STAR HardProbes PWG

[wy157543 AT mail.ustc.edu.cn]

Hi Isaac,

Just a gentle reminder to check if you have any further comments on the paper 
or the analysis note.

Best regards,
Yan

> -----原始邮件-----
> 发件人: tc88qy <tc88qy AT rcf.rhic.bnl.gov>
> 发送时间:2025-01-13 14:10:34 (星期一)
> 收件人: star-hp-l AT lists.bnl.gov
> 抄送: "Nihar Sahoo" <nihar AT rcf.rhic.bnl.gov>
> 主题: Re: [[Star-hp-l] ] Measurement of ψ(2S) production in Ru+Ru and Zr+Zr 
> collisions at 200 GeV is Ready for PWG Review
> 
> Hi Nihar,
> 
>     I am one of the PA. So it needs you and Isaac to sign-off.
> 
> Qian Yang
> 
> On 2025-01-11 09:51, Nihar Sahoo wrote:
> > Hello PAs,
> > 
> > Thank you for addressing my comments.
> > At the moment, I don't have any further comments. I sign off.
> > Once Isaac and Qian will sign it off , we can request PAC to form GPC.
> > Please remind us next week if you will not receive any comments.
> > 
> > Best
> > Nihar
> > 
> > On 2025-01-09 16:26, wy157543 wrote:
> >> Hi Nihar and Isaac,
> >> 
> >> Thank you for your kind comments. The paper and note have been updated
> >> and can be accessed at the following links:
> >> https://drupal.star.bnl.gov/STAR/system/files/psi2s_paper_pwg_v2.pdf
> >> https://drupal.star.bnl.gov/STAR/system/files/psi2s_note_pwg_v2.pdf
> >> 
> >> Below are the detailed replies.
> >> 
> >> For paper:
> >> 
> >> Title: “First observation of charmonium sequential suppression in
> >> heavy-ion collisions at  Relativistic Heavy Ion Collider” -> “
> >> Measurement of charmonium sequential suppression in heavy-ion 
> >> collisions
> >> at  Relativistic Heavy Ion Collider”  [ “First …” in title sounds
> >> awkward and a reader can judge it. ]
> >> 
> >> I removed the "First" and kept the observation
> >> --------
> >> 
> >> Line7: "We report on measurements of charmonium …” -> “We report the
> >> measurement of charmonium …”
> >> 
> >> Done.
> >> --------
> >> 
> >> L48-51: “…has  been measured in Pb+Pb collisions at …” Better to
> >> mention what we observed at the LHC experiments and what more
> >> information we can get at RHIC measurement and why it is important to
> >> measure at RHIC energy.
> >> 
> >> Done.  The importence for psi2s measurements is described on lines 
> >> 60-76
> >> --------
> >> 
> >> L90-92: This sentence sounds redundant and you already mentioned in
> >> intro. Please drop it.
> >> 
> >> Done.
> >> --------
> >> 
> >> L138: “… from data for different BDT cuts, “ it is not clear from the
> >> text what are BDT cuts. Please elaborate and avoid words like “cuts”.
> >> Use condition or criteria, etc. [Similarly for other places]
> >> 
> >> BDT cut->BDT threshold,
> >> Added "by requiring the BDT response to be above a threshold." on
> >> line133-134 to introduce "BDT threshold".
> >> --------
> >> 
> >> _ Many places “200 GeV” is used, use “ \sqrt s_NN = 200 GeV”
> >> 
> >> Done.
> >> --------
> >> 
> >> _ It would be important to point out that what is advantage of using
> >> BDT/ supervised ML technique over traditional invariant Mass
> >> combinatorial subtraction method. A account will enhance this paper.
> >> Please indicate if such comparisons are discussed in AN.
> >> 
> >> The comparison was added in AN (319-322): The jpsi significence is
> >> improved from 133 (traditional method) to 170  (ML method) the ML
> >> technique did significantly improve signal salience.
> >> --------
> >> 
> >> _ L280-289: “While all three measurements are consistent within
> >> uncertainties, the centrality dependence in 200 GeV Ru+Ru and Zr+Zr
> >> collisions seem to more closely resemble the measurements at 17.3 
> >> GeV…”
> >> This is not true within uncertainty . “…seem to more closely 
> >> resemble….”
> >> Please paraphrase.
