STAR HardProbes PWG

[Barbara Trzeciak <barbara.trzeciak AT gmail.com>]

Hi Leszek,

please find below comments to your paper draft (v6).

Cheers,

Barbara

- L27-31: I would move it further in the introduction and start with the 'standard' intro from L32.

- L32: A crucial part in this topic is the quarkonium production mechanism, which is not fully understood -> Despite decades of studies, the quarkonium production mechanism is still not fully understood. 

- L35-36: through one of the Color Singlet or Color Octet states -> through either a color singlet or a color octet state. 

- L36 - 37: "and is described by either Color Singlet Model ... in Non-Relativistic QCD framework". There is not really Color Octet Model, there are models that either take into account only the color-singlet mechanism or add to it the contribution from the color-octet mechanism. 

I propose something like:

"Different theoretical approaches can be distinguished based on which sub-process they take into account. The Color Single Model [] assumes quarkonium production via the color singlet mechanism only. Both the color singlet and the color octet mechanisms are integrated within the framework of the Non-Relativistic QCD (NRQCD) effective field theory [] ..... The third class of models is (Improved) Colour Evaporation Model [] that assumes democracy of different color states."

- L39-40:  Measurements of Υ production in p+p collisions are a test of these models. ->  Measurements of Υ production in p+p collisions provide tests of different models and constraints on the models’ free parameters.

- L40: " This is the purpose ... " - I would remove this sentence from here and add a paragraph at the end of this section describing what results are included in this paper. 

- L56: add the trigger condition, energy threshold. 

- L59: is provided -> are provided

- L61: explain E/p

- L64: Data Analysis - the information in the section is a bit mixed, I would propose to reshuffle content so that each step of the analysis is more clear.

   - L65-67: this paragraph can be moved to the previous section.

   - I would then make the following section: Upsilon signal reconstruction, where you describe the track quality cuts (L68-75), then the electron identification (current A) and finally the Upsilon signal reconstruction (current B). 

   - I think it's important to have an additional separate subsection on how the multiplicity distribution is determined - L76-83. But this paragraph should be made more clear. I.e. I would write " Thus, similar cuts are used as for electron tracks with a few differences." but directly list all the selections. Also, it would be more clear if corrections that are applied on the TofMult to get the Nch distributions were described in the same section. Separately from the efficiency corrections for the Upsilon signals. Also, I'm missing some plot in the paper related to the Nch determination - e.g. similar to Fig. 3 in the J/psi vs mult paper.  

- L73: Furthermore split -> Furthermore, split

- L73: by using a cut -> by cutting 

- L75: "Finally tracks with bad dE/dx values ..." - this is quite technical and probably not needed here. One may ask what are tracks with bad dE/dx

- L81: limiting pile-up -> large pile-up (?)

- L81: "using matching to TOF hits" - this is not clear for an outside reader

- L83:  is in called in this study as TOF multiplicity -> is called in this study a TOF multiplicity

- L88: pions -> hadrons

- L90: add reference to SMD

- L91: "RSMD < 0.028" -  in order to understand this number, you should add (here or earlier in the text) what's the size of a BEMC tower.

- L91: information from the cluster on shower shape -> information on shower shape

- L91: you should explain what shower shape is. And I would move this sentence at the end of this paragraph, after you describe the energy cuts. 

- L92:  Electrons should -> In addition, electron should 

- L92: fraction of energy -> fraction of its energy

- L94: remove "which do not leave much energy in the EM calorimeter". "In contrast" already says it all. 

- L97-98: "one of the electron" - you should add a footnote that you use "electron" for both electrons and positrons in further text, unless otherwise specified

- L98: it's the first place that you mention L0 trigger, should be explained earlier where you describe your data and triggers.

- L99: "for the partner track" - it might not be clear what partner track is. I would just say second electron

- L99-100: "An invariant mass is calculated for each pair and a histogram is filled. Unlike sign pairs contain signal as well as combinatorial and residual backgrounds" - the wording is too technical for a paper, e.g. it's not important you fill a histogram. Please try to rephrase, e.g.

"Electrons and positrons that pass all the selection requirements are paired and their invariant mass is calculated, as shown in Fig. 1. In addition to the Upsilon signal, there are also contributions from combinatorial and the correlated residual backgrounds.".

- L102: sign pairs -> sign pairs, e+e+ + e-e-

- L102: remove "on the other hand"

- L103: The Figure 1 -> Figure 1

- L115-116: global fits -> global fit values

- L122: The Figure 2a -> Figure 2(a)

- L124: remove "however"

- L126: "in a similar way " - similar to what ?

