STAR HardProbes PWG

["Mooney, Isaac" <isaac.mooney AT yale.edu>]

Hi Nihar,

Your proceedings lay out STAR’s hard probes program very well. I have some 
comments below, but the majority are just spelling and grammar related, so I 
grouped them together.

Thanks,
Isaac

Spelling/grammar/other small things
10. "aims to investigate"
12. "Amassing a..."
14. "hard probes"
16. "QGP" or "the QGP's"
20. "is compared"
24. "antiquarks"
29. "processes"
30. "to explore the" -> "exploration of the"; "regimes"
32. Remove "constant"
33. "serve as a"
34. "experiment's"
35. "conference in Aschaffenburg..."
37. "phenomena
38. "studied" -> "done"/"accomplished"/...; "direct photon + jet, and 
hadron+jet" -> "jets recoiling from hadrons or direct photons"
40, 41. "are also discussed", "are thoroughly discussed" is repetitive.
42. "for the hard"
44. "experiment"; "comprises several..."
45. "A recent"
47. "for triggering, and for"
50. "Plane"; Problem with singular/plural clash here. Suggest: "The 
Event-Plane Detector (EPD) is composed of two symmetric halves placed at 
both..."
54. "subsystems"
56. "enabling detection of neutral..."
57. Remove "high p_T" since it's at forward eta; funny spacing between "<" 
and "4".
64. Another singular/plural clash here => "correlator (or EEC) helps..."
66. "allows one to measure" or "allows for measurement of"; "in QCD".
69. "using the anti-k_T algorithm in p+p collisions"
72. "angular"
74. Remove "with a"
76. "in the quark-gluon regime"; "\times" is unnecessary
79. "observable"
81. What you said is true, but it omits its use just to remove NP 
contribution from the jet shower/hadronization.
85. "of the parton shower" or "of parton showers"
88 (and throughout): "in Ref. [7]"
89. Move "the" after "pQCD and"
95. "as defined and shown in"
102. "observables"
111. This sentence seems a bit garbled. E.g. "R=0.2 over 0.5 (...) 
coincidence" is not coherent. Maybe: "...reports the comparison (R^0.2/0.5) 
of yields of jets with two different radii (0.2, 0.5) recoiling from 
direct..."
116. "contributes to our understanding of"
119. Remove "On the other hand"
126. This is worded a bit misleadingly. It makes it seem like you're saying 
the baryon/meson ratio in heavy-ion collisions is > 1, which is not what is 
meant. Suggest: "The enhancement of the baryon-to-meson yield ratio in 
heavy-ion collisions compared to pp collisions..."
133. "preference for pion production over proton production"; "on the left of 
Fig..."
135. "200 GeV, for jets with a hard-core selection and radius of 0.3, the 
(p+\bar{p})..."
146. "jets show"
147. "consistent with that from"
149. "A semi-inclusive measurement of recoil jets in coincidence with a 
charged hadron within trigger p_T of...is also presented"
151. "systems" (also 153.)
Fig. 7. "as a function of p_T,jet"
153. Remove "In STAR,"
160. "However"
161. "Besides" -> "In addition"
162. "along with its"; "no significant"
165. "states"; "thermalization"
166. "and sizes"
169. "significantly more"
References: Can you hyperlink the DOIs and arXiv numbers?

