STAR HardProbes PWG

[Youqi Song <youqi.song AT yale.edu>]

Hi Nihar,

Thanks for the thoughtful comments! I have implemented them and uploaded a version 3 to the drupal page. Please find my response below.

Best,

Youqi

L7: "   …while maintaining most of the low-momentum …" -> It is not clear,
please rephrase this.

fixed - I have rephrased this to "By removing collinear radiation while *retaining* most of the low-momentum (soft) radiation components *of the jet*"

L12: "…the formation time …" -> when we mention "formation time of
splitting" it would be better to make it clear what splitting ? Is it
hadronic or parsonic level? [Need such discussion in Intro too]

We are trying to limit the characters in the abstract to no more than 600, so we keep this discussion in the body of the paper.

 

L13:"…non-perturbative effects …" -> Need to elaborate like
"non-perturbative QCD effects …" [need to introduce QCD in the abstract
otherwise it is not clear "perturbative" and "non-perturbative" of
what?]

fixed

L19: in coming quarks and gluons (partons)  -> in coming partons

fixed

 

L21 "… a high-momentum virtual particle" and again L23 "highly virtual";
you can merge these two sentences.

fixed - Sorry for the confusion. The particle in L21 refers to the gluon exchange and in L23 refers to the outgoing partons. I have changed the second sentence to "Such outgoing partons are *also* highly virtual".

L24: "a series of splitting processes" -> for general reader you need to
explain what is that "splitting process"? Like "vacuum gluon radiation"

fixed

 

L38: "…the non-perturbative components of the parton shower …" > Could
you explain what is the non-perturbative components of the parton shower?

fixed - I changed this to "... the non-perturbative components of the parton shower (e.g. soft gluon emission \cite{atlas_lund}, \cite{cms_lund}) ..." I cited the Lund Plane measurements by ATLAS and CMS, where they both explained that the splittings with k_T = pT,2 * delta R < 1 GeV are considered non-perturbative. I think this means that when the pT of the softer subjet, pT,2, is less than about 2 GeV (e.g. through soft gluon emission), we would have a non-perturbative parton shower.

L52: "To enhance perturbative contributions …" -> Is this the correct
way to phrase?  Using SoftDrop grooming we try to study pQCD
contribution to jet. So if you agree, please rephrase.

fixed - Changed to "To enhance the pQCD contributions in jet, ..."

_To explain soft drop grooming, you may consider to include one cartoon.
Just a suggestion.

Since we are going for PRL we tried to limit the number of figures to not more than 3.

L69: The z and R…
          "the momentum imbalance" -> is this correct for "z"? Is not
that "momentum fraction"?

fixed

L98-100: Provide reference.

We showed these simulation studies in analysis note section 6.5.1.

L154-155: We apply the selections of pT > 15 GeV/c, |η| < 0.6,.. -> here
you need to mention these are jet pT and eta; better to use notation
like p_T,jet, eta_jet

fixed

L161-167: This discussion on SD1 and SD2 cuts can be moved to, after
L112, where you discuss "a" and and also M_(g). Otherwise, there is a
confusion while reading that para why we use "M-M_g" (even reader like
me also).

fixed - I have rearranged the paragraphs from (current) L79-113 and L165-171, so that I keep SD1, SD2 and the definition of CollinearDrop groomed mass general in the introduction section, and bring up the specific SD1 and SD2 that is used in this analysis in the analysis details section.

Eq(5). You have not introduced pT,jet

fixed - added "$p_{\mathrm{Tjet}}$ is the transverse momentum of the jet." after Eq (5).

L279-280: x% and y%; when do you think to include? Same for L318, L319, L333

These numbers will be finalized after we repeat this analysis with the new embedding (which is not ready yet).

L324: …for a jet of 20 GeV -> 20 GeV/c

fixed

FIg.1, Y-axis title ?  pT unit "GeV/c"

fixed

L344: …indicating that the CollinearDrop groomed mass is sensitive to
hadronization effects. -> Why for 30-50 GeV/c case, both SCET and MC
simulations are the same unlike 20-30 GeV/c? Do you understand this? Is
that statement true for 30-50 GeV/c?