- L128: Figure 2b -> Fig. 2(b)

- L130: the corrected signal -> the Upsilon corrected signal

- L140-141: "the influence of possible pile-up tracks should be negligible" - is it really negligible or very small ? And is there any uncertainty due to the pile-up assigned for N_ch/<N_ch> and N_Upsilon/<N_Upsilon> ?

- L141-142: "This allowed to increase the DCA cut from DCA < 0.5 cm to DCA < 1 cm, which reduces T ofMult fluctuations." This might be a bit confusing for the reader, which cut you finally use and for which case. Please make it more clear, put all the info in one place and make it consistent. 

- Table I, II, IV: Fit -> Raw yield extraction

Tracking -> Tracking efficiency

- Table I, II - you can merge them.

- Table III - By "Trigger" you mean HT trigger or the BBC trigger  unc. ? 

Also, in the text you don't consider the trigger unc. as part of the correlated unc. There seems to be confusion between the HT trigger and the BBC trigger efficiency uncertainties. The first one, that you describe in L158-160, should be in Tab. I (not sure why it should be correlated). And then the normalization uncertainties should include the BBC trigger unc., and should be described in the text. 

- the total uncorrelated unc. given in the tables don't match the text. 

- Why is the nSigmaE sys. uncertainty treated as a global correlated uncertainty ?  

- What about other electron identification efficiency uncertainties, i.e. BEMC matching and E/p cut efficiency ?

- Also, I would make the separation of the unc. in a bit different way. Put everything to one table, commenting in the text in case some of the uncertainties are correlated (and in what variable, see the comment below), separating out only the global normalization uncertainties:  luminosity, vertex and BBC trigger. 

- Since you have signal vs different variables, when you write about correlation between uncertainties you should specify w.r.t. to which variable. E.g. correlated in pT or y or N_ch. 

And how do you exactly determine if a given uncertainty is correlated ?

- L148: studied by fixing -> fixing to what ?

- L149: When estimating -> When obtaining 

- L150: momentum resolution had to be corrected -> electron momentum resolution was smeared 

- L156: assumed Υ polarization -> assumed no Υ polarization

- L158-159: The trigger response in the simulation may have a small difference from the data -> The trigger response may be not well simulated. 

- L159: ADC counts are not explained anywhere

- L159:  "was found to differ by 3% [39]," - but the paper you refer to is for a different dataset. You should estimate it for your data and simulations separately.

- L159: "which affects the yield by ±8.7%." - but you don't write how this sys. unc. was obtained, you only write that there's a difference in ADC counts but not how it's used to calculate the sys. unc.

- L161: "total uncorrelated systematic " - it's not written how the total is obtained.

- L165-166: "Acceptance variation due to fluctuating BEMC towers during the run, which is later applied in the simulation gives the effect of ±3% [39]" - this source is not clear, also I don't see any explanation in ref. [39].

- L171: "Furthermore a 4Cx PYTHIA tune which uses a different ..." - you should explicitly say here that you use a different PYTHIA tune to build a new response matrix for the unfolding. 

- L174: "any change" you mean it's flat ?

- L175:  fitting it with a line -> fitting the Upsilon reconstruction efficiency vs multiplicity with a pol1

- L175-176: "as an input to the unfolding procedure" - it's not clear how do you propagate Upsilon efficiency to the N_ch unfolding. 

- L177-178: "the shape of the Nch distribution for min-bias events, which is checked by replacing the measured distribution with a fit of negative binomial distribution" - it's not clear why you compare N_ch distribution to NBD, is it to check the pile-up effects as in the case of the analysis of J/psi vs mult. ? If so, it would be good to make it clear in the text and replace "N_ch from NBD" with "pile-up" in the table - the sources of the sys. unc. should alway say what effect we want to probe, not what change was done. They also take into account the difference in the nch distribution between the lowest and highest coincidence rate, have you checked this ?

- Also "Iterations" and "4Cx tune" probe unfolding. I would merge these two sources in Tab. IV and Tab. V and name them "unfolding" in the table. 

- "Tracking" uncertainty from Tab. V is not described in L168-180.

- L184: Figure 3 -> Fig. 3

- L183: After applying reconstruction efficiency corrections, the differential -> The differential. 

And explain each contribution below the equation.

- L186: The value of integrated -> The integrated

- L186: is measured to be -> is

- L187: the measured value is -> the cross section is

- L187-188: "which is consistent" - consistent with what ? 