Physics/structure/message
36. This is slightly misleading, since the jet mass itself is not presented. 
Rather the CollinearDropped mass is shown (and the groomed mass fraction is 
discussed as well). This is probably too detailed to go into at this point in 
the proceedings, so maybe "jet mass, and jet shape" could just be changed to 
"observables relating to the distribution of momentum and energy within the 
jet" or similar. Although then I would almost suggest just removing "like 
energy-energy...jet shape".
80. It should be mentioned somewhere that the CD measurement uses MultiFold 
since this is a novel and exciting technique.
92. This is a bit vague, and I'm not sure it will come across what DeltaM/M 
actually is. Instead of "the jet mass fraction resulting from the 
CollinearDrop", I would recommend something like "the fraction of the jet 
mass that would be groomed away by SoftDrop"
96. "indicates narrower splits lead to smaller virtuality transfer"
102. "whereas PYTHIA-8 may need further tuning of parameters related to the 
hard process and jet evolution"
124. Is this true? What about 
https://urldefense.com/v3/__https://inspirehep.net/literature/1817734__;!!P4SdNyxKAPE!ChcV1uliU6lAeNEdRDGW4V76xXWQd_bxX5PZ-NydcjecLpTJRRzrdGS6WLlX1KqcwxesBN2TRwyGWfMdHuxoVvoO0mE9hjE$
  ? Maybe you meant to say "at RHIC"? Also, I think there should at least be 
some comment about the physics of this result even if it's as quick as "which 
could potentially be explained by medium response".
136. Again, I think it would be good to have a half-sentence explanation of 
the result, even if we point to the reference for the full story. You do this 
on l. 143 very nicely. Something like "suggesting that at least for high-p_T 
constituents, QGP coalescence does not contribute to the hadronization 
process in a jet."
160. I don't understand why only the suppression in Au+Au collisions is 
highlighted as strong. I would also call the isobar suppression strong at 
high multiplicity.
170. It would be interesting to add a reference to a paper which calculates 
the dissociation temperature of Upsilon so an inference can be made about the 
minimum peak temperature of the QGP at RHIC.
196. I'm not sure what this sentence is intended to mean. Do you mean that 
the results cast doubt on our ability to discern the effect of the initial 
medium configuration on hard probes? Because I don't see how you get that 
from the results. We have a positive jet v2 which seems to suggest the 
opposite. And the J/psi v2 is almost centrality-inclusive and has large 
uncertainties, and even so there may be a hint of a v2 for the TPC EP method. 
And your sentence is a very broad statement not just about STAR data but 
about "heavy-ion collisions" in general, which also seems contradicted by 
other results from the field, e.g. 
https://urldefense.com/v3/__https://arxiv.org/pdf/2307.14097.pdf__;!!P4SdNyxKAPE!ChcV1uliU6lAeNEdRDGW4V76xXWQd_bxX5PZ-NydcjecLpTJRRzrdGS6WLlX1KqcwxesBN2TRwyGWfMdHuxoVvoOW3NxhSU$
 . I also don't understand how we can reconcile that the RAA in isobar and AA 
is only dependent on Npart -- which is related to energy density -- with your 
statement that there are questions about sensitivity to the initial energy 
density. This seems to be exactly what these results are sensitive to.
But maybe I am misunderstanding what "raises questions" meant, in which case 
some different language could be used. Maybe you meant instead that it leads 
to future possibilities to explore the role of geometry in heavy-ion 
collisions.


> On Jul 26, 2023, at 2:23 AM, Nihar Sahoo via Star-hp-l 
> <star-hp-l AT lists.bnl.gov> wrote:
>
> Hello All,
>
> Sorry for this late submission of my proceedings on HP2023 STAR highlights.
>
> I requested HP2023 organizers to consider my late submission by email and 
> they agreed to consider it.
> So it would be Ok from their side.
>
> As you know, Joern Putschke kindly presented for me at HP2023. However, he 
> suggested me to put only my name for the STAR collaboration in these 
> proceedings. If there is any STAR rule in this direction, please let us 
> know.
>
> Please have a look at my HP2023 proceedings on STAR highlights.
>
> Thank you
> Nihar
>
>
>
>
> On 2023-07-26 11:38, webmaster--- via Star-hp-l wrote:
>> Dear Star-hp-l AT lists.bnl.gov members,
>> Nihar Sahoo (nihar AT rcf.rhic.bnl.gov) has submitted a material for a review,
>> please have a look:
>> https://drupal.star.bnl.gov/STAR/node/64418
>> ---
>> If you have any problems with the review process, please contact
>> webmaster@http://www.star.bnl.gov/
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