sPHENIX is a new detector at RHIC.

[David Morrison <morrison AT bnl.gov>]

Dear collaborators,

At today's general meeting, I described the plan to update
sPH-cQCD-2017-002 in response to ALD Berndt Mueller's comments to the
document we sent him.  A good point was made during the meeting that it
would be good to circulate those comments to the whole collaboration.

Here they are.

Cheers,
Dave

-------- Forwarded Message --------
Thank you again for transmitting the sPHENIX note sPH-cQCD-2017-002
entitled "Medium-Energy Nuclear Physics Measurements Utilizing the
sPHENIX Barrel Detector”. I especially want to thank Christine and Nils
for leading the effort that produced this document which contains an
impressive treasure trove of information about cold QCD measurement
possible with sPHENIX.

As you know, I am not only concerned about the substance of the
measurements enabled by sPHENIX, but also about the reception of the
document by the Medium Energy Physics Program Director at DOE/NP. I
believe that from this standpoint, the document could be significantly
improved.  I will be glad to talk about the possible improvements with
you, or directly with Nils and Christine, in more detail but would like
to give you some advance indications.
First, I believe that the document is somewhat poorly structured. There
is no high level executive summary, and each section is lacking a brief
abstract ideally up front of the impact of the described measurements.
As an example, such a summary of section 2 could read:
“Measurements of longitudinal double spin asymmetries in p+p will
improve the statistics of relevant observables (pion and inclusive jet
A_LL) by a factor 4 (?) and allow for a significant (can this be
quantified?) increase in the precision of gluon polarization measurement
in the region 0.05 < x < 0.4. By performing the first measurement of
gluon helicity in the “golden” photon+jet channel, sPHENIX will also
provide a crucial systematic test of gluon helicity determination in p+p
collisions."

Second, the section Introduction contains a statement of the relevant
parts of the sPHENIX run plan. This deserves its own section, but should
not be the introductory section. I don’t want to tell you what exactly
the Introduction should contain, but it needs to address: That the
original science case for sPHENIX had no cold QCD component and why;
what has changed and why; what the overall impact of the cold QCD
measurements that will be possible with sPHENIX is; etc.

If the introduction is written in this manner, you may not need an
Executive Summary, but you may want to have it anyway, so that it can be
used as a brief stand-alone statement.

These changes will add approximately 1 page to the document, but they
will make it much more readable.

-- 
David Morrison  Brookhaven National Laboratory  phone: 631-344-5840
                Physics Department, Bldg 510 C    fax: 631-344-3253
                          Upton, NY 11973-5000  email: dave AT bnl.gov