- L188: move references after "at different energies"

- L188: Figure 3 -> Fig. 3

- L190-191: remove "The only exception is ..."

- L191: both calculations -> CEM and CSM calculations

- L192: while contribution -> while the contribution

- L192-194: "The NLO calculation is below the LO at high energy ... " - these sentences comment on the model, they don't seem to be relevant for this paper. 

- L195: were also calculated and shown -> are shown

- L195: Figure 4a and Figure 4b respectively -> Fig. 4(a) and Fig. 4(b), respectively, for Υ(1S + 2S + 3S) (red circles), Υ(2S + 3S) (blue squares), and for each Upsilon state separately. 

- L196: "The data allowed separation ... " - this is rather for the "Signal reconstruction section", here just write what are the results. 

- L199-200: however a dip is observed in Υ(3S) which differs 2σ from flat distribution. -> and a 2σ significant dip is observed for the Υ(3S) state. 

- L200: This is probably a downward fluctuation present already in the raw -> This is a downward fluctuation in the raw

- L201: state was checked and it behaves similarly to other -> is similar to other

- L202-203: " and it drops by a factor of 2 towards forward/backward ...  as expected" - I would remove this. You can add a sentence about the y dependence of the efficiency in the "Efficiency corrections" section.

- L203: " Furthermore, the raw Υ(3S) signal at forward/backward rapidity is actually larger ..." - this is also not needed. 

- L204: Υ(1S + 2S + 3S) and Υ(2S + 3S) -> Υ(1S + 2S + 3S) and Υ(2S + 3S) yields

- L206: Figure 5a -> Fig. 5(a).

- L206-207: , while the STAR data are also compared to the CGC+NRQCD calculations -> . Figure 5(b) presents the STAR data compared to the CGC+NRQCD calculations ... 

- L208: As can be seen the CEM -> As can be seen, the CEM

- L208: Υ(1S) yield -> Υ(1S) cross section

- L210: remove "Similarly," - there are different models

- 210: Figure 6a -> Fig. 6(a)

- 211: Color Singlet Model -> CSM (you already defined it)

- L212: On the other hand, the Figure 6b -> Figure 6(b)

- L213: Again, the rapidity -> The rapidity

- L214: CEM model -> the CEM model

- L215: "are overestimated by direct CGC+NRQCD calculations" - At forward/backward y, Upsilon(3S) is consistent with CGC+NRQCD and Upsilon (2S) is away ~1sigma from the CGC+NRQCD calculation (?)

- L216: Finally the -> Finally, the

- L216: Υ production -> the Υ production

- L218: formula below -> formula (3). 

Explain all the components below the equation.

- L219: Then for -> For

- L220: but if there are more partons involved, then n > 4 -> and if there are more partons involved n > 4.

- L220: Morover, the Υ mesons are produced in hard -> The b\bar{b} pairs are produced in hard

- L221: but the bound state formation involves soft interactions -> but the Υ bound state  formation involves soft processes

- L222: shown in Figure 7 -> and is shown in Fig. 7.

- L226: remove "The cross section ratios were ... reconstruction efficiencies."

- L226: STAR data -> The cross section ratios

- L227: Figure 8a -> Fig. 8(a)

- L227: move references to the end

- L228: average ratios -> average Upsilon states ratios

- L229: uncertainty is indicated as a small box on the right sight of the Figure -> uncertainties are indicated as boxes on the right side of the figure. 

- L230-231: It can be noted that STAR data are below the fits, but this is not very significant as the deviation is -> The STAR data were not included in the fits and they are below with significance of 

- L233: Figure 8b -> Fig. 8(b)

- L235: "The decrease of the ratios with multiplicity" - I don't see decreasing trend in data. 

Reformulate that it's clear that you mean that the comover model expects such a decrease.

- L236: Linear fits are performed in order to investigate the possible dependence -> In order to investigate the N_ch dependence of the ratios, linear fits are performed. 

- L236-237: remove " while the 1σ ... drawn (dashed lines)"

- Expand the description a bit, saying that here you extract the Upsilon signal using the same method of fitting the inv. mass distributions as described before, in different N_ch bins, etc. 

- L241: Upsilon/<Upsilon> -> N_Upsilon/<N_Upsilon>

- L 243: add the value of the mean N_ch, it should be also discussed earlier.

- L247: "the common trend of strong increase" - it would be good to quantify how strong this increase is for the Upsilon result.  