> >> 
> >> The original content is modified to：
> >> While all three measurements are consistent within uncertainties  at
> >> comparable $\langle N_{\rm part} \rangle$ values, the centrality
> >> dependence trend observed  in $\sqrt{s_{_{\rm NN}}}$ = 200 GeV Ru+Ru
> >> and Zr+Zr collisions seems to more closely resembles
> >> the measurements at 17.3 GeV than those at 5.02 TeV.
> >> 
> >> "at comparable $\langle N_{\rm part} \rangle$" and "trend" were added
> >> to make the expression clearer.
> >> --------
> >> 
> >> I think it would be better to make Fig,3 as final money plot for this
> >> paper. Whereas Fig.4 and it discussion should come before double ratio
> >> vs Npart plot.
> >> I find Ratio vs pT plot is less significant, due to uncertainty, than
> >> current Fig.3 to convey the message.
> >> 
> >> Fig,3 does convey the more important message. However, if the
> >> positions of Fig,3, Fig,4 are exchanged, it is a little strange to
> >> discuss ratio instead of double ratio after calculating pp, pA
> >> reference. If Fig,4 is placed before calculating pp, pA reference, the
> >> discussion of physical results is separated. Another reason is that
> >> Fig,3 contains calculations from both models, and therefore they can
> >> be introduced together. Personally, I think it would be better to keep
> >> the current order. it is not necessary that the money.
> >> --------
> >> 
> >> Fig.3:
> >> _ Please add in the legend what is that gray band on unity line. It is
> >> unclear.
> >> _ Can we have p/d+Au 200 GeV CNM effect calculation from Tsinghua 
> >> group?
> >> That would even strengthen the claim.
> >> 
> >> _ Is there any discussion or information on QGP Temperature from
> >> Tsinghua's group calculation?
> >> 
> >> 
> >> Added " The band at unity represents the relative uncertainty in
> >> interpolated $\psi$(2S) to J/$\psi$
> >> ratio in $p$+$p$ collisions." to the captain.
> >> Regarding the calculation of "CNM effect" and "QGP Temperature",
> >> we may need to further consult Tsinghua group.
> >> --------
> >> 
> >> ---
> >> ----------------------------------------------------------
> >> ---
> >> For note:
> >> 
> >> 142. I see that after applying the procedure, there is still a
> >> residual eta dependence although the phi dependence is nicely removed.
> >> Is this caused by the imperfect agreement of the fit with the data
> >> especially in the negative rapidity region? Is this non-zero nsigma_e
> >> close enough to zero that it produces a minimal effect in the
> >> analysis?
> >> 
> >> 
> >> Yes, the slight \eta dependence that still exists after recalibration
> >> does result from slight differences between the fit results and the
> >> data, but these differences have little effect on the analysis
> >> results. Because the recalibration is only convenient for the
> >> selection of nsigmaE cut and the calculation of nsigmaE cut
> >> efficiency. In addition, the small deviation is taken into account in
> >> efficiency correction since the correction is estimated with a
> >> data-driven method.
> >> 
> >> ---
> >> 
> >> 175. Just to make sure I understand, this cut on the invariant mass
> >> implies that only Dalitz decays of pi0s are included in the sample,
> >> while photon conversion typically falls just outside the requirement,
> >> right?
> >> 
> >> Electrons from Dalitz decay are equally good for estimating
> >> efficiencies compared to photon conversion. What matters is the
> >> electron purity, not its source. The selection of the pairMass cut
> >> takes into account both the statistics and the electron purity.
> >> For example, in 40–80% centrality, photon conversions are also
> >> included to increase statistics. (New 20-40% and 40-80% centrality
> >> graphs added)
> >> 
> >> ---
> >> 
> >> 204. This isn't 100% true is it? We see in the Background plot in Fig.
> >> 11 that the track pT or p has a correlation of ~ 0.25 for example. And
> >> this makes sense given the relation between invariant mass and
> >> momentum. Did you check whether the results were modified
> >> significantly if the observables which have some degree of correlation
> >> with the pairMass were removed from consideration as training
> >> features?
