’

* page 3, left column, 2nd paragraph, line 5:

blank before ‘(E = ..’ missing (twice)

* page 3, left column, 3rd paragraph, line 3:

Why ‘found’? Shouldn’t it be ‘used’ or ‘presented’?

* page 4, right column, 1st paragraph, lines 6-7:

This sentence needs rephrasing. A ‘geometrical overlap’ of a
counter and a signal cannot form a trigger signal

* page 4, right column, 2nd last line:

Remove period between ‘Eq. 8’ and the subsequent equation (9)

* page 5, left column, 2nd paragraph, lines 4-6:

Add blank before ‘(evaluated..’ (three times)

* page 3, left column, 2nd paragraph, last three lines:

It is unclear, how the statement ‘that is about 3 standard
deviations smaller than that reported by the SLAC E155x experiment’
is related to the number d_2^n = -0.00035 \pm 0.00108 from this
experiment and the number d_2^n = 0.0079 \pm 0.0048 from SLAC E155x.

* Table II: dimension of F_E and F_B and equations (6) and (7):

The authors consistently use the dimension (GeV/c)^2 for Q^2. For
consistency then equations (6) and (7) should contain the proper
factors of hbar and c that are needed to get the correct values and
dimensions of F_E and F_B.

* Ref. [17]:

comma missing after ‘et al.’

* Ref. [19]:

remove ‘et al.’