- L249: The Figure 9b -> Figure 9(b)

- L249-252: on the plot you show STAR results for both Upsilon(1S+2S+3S) and for Upsilon(1S),  but you don't write in the text for which Upsilon state(s) the calculations are. Also, how is the feed-down treated ?

- L254: STAR presents a presents first measurement of ... -> We present a first measurement of p_T and y differential production cross section of \Upsilon(1S), \Upsilon(2S) and \Upsilon(3S) in p+p collisions at \sqrt{s} = 200 GeV.

- L255: remove "The data allowed separation of Υ(2S) and Υ(3S) states. " - this already the previous sentence says. 

Instead add: "The results are compared to different model predictions."

- L255: The Υ(1S) differential cross sections -> \Upsilon(1S) spectra

- L265: "inclusive CEM" - do you mean CEM for inclusive Upsilon(1S) production ?

- L257: the separated spectra for each state ->  spectra for each state

- L258: spectrum is also underestimated -> spectrum is underestimated

- L259: An xT dependence was also obtained in order to investigate possible xT scaling for Υ states. No scaling -> An xT scaling of Υ states is also investigated and no scaling

- L259: was observed -> is observed

- L261-262: Cross section ratios were also measured and found to be below the average measured by other experiments, but the difference is less than 1.74σ for Υ(2S)/Υ(1S) and even lower for Υ(3S)/Υ(1S) -> Cross section ratios for different Υ states are consistent within 2\sigma with the world average. 

- L262-264:  Charge particle multiplicity dependence of cross section ratios was also investigated. These results do not indicate a strong dependence on multiplicity within large uncertainties, which suggest -> Charge particle multiplicity dependence of the cross section ratios do not show strong dependence on the multiplicity within the current uncertainties. This suggests 

- L265: The normalized Υ yield Υ /⟨Υ⟩ was also measured vs. normalized multiplicity Nch / ⟨Nch⟩ . The STAR Υ(1S) results for pT > 4 GeV/c are following the same trend -> The normalized Υ yield Υ(1S)/<Υ(1S)> vs. normalized multiplicity Nch / ⟨Nch⟩ for Υ(1S) pT > 4 GeV/c follows the same increasing trend 

- L267: PYTHIA -> PYTHIA 8

- L273-274: "as well as overall particle production models." - this is not clear

- L274: Further, more -> More

- L274: of Υ production -> of the Υ production

- L275-276: These will be possible with the data collected by STAR during 2017 run, which provided 340 pb−1 of integrated luminosity. Even more data will be available after planned 2023 run. -> I would remove this. First, one may ask why then 2017 data is not  used here, it's already quite an old dataset. Second, there's no p+p in 2023, and 2024 in p+p at 200 GeV but we don't know yet how much. 

- In some places you have "'sigma", in some "sigma^Upsilon" - please unify.

- All plots with ratios: you don't need to double the common x axis, you can move a ratio panel directly under a cross section panel and have x-axis description only in the ratio plot. 

- In the figure caption, you don't need to mention colours, it's enough to have and mention different types of markers/lines/areas. 

- @ 500 GeV -> \sqrt{s} = 500 GeV.  

- Fig. 1: 

   - use different symbols for unlike and like sign distributions. In the text, refer rather to a symbol's or line's shape than its color.

   - I suggest making a common x-axis for all the three plots.

  - What chi2/ndof and K-S test values on the most upper plots should tell here ? It's not really described in the text, so I wouldn't make the figure too busy and remove the numbers. 

  - Top most panel: remove lines from around the legend. 

     - 10 [GeV/c] -> 10 GeV/c. 

      -  Why do you give numbers specifically for Upsilon(1S) and Upsilon(2S+3S) ?

    - y axis titles for pull plots are too small. Also, the pull distributions are not described anywhere - in this case you should remove them.

- Fig. 2: 

   - y axis title: remove "[1]"

   - there is no information on the system and energy + STAR

   - p_T^MC is not explained anywhere.

   - left plot: blue, green and brown and very close to each other, I would prose to plot only the brown distribution.

   - right plot: markers and lines are thinner on this plot than on the 2a.

- Fig.3: 

   - the caption suggests that you show only already published results: "Integrated cross section of Υ(1S + 2S + 3S) measured by STAR [39] "

   -  data measured by other experimentas ->  other experimental results

- Fig. 4 

   - caption: Invariant cross section -> p_T differential cross section.

   (same as above) -> Move the description of markers for different Upsilon states to the end of the caption. 