> >> 
> >> Fig. 11 includes more information than the features used in ML. Only
> >> the features shown in Fig. 17 have been used for identification,
> >> all of which have low correlation with pairMass. More detail describes
> >> for the features used in ML is added in AN (190-200)
> >> ---
> >> 
> >> Eq. 4. I understand the procedure you're following to change the mean
> >> and sigma of the embedding nsigma distributions, but the subscripts
> >> 1,2,3 were a little confusing to me for a second. Could you either
> >> explicitly explain them in the text (e.g. "the numerical subscripts
> >> refer to a value in the embedding at the corresponding step in the
> >> correction procedure" or similar), or use a less opaque notation?
> >> 
> >> Thanks for your reminding, I have added some content to better
> >> describe these steps. (222-227)
> >> 
> >> ---
> >> 219. Sorry for this possibly silly question, but isn't there a concern
> >> that if you use embedding for signal and data for background that the
> >> model may distinguish the two based on some subtle difference not
> >> between signal and background but between embedding and data (that is
> >> left over after the feature alignment procedure)? Was the training
> >> tried with embedding for background as well, and if so was it
> >> approximately the same result?
> >> 
> >> 
> >> We do not see the need to use embedding for background since utilizing
> >> data is always better. In fact, we do not have embedding for
> >> background since our simulation only embeds psi(2S) signal. Then the
> >> question is whether there is any residual difference between data and
> >> embedding after the alignment procedure, and if so how would that
> >> affect the results. We do not have a clear answer to that since if we
> >> know there is a difference we would have corrected it. What we can do
> >> is to check the dependence of corrected Jpsi and psi(2S) counts, with
> >> raw counts from data and efficiency from machine learning, on the BDT
> >> response. A flat distribution is seen in Fig. 19, which shows that
> >> embedding agrees with data quite well after alignment. Furthermore,
> >> variations in the results from using different BDT cuts are included
> >> in the uncertainty, which is another way to gauge the difference
> >> between data and embedding
> >> ---
> >> 
> >> Fig. 15. Just curious, what is the y-axis here? Is it bin-width and
> >> integral-normalized count? Or something else?
> >> 
> >> Yes, it's normalized count
> >> 
> >> ---
> >> 
> >> Fig. 20. I can't tell if my eye is fooling me or not, but it looks
> >> like the relative statistical uncertainties on the 0-80% range are
> >> slightly bigger than the 40-80% range. Is this true?
> >> 
> >> Yes, this is true for ψ(2S). Because more significant suppression in
> >> central collisions for psi(2S) results in worse signal to background
> >> ratio.
> >> (At BDT cut = 0.7, the signal significance is only 1.7σ.)
> >> 
> >> ---
> >> 
> >> Fig. 25. What should we make of the fact that the Crystal Ball fits
> >> are quite poor?
> >> 
> >> Indeed, the templates obtained by ToyMC cannot be perfectly described
> >> by the Crystal Ball function. This is an interesting feature and we
> >> will continue to investigate that. However, what we take from the
> >> fitting are the ratios of various Crystal-ball parameters between Jpsi
> >> and psi(2S), which should still be good even if the templates do not
> >> fit ver well. In data analysis, Jpsi peak is fit with all Crystal-ball
> >> function parameters being free (the fit works well as seen in Figs. 26
> >> and 27), while psi(2S) peak fit is constrained by Jpsi fit parameters
> >> and the parameter ratios from ToyMC.
> >> ---
> >> 
> >> Fig. 28. What is causing the bump ~ 500 MeV? Comparing to e.g.
> >> https://drupal.star.bnl.gov/STAR/system/files/JianZhou_hf_20220120_v3.pdf
> >> s. 14 [from run 16], this bump does appear but a) to a seemingly
> >> lesser extent (for the same set of cuts), and b) with more of a
> >> centrality dependence. Do you have an insight into the difference?
> >> 
> >> In terms of the bump, I always think that comes from interplay of two 
> >> effects:
> >> i) efficiency increases with pt as electron's dE/dx increases with pt
> >> and thus more likely to generate a TPC hit, and also the track length
> >> increases with pt;
> >> ii) on the other hand, electron's efficiency decreases with pt since
> >> at low pt electron tracks can bend through TPC boundaries and still
> >> get reconstructed while at high pt electron tracks are straight and
> >> they are more likely to be lost in the boundaries.