We are still waiting for SCET calculations for 30-50 GeV/c. The red bands shown in both the 20-30 GeV/c panel and 30-50 GeV/c panel are from uncertainty on data.

 

L358: formation time t, -> Formation time of what?

This is the formation time it takes for a parton to radiate a gluon, as we explained in the same sentence.

Fig.3: resolution of this plot should be enhanced.  Currently insert one
is not good.

fixed - I removed the insert in Fig 3, and put the green boxes that illustrate the regions on Fig 2.

On Mon, Apr 8, 2024 at 9:56 AM Nihar Sahoo <nihar AT rcf.rhic.bnl.gov> wrote:

Hello Youqi,

Here are my comments on this nice measurement and paper draft. I hope
detailed discussion will be at the GPC level.
With these comments addressed, I sign off.


L7: "   …while maintaining most of the low-momentum …" -> It is not clear,
please rephrase this.
L12: "…the formation time …" -> when we mention "formation time of
splitting" it would be better to make it clear what splitting ? Is it
hadronic or parsonic level? [Need such discussion in Intro too]
L13:"…non-perturbative effects …" -> Need to elaborate like
"non-perturbative QCD effects …" [need to introduce QCD in the abstract
otherwise it is not clear "perturbative" and "non-perturbative" of
what?]
L19: in coming quarks and gluons (partons)  -> in coming partons
L21 "… a high-momentum virtual particle" and again L23 "highly virtual";
you can merge these two sentences.
L24: "a series of splitting processes" -> for general reader you need to
explain what is that "splitting process"? Like "vacuum gluon radiation"
L38: "…the non-perturbative components of the parton shower …" > Could
you explain what is the non-perturbative components of the parton shower
?
L52: "To enhance perturbative contributions …" -> Is this the correct
way to phrase?  Using SoftDrop grooming we try to study pQCD
contribution to jet. So if you agree, please rephrase.

_To explain soft drop grooming, you may consider to include one cartoon.
Just a suggestion.

L69: The z and R…
          "the momentum imbalance" -> is this correct for "z"? Is not
that "momentum fraction"?
L98-100: Provide reference.

L154-155: We apply the selections of pT > 15 GeV/c, |η| < 0.6,.. -> here
you need to mention these are jet pT and eta; better to use notation
like p_T,jet, eta_jet

L161-167: This discussion on SD1 and SD2 cuts can be moved to, after
L112, where you discuss "a" and and also M_(g). Otherwise, there is a
confusion while reading that para why we use "M-M_g" (even reader like
me also).

Eq(5). You have not introduced pT,jet
L279-280: x% and y%; when do you think to include? Same for L318, L319,
L333
L324: …for a jet of 20 GeV -> 20 GeV/c


FIg.1, Y-axis title ?  pT unit "GeV/c"

L344: …indicating that the CollinearDrop groomed mass is sensitive to
hadronization effects. -> Why for 30-50 GeV/c case, both SCET and MC
simulations are the same unlike 20-30 GeV/c? Do you understand this? Is
that statement  true for 30-50 GeV/c?

L358: formation time t, -> Formation time of what?
Fig.3: resolution of this plot should be enhanced.  Currently insert one
is not good.


Best
Nihar

On 2024-03-12 03:36, Youqi Song via Star-hp-l wrote:
> Hi all,
>
> Please find my paper draft and analysis note here and let me know if
> you have any comments or suggestions! I plan to request for GPC
> formation during the collaboration meeting. Here is the drupal page:
>
> https://drupal.star.bnl.gov/STAR/blog/youqi/Measurement-collinear-drop-jet-mass-and-its-correlation-groomed-jet-substructure-observab.
>
> Best,
> Youqi
> _______________________________________________
> Star-hp-l mailing list
> Star-hp-l AT lists.bnl.gov
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