   - right: decrease max of the y axis

- Fig. 5,6b: use different shaded areas 

- Fig 5, 6. caption: light blue -> blue

- Fig. 7: 

   - this plot is busy and the markers are too small. I would suggest combining ATLAS and CMS results for the same Upsilon state, mark them as "LHC" and use the same markers. Remove STAR Upsilon(1S+2S+3S) and Upsilon(2S+3S) results, they don't bring anything here.

Then if it's still too busy, you can consider separating different Upsilon states into two left-right adjusting plots. I would also combine the sys. unc., they cannot be distinguished here. 

   -  x-axis title: remove "[1]"

- Fig. 8: 

   - the caption is too long, please make it shorter. 

   - caption: on charged particle multiplicity T ofMult -> on charged particle multiplicity

   - a: You repeat the same in the STAR legends. You can move STAR and |y| < 1 above and then leave the description of the Upsilon ratios in the legend. And you don't have information that STAR data are p+p at 500 GeV

   - b: move "|y| < 1" outside of the legend, e.g. like in Fig. 9

   - b: add information about N_ch shift in the legend.  

   - b: the figure is too busy - I would remove the 1\sigma line. You can try to replace the 1sigma unc. with a light shaded area. 

- Fig. 9

   -  x-axis title: N_ch/<N_ch> -> (dN_ch^MB/deta) / <(dN_ch^MB/deta)>

   - a: It's a bit busy, I would suggest making two figures, one with pT > 0 and the other with pT > 4 GeV/c results. It should make both the presentation and the description of the results in the text more clear. You can make one figure with two left-right adjusted panels.

   - b: make the percolation model's line thicker 

On Sun, Aug 21, 2022 at 9:47 PM Sooraj Radhakrishnan <skradhakrishnan AT lbl.gov> wrote:

Hi Leszek,

   Thanks for preparing this well written and clear analysis note and for the paper draft. Sorry for the delay in sending the comments. Please find some comments/questions from me on the analysis note below:

p 12: Do you know what goes into the definition of 'flag' variable? How are the flag > 1000 and flag < 0 tracks defined? Is it something commonly used in p+p analyses?

p 12: would be good to include the definition of TofMatchFlag

p 12: the drop in TofMult vs BBC rate is attributed to occupancy. But the refmult values at these BBC rates are small, comparable to very peripheral Au+Au collisions. In Au+Au, the occupancy effects show up in central events. Is there another reason for the drop in TofMult?

p 12: This may not be the best way to evaluate if there is impact. The trigger requirements will boost number of events with Y. So a better estimate would be, with the production rates, whats the probability to have an Y in your sample after the selection cuts

Table 2.4: Is there a reason to reduce the nHits cut for TofMult definition?

p14: Is the R_SMD cut used in other electron analyses as well?

Fig 2.7,2.8: In all pT bins, the points around the 1S and 2S peaks fluctuate above the fits. Also the right side of the peak is below the fit in several cases. Is this a systematic effect, on background evaluation or signal shape? Would this have an impact on yield ratios? 

p17: Is the PYTHIA for the combinatorial background without any detector effects? Will there be any impact from the efficiency or resolution? Are the same electron kinematic cuts applied on PYTHIA as the data?

p19: Are the uncertainties on the fit parameters considered when doing the purity and efficiency corrections for the signal extraction?

p26: Section reference missing

p34: Could you give some details/links to the TOF embedding. Remember this was one part that went through a few revisions 

Fig.2.27: Sorry, I am a bit confused here. The analysis is using the triggered sample. The red distribution is the multiplicity distribution for Y events.  Are the final ratios relative to the red or the blue (MB) distribution?

Sec 2.6.1: As pointed at above, there is a fluctuation of the data points above the fit near the peak and balancing of it on the right side through fluctuations down, This small uncertainty could be coincidental 

Sec 2.6.4 This is much smaller than the 5% uncertainty typically quoted for tracking efficiency. Is this the value commonly used in p+p analyses?

Sec 2.6.14: Is this variation of the prior distribution in the unfolding? What is the variation studied here?

p 47: figure references missing

p 48: figure references missing

Sec 3.1.6 What physics do we learn from the xT scaling? Could you add a sentence or two? 

thanks

Sooraj

On Fri, Aug 12, 2022 at 2:12 PM Barbara Trzeciak via Star-hf-l <star-hf-l AT lists.bnl.gov> wrote:

Hi Leszek,

Sorry for the late reply.