> >> 
> >> The major differences between Jian's analysis and this analysis are
> >> high luminosity in run16 which could affects TPC performance in terms
> >> of the bump. The variation in TPC occupancy from central to peripheral
> >> events is much larger for Au+Au than for Isobar, which is why Jian
> >> seems a larger centrality
> >> dependence
> >> 
> >> 
> >> Best,
> >> 
> >> Yan and PAs
> >> 
> >> 
> >> 
> >>> -----原始邮件-----
> >>> 发件人: "Mooney, Isaac" <isaac.mooney AT yale.edu>
> >>> 发送时间:2025-01-05 09:06:27 (星期日)
> >>> 收件人: "star-hp-l AT lists.bnl.gov" <star-hp-l AT lists.bnl.gov>
> >>> 主题: Re: [[Star-hp-l] ] Measurement of ψ(2S) production in Ru+Ru and 
> >>> Zr+Zr collisions at 200 GeV is Ready for PWG Review
> >>> 
> >>> Hi Yan and PAs,
> >>> 
> >>> Due to my delay in reviewing the materials, I focused on the analysis 
> >>> note as the paper draft can be tuned up during the GPC if necessary. 
> >>> Congratulations to you on an extremely well-written note. I have a 
> >>> handful of comments below, and I find that the analysis is ready to 
> >>> move to GPC formation, pending any input from Qian. I may send 
> >>> comments on the paper draft at some point, but that doesn’t need to 
> >>> delay the formation request.
> >>> 
> >>> Thanks,
> >>> Isaac
> >>> 
> >>> 142. I see that after applying the procedure, there is still a 
> >>> residual eta dependence although the phi dependence is nicely 
> >>> removed. Is this caused by the imperfect agreement of the fit with 
> >>> the data especially in the negative rapidity region? Is this non-zero 
> >>> nsigma_e close enough to zero that it produces a minimal effect in 
> >>> the analysis?
> >>> 
> >>> 175. Just to make sure I understand, this cut on the invariant mass 
> >>> implies that only Dalitz decays of pi0s are included in the sample, 
> >>> while photon conversion typically falls just outside the requirement, 
> >>> right?
> >>> 
> >>> 204. This isn't 100% true is it? We see in the Background plot in 
> >>> Fig. 11 that the track pT or p has a correlation of ~ 0.25 for 
> >>> example. And this makes sense given the relation between invariant 
> >>> mass and momentum. Did you check whether the results were modified 
> >>> significantly if the observables which have some degree of 
> >>> correlation with the pairMass were removed from consideration as 
> >>> training features?
> >>> 
> >>> Eq. 4. I understand the procedure you're following to change the mean 
> >>> and sigma of the embedding nsigma distributions, but the subscripts 
> >>> 1,2,3 were a little confusing to me for a second. Could you either 
> >>> explicitly explain them in the text (e.g. "the numerical subscripts 
> >>> refer to a value in the embedding at the corresponding step in the 
> >>> correction procedure" or similar), or use a less opaque notation?
> >>> 
> >>> 219. Sorry for this possibly silly question, but isn't there a 
> >>> concern that if you use embedding for signal and data for background 
> >>> that the model may distinguish the two based on some subtle 
> >>> difference not between signal and background but between embedding 
> >>> and data (that is left over after the feature alignment procedure)? 
> >>> Was the training tried with embedding for background as well, and if 
> >>> so was it approximately the same result?
> >>> 
> >>> Fig. 15. Just curious, what is the y-axis here? Is it bin-width and 
> >>> integral-normalized count? Or something else?
> >>> 
> >>> Fig. 20. I can't tell if my eye is fooling me or not, but it looks 
> >>> like the relative statistical uncertainties on the 0-80% range are 
> >>> slightly bigger than the 40-80% range. Is this true?
> >>> 
> >>> Fig. 25. What should we make of the fact that the Crystal Ball fits 
> >>> are quite poor?
> >>> 
> >>> Fig. 28. What is causing the bump ~ 500 MeV? Comparing to e.g. 
> >>> https://drupal.star.bnl.gov/STAR/system/files/JianZhou_hf_20220120_v3.pdf
> >>>  
> >>> s. 14 [from run 16], this bump does appear but a) to a seemingly 
> >>> lesser extent (for the same set of cuts), and b) with more of a 
> >>> centrality dependence. Do you have an insight into the difference?