Please find my comments/questions to the Analysis Note below.

Also, do you have checks on distributions that Rongrong asked ?

Cheers,

Barbara

--- Comments on the Analysis Note ----

- Sec 2.3.2: it would be good to add nSigmaE (and some projections) and E/p plots to see where your cut values sit w.r.t. to the distributions. 

- Sec. 2.3.3: it's not clear from this section that you form a pair and then one electron candidate is required to satisfy the trigger conditions (you only write that at least one track from each event has to satisfy DSM adc > 18 condition) and the other is the partner electrons for which you require pT > 1 GeV. Please make it more clear.

- Signal extraction: 

   - it would be good if you add an appendix (or include a link) to all the invariant mass fits, in all the pT, y and multiplicity bins.

   - You should mention somewhere and define the pull distributions that you also have. 

   - Correlated bkg: how did you define the fit function ?

- Sec. 2.5.1

   - Missing reference to the embedding section

   - Table 2.7: are those cuts only for the partner electron or for both electrons in a pair ? Are the track quality cuts the same as before used here ? 

   - It would be good to add the invariant mass distribution of unlike and like-sign pairs to judge the purity of the sample.

- Sec. 2.5.2

   - You assume a Gaussian shape of the y distribution ? I assume so from the first term of Eq. 2.5 (that I guess is for rapidity), but it's not explained in the text.

   - The fit was used to extrapolate the obtained values - do you mean the log fit from the previous sentence shown in FIg. 2.15b ? It's for Upsilon (1S), how do you get extrapolated values of the other states ? Also, can we determine the slope parameters with such precision and don't they have some uncertainties ?

- Sec. 2.5.3

   - Do you calculate efficiencies as a function of MC or reconstructed electron (Upsilon)  pT ? Please clarify in the note.

   - Why do you need single electron efficiencies if you later calculate efficiencies directly for different Upsilon states ?

- Sec. 2.5.4

   - Why do you start here from the level of L0 cut ? Also, does L0 include the pT cut for the partner electron ? Please clarify.

   - Explain how you calculate acceptance. 

   - nSigmaE cut is calculated from data for single electrons. Please explain here how you obtain nSigmaE efficiency for Upsilon. And do you consider rapidity dependence ?

   - Please also explain in the text each efficiency contribution that you present on the plots. 

   -  Most of the efficiencies are calculated based on the embedding. There should be added comparison of distributions from embedding and data (nFitPts, dca, E/p, Adc ...) so that one can judge how well the simulation described the data. Have you e.g. compare E/p efficiency from data and embedding ? I don't see any sys. unc. assigned to E/p.

   - Differences between efficiencies for different Upsilon states are quite big. Is it expected, why the trigger efficiency would differ so much ? It's hard to judge difference for other sources as they already contain L0 efficiency. Could you please add efficiencies for single sources, i.e. L0, Acc, Track etc. (not L0*Acc ... ) and compare them between Upsilon states.

- sec. 2.5.5

   - Is the a parameter the same for the whole pT range ? I think there can be some pT dependence of it. Is the chi^2 minimization done for the pT-integrated signal or vs J/psi pT, also what is the red line in Fig. 2.20b ?

- sec. 2.5.7

   - Do you assign any uncertainty related to the assumption of the power law shape ? 

- sec. 2.5.8

   - How did you determine 4 interactions for the unfolding and what did you use as a prior ? 

   - Do you vary the prior shape as part of your systematic unc. ? In your unfolded range you go beyond what is measured and therefore you're probably sensitive to the underlying prior shape, so you depend on Monte Carlo simulations here. 

   - Fig. 2.27a: what is the black distribution ?

- sec. 2.6.1

   - The fit also includes fit to the uncorrelated and correlated backgrounds which influence the signal extraction. It would be good to have some sys. unc. related to these fit parts of the fit.

- sec. 2.6.6

    - It's not explain how the 3% shift is taken into account and how the final unc. is estimated ?

- sec. 2.6.10

   - Could you please provide more detail here. It's not clear to what exactly you refer from Ref. 3.

- sec. 2.6.12

   - Is the reconstruction efficiency applied before or after unfolding ? 

   - The efficiency has quite a large uncertainty in the last TofMult bin. Is it due to low statistics in the embedding ? If so, isn't it a problem for creating a response matrix ?

- sec. 2.6.14

   - Which distribution is fitted with NBD ? Would be good to add these fits.

- sec. 2.6.15

   - What is the default setting ?