> >>> 
> >>> > On Dec 24, 2024, at 02:04, Nihar Sahoo <nihar AT rcf.rhic.bnl.gov> wrote:
> >>> >
> >>> > Dear PAs,
> >>> >
> >>> > I have gone through the AN and paper draft. I find both the materials 
> >>> > in good shape, besides my following comments.
> >>> > Please take a look at my comments below.
> >>> > If Isaac and Qian will sign off with all these comments, then we can 
> >>> > request for the GPC formation around 1st week of January.
> >>> >
> >>> >
> >>> > Title: “First observation of charmonium sequential suppression in 
> >>> > heavy-ion collisions at  Relativistic Heavy Ion Collider” -> “ 
> >>> > Measurement of charmonium sequential suppression in heavy-ion 
> >>> > collisions at  Relativistic Heavy Ion Collider”  [ “First …” in title 
> >>> > sounds awkward and a reader can judge it. ]
> >>> >
> >>> > Line7: "We report on measurements of charmonium …” -> “We report the 
> >>> > measurement of charmonium …”
> >>> >
> >>> > L48-51: “…has  been measured in Pb+Pb collisions at …” Better to 
> >>> > mention what we observed at the LHC experiments and what more 
> >>> > information we can get at RHIC measurement and why it is important to 
> >>> > measure at RHIC energy.
> >>> >
> >>> > L90-92: This sentence sounds redundant and you already mentioned in 
> >>> > intro. Please drop it.
> >>> >
> >>> > L138: “… from data for different BDT cuts, “ it is not clear from the 
> >>> > text what are BDT cuts. Please elaborate and avoid words like “cuts”. 
> >>> > Use condition or criteria, etc. [Similarly for other places]
> >>> >
> >>> > _ Many places “200 GeV” is used, use “ \sqrt s_NN = 200 GeV”
> >>> >
> >>> > _ It would be important to point out that what is advantage of using 
> >>> > BDT/ supervised ML technique over traditional invariant Mass 
> >>> > combinatorial subtraction method. A account will enhance this paper. 
> >>> > Please indicate if such comparisons are discussed in AN.
> >>> >
> >>> > _ L280-289: “While all three measurements are consistent within 
> >>> > uncertainties, the centrality dependence in 200 GeV Ru+Ru and Zr+Zr 
> >>> > collisions seem to more closely resemble the measurements at 17.3 
> >>> > GeV…” This is not true within uncertainty . “…seem to more closely 
> >>> > resemble….” Please paraphrase .
> >>> >
> >>> > I think it would be better to make Fig,3 as final money plot for this 
> >>> > paper. Whereas Fig.4 and it discussion should come before double 
> >>> > ratio vs Npart plot.
> >>> > I find Ratio vs pT plot is less significant, due to uncertainty, than 
> >>> > current Fig.3 to convey the message.
> >>> >
> >>> > Fig.3:
> >>> > _ Please add in the legend what is that gray band on unity line. It 
> >>> > is unclear.
> >>> > _ Can we have p/d+Au 200 GeV CNM effect calculation from Tsinghua 
> >>> > group? That would even strengthen the claim.
> >>> >
> >>> > _ Is there any discussion or information on QGP Temperature from 
> >>> > Tsinghua's group calculation?
> >>> >
> >>> > Thank you
> >>> > Nihar
> >>> >
> >>> >
> >>> > On 2024-11-02 16:21, wy157543 wrote:
> >>> >> Dear HPs,
> >>> >> The paper draft and analysis note for “First observation of
> >>> >> charmonium sequential suppression in heavy-ion collisions at
> >>> >> Relativistic Heavy Ion Collider” are ready for pwg review. The
> >>> >> associated documents can be found as follows:
> >>> >> Webpage:
> >>> >> https://drupal.star.bnl.gov/STAR/blog/wy157543/Measurement-psi2S-production-RuRu-and-ZrZr-collisions-200-GeV-0
> >>> >> Paper
> >>> >> draft:https://drupal.star.bnl.gov/STAR/system/files/psi2s_paper_pwg.pdf
> >>> >> Analysis note:
> >>> >> https://drupal.star.bnl.gov/STAR/system/files/psi2s_note_pwg.pdf
> >>> >> We would appreciate it if you could review the documents and provide
> >>> >> us with your valuable comments and suggestions!
> >>> >> Best regards,
> >>> >> Yan for PAs
> >>>