- sec. 2.6.16

   - What is "Fit" in the tables. Is it signal extraction unc. ? Please make it more descriptive. 

- sec. 3.1.2

   - How do you obtain the 2S+3S signal, i.e. at which level do you add the signals: at the raw level or after applying corrections ? If at the raw level, how do you calculate the combined efficiency ?

- sec. 3.1.3

   - "The cross section for the 1 < y < −0.5 and 0.5 < y < 1 is added together in 0.5 < |y| < 1 and reflected symmetrically.": I'm not sure if I understand - do you perform fits separately for 1 < y < −0.5 and 0.5 < y < 1, calculate cross sections and then add the cross sections or you extract the yield by adding 1 < y < −0.5 and 0.5 < y < 1 bins and then calculate one cross section ? It sounds like the former but I think the latter makes more sense. 

   - It would be good to add a plot of efficiency vs rapidity for each Upsilon state - in sec. 2.5.4. It will be easier to compare values in the two rapidity ranges. Could you also compare |y| < 0.5 and 0.5 < |y| < 1 efficiencies for single sources, i.e. L0, Acc, Track etc. (not L0*Acc ... ).

   - Figure numbers are missing in the result sections. 

- sec. 3.1.4

   - Do you correct for BR ?

   - "The STAR data are more consistent with the values up to pT = 6 GeV/c" - this is not clear to me

- sec. 3.1.5

   - " A pT dependence is observed and is indicated in the shift of ..." - you claim here a pT dependence, how many sigmas from the linear fit and from the data point for pT > 0 GeV/c, this last red point is ?

   - "This gives a hint of collective effects, which may be present at high multiplicity in p + p collisions" - what exactly points to collective effects ?

   - Some figures, like 3.7 right and 3.12 seem not to be discussed in the text. 

  

- It would be good if you added to the AN the most recent checks and discussions that we had at the PWG meetings.

On Fri, Aug 12, 2022 at 5:51 AM Yi Yang via Star-hf-l <star-hf-l AT lists.bnl.gov> wrote:

Dea Leszek,

(I added this to the HP list, probably we can discuss it there.) 

Sorry again for the late response. 

I have some comments/questions on your analysis note and I will send out my comments on your paper draft in a separate email. 

 

- Abstract: remove all "J/psi" related things. 

- p12: Any references for the "flag" information or definition? 

- p12: Should include the eta range in the second paragraph.   

- p13: Move Figure 24 to Figure 23 (since the current Fig. 23 was mentioned later). 

- p14: You mentioned several variables: R_SMD, E_TOW/E_CLU, E_CLU/p, ... how did you choose these cut values? Can you show some studies or references? 

- p17: The fitting of the Upsilon signals. Since STAR doesn't have a good resolution to separate Upsilon states, it is very tricky to fit the signal. You can take a look at how ATLAS did (they have similar mass separation power), just for your reference.  https://arxiv.org/pdf/1211.7255.pdf  (Section IV C.)

- p19: It is still strange to me that you do a bin counting from a range and then move the contaminations from other states from the fit. Why do you just integrate from the fit? (I understand you use this as the systematic, but the procedure is a bit strange to me.) 

- p23: Figure 2.10 (b): why the uncertainties on 2S and 3S only have up-forward or down-forward uncertainty? 

- Could you please provide the full function used in your fit? 

- All mass plots (especially for the plots used in paper), I would think the style can be improved a bit: all the font sizes are too small, the bottom panels can move up and combine to the top panel (share the same x-axis). Since you are using unbinned-likelihood fit, you can make the plots with coarser binning. Difficult to read the label on the y-axis in the bottom panels. 

 - p26: First paragraph. Section ??

 - p26: Table 2.7: invariant mass cut < 0.04 GeV/c^2 --> Should it be 0.3 GeV/c^2?  I think other heavy-flavor electron analyses used 0.2 GeV/c^2. Can you add the mass plot of your photonic electrons in the note? 

 - p29: Electron efficiency:  

          - Figure 2.16: there is an "acceptance" in the electron efficiency, can you define it? Naively, I thought the electron efficiency should only be calculated inside the TPC acceptance. 

          - Do you expect the efficiencies for electrons and positrons to be different? If not, why don't you combine them? 

 - p29: Upsilon efficiency: 

          - How do you define acceptance? Can you add it in the note? 

 - p30: The main concern I have is in the result of cross-section vs y and I remember we discussed intensively and the reason is that you have similar raw yields for 2S and 3S in |y| < 0.5 and 0.5 < |y| < 1, but the efficiencies has a factor of 2 difference (Fig. 2.17 (b) and (c). Do you know why L0 efficiencies are different in two rapidity ranges? I remember Ziyue and others found that the n_sigma_e has some dependency on eta. Could you please also check it on your dataset? 

 - p31: Did you also consider "shifting" the mean of the track resolution?   

 - p39: Systematics: Please add more details of your systematic uncertainty study. It would be good to have all the plots included. So far, you only have a short description and the final number for each source. 

 - p45: Chapter 3: Lots of links to Figures or Sections are missing, for example p47, Figure ?? and Figure ?? in the second paragraph. 

 - p50: Figure 3.5 (b): I am still worrying about the "dip" in 3S state, it seems that there is a ~3 sigma effect from "flat". We probably really need to understand it before we release this result, since it might cause lots of discussion from the theorists' side. (I am not saying it is wrong, but we will need some understanding and explanations. 

 - Similar comments on the results plots, the style probably can be improved. (But this can be done in the GPC stage.)

 - Figure 3.4 and 3.5: I still don't understand why we need to mirror the points to the negative rapidity. It won't give us any more information, you can just simply change the x-axis to |y| and plot to data points. 

 - You can make all your plots much larger. 

 - p56: NLO [?]

Cheers,

Yi

+++++++++++++++++++++++++++++++++++++++++++++++++++
Yi Yang, Associate Professor
Department of Physics
National Cheng Kung University
Tainan, 701 Taiwan
E-Mail: yiyang AT ncku.edu.tw
Tel: +886-6-2757575 ext.65237
Fax: +886-6-2747995
Group Web: http://phys.ncku.edu.tw/~yiyang
+++++++++++++++++++++++++++++++++++++++++++++++++++

On Wed, Feb 16, 2022 at 11:03 AM Leszek Kosarzewski via Star-hf-l <star-hf-l AT lists.bnl.gov> wrote:

Dear All

As I presented today, the Upsilon states in p+p 500 GeV paper is ready for review.

Paper page:

https://drupal.star.bnl.gov/STAR/blog/lkosarz/upsilon-production-pp-500-gev

Paper:

https://drupal.star.bnl.gov/STAR/system/files/Upsilon500_Paper_LK_v6.pdf

Technical notes:

https://drupal.star.bnl.gov/STAR/system/files/Upsilon500_TechNotes_LK.pdf

I also updated the presentation to answer today's questions (see slides 24-29):

https://drupal.star.bnl.gov/STAR/system/files/Upsilon_HF_LK_2022_2_15.pdf

The tracking efficiency uncertainty is actually correct. It affects the shape of N_ch distribution and also the shape of Upsilon N_ch distribution through unfolding correction. For Upsilons also the input distribution is affected by the efficiency from embedding and signal extraction. In the simulation for unfolding correction the uncertainty is estimated by changing the efficiency by +/-5%. For the Upsilon signal, the nFitPts is changed by +/-2 in embedding and data. The cumulative effect of all of that is large for the last Nch bin. Also if the shapes are changed this means that the effect on Nch/<Nch> will not cancel out enirely, though the effect is lower than the input +/-5%. In addition the bins are fixed with default <Nch>. The J/psi paper shows similar values for these uncertainties.

The 4Cx uncertainty also affects the data in this way. Upsilons are affected by the change in both Upsilon and min-bias Nch distributions, so again the effect is larger on Upsilons.

I also checked the eta and y distributions and efficiencies. There is a dip for triggering track, but this is not shown in y distribution of Upsilon candidates.

Best regards, Leszek

_______________________________________________
Star-hf-l mailing list
Star-hf-l AT lists.bnl.gov
https://lists.bnl.gov/mailman/listinfo/star-hf-l

_______________________________________________
Star-hf-l mailing list
Star-hf-l AT lists.bnl.gov
https://lists.bnl.gov/mailman/listinfo/star-hf-l

_______________________________________________
Star-hf-l mailing list
Star-hf-l AT lists.bnl.gov
https://lists.bnl.gov/mailman/listinfo/star-hf-l

--

Sooraj Radhakrishnan

Research Scientist,

Department of Physics

Kent State University

Kent, OH 44243

Physicist Postdoctoral Affiliate

Nuclear Science Division
Lawrence Berkeley National Lab
MS70R0319, One Cyclotron Road

Berkeley, CA 94720

Ph: 510-495-2473

Email: skradhakrishnan AT lbl.gov