STAR HardProbes PWG

["张炜" <wzhang AT m.scnu.edu.cn>]

Hi Yi and Isaac,

Thank you for the nice comments.

for Yi's comments:

p2.

I've changed the 'PA name' to 'PA representative name.' After HP 2024, I will submit a paper proposal, and all the PAs will be listed at that time.

p8.

Yes, your understanding is correct. In the formula for additional momentum smearing, the parameter 'b' in the numerator comes from the 'b' contained in σembedded\sigma_{\text{embedded}}, they are same;

p16.

I don't know the exact reason at the moment, but I have listed the raw signal counts and the corresponding pair efficiency when using the default and wide nsigmae cuts on slide 24 (backup).

Also，I add a slide to summarize the physics message of this analysis on slides 25,26.

for Isaac's comments:

p6.

The Vz range depends on the centrality definition. In fact, for the Au+Au 27 GeV centrality definition, they used |Vz| < 70 cm, while for 19.6, 17.3, and 14.6 GeV, it's |Vz| < 145 cm. However, when I started the analysis for 19.6 and 14.6 GeV, I wasn't aware of the exact value, so I just looked at the Vz distribution from the MB trigger and, in order to maximize statistics, I chose a 150 cm cut. But I think for publication, it should be consistent with the centrality definition.

When performing the extrapolation, we fitted the J/ψ pTp_T​ distribution for 19.6 GeV and found that 99.7584% of J/ψ are below 4 GeV. Therefore, we can use this ratio to estimate how many J/ψ have pT>0p_T > 0 GeV. For 17.3 GeV, I used the results from 19.6 GeV when performing the extrapolation. I updated the relevant plot on page 27 of the slides.

p12.

The black dashed line here represents the envelope of the largest variations in the systematic uncertainties. However, we did not ultimately use this method; instead, we used the RMS of this set of data as the systematic uncertainty for each bin.

p13.

The selection criteria for these two plots are different because when calculating the nsigmae cut efficiency, it means we cannot use any nsigmae-related cuts. Similarly, when calculating the TOF matching efficiency, we shouldn't use TOF-related cuts to select electron candidates.

p19.

Thank you for the correction.

 

 Once again, thank you very much for your excellent comments. If you have any further feedback, please feel free to let me know.

Best,

Wei

------------------ Original ------------------

From:  "Mooney, Isaac"<isaac.mooney AT yale.edu>;

Date:  Tue, Sep 17, 2024 04:09 AM

To:  "STAR HardProbes PWG"<star-hp-l AT lists.bnl.gov>;

Cc:  "Nihar Sahoo"<nihar AT rcf.rhic.bnl.gov>; "Yi Yang"<yiyang AT ncku.edu.tw>;

Subject:  Re: [[Star-hp-l] ] Preliminary request for J/ψ analysis at Au+Au17.3GeV

 

Hi Wei,

I also only have some minor questions on the preliminary request (see below).

Thanks,

Isaac

6.

How was the vertex z range determined? I notice that for the 27 GeV, the z vertex range was much smaller, while for the 19.6 and 14.6 (150 cm) it's slightly larger than this 145 cm.

I see that the number of accepted events is about half that of the 14.6 GeV for example. Is this why the pT > 2 GeV bin is not included for the 17.3 GeV dataset? Because you run out of statistics? Is the upper cutoff for the pT integration then 2 GeV for e.g. the Fig. 3 values? Does it affect the result at all if you include whatever small counts you get above 2 GeV? I assume not, just wondering.

12. Is the black dashed line the maximum envelope of the systematic variations in each bin, or the total systematic uncertainty in the bin? Or are these two things the same (i.e. you're using the maximum envelope as the uncertainty?

13. Maybe this is a silly question, but why does the S/B ratio here say 80.97 for the 0.02 pair mass maximum, while on s. 15 it says 69.62?

19.

You say R_AA increases with increasing pT, but this isn't a pT dependent plot. I think this bullet was meant to refer to the previous figure. The caption also refers to pT when it should say Npart.

The legend has the wrong marker for 17.3 GeV.

On Sep 14, 2024, at 06:15, Yi Yang <yiyang429 AT gate.sinica.edu.tw> wrote:

Hi Wei,

Thanks a lot for the slides for the preliminary request.

I only have some very minor comments and questions.

 - p2: Are you the only PA for this analysis? It would be good if you can list all.

 - p8: In the additional smearing, there are 3 parameters: a, a', and b, if I understand correctly, the smearing parameter from embedding is a and b, then you add an additional smearing for comparing to data. Is parameter "b" the same for embedding and additional smearing?

 - p16: the systematic from n_sigma_e for 20-40% is much larger than other centrality bins, do you know why?

 - It would be good if you can add a slide to summarize the physics message of this analysis for others who will present this result in the future.

Cheers,

Yi

+++++++++++++++++++++++++++++++++++++++++++++++++++
Yi Yang, Research Fellow
Institute of Physics, Academia Sinica
E-Mail: yiyang429 AT gate.sinica.edu.tw
Tel: +886-2-2789-6709
+++++++++++++++++++++++++++++++++++++++++++++++++++
-----Original message-----
From:张炜<wzhang AT m.scnu.edu.cn>
To:Mooney, Isaac<isaac.mooney AT yale.edu>,Nihar Sahoo<nihar AT rcf.rhic.bnl.gov>,Yi Yang<yiyang AT ncku.edu.tw>,STAR HardProbes PWG<star-hp-l AT lists.bnl.gov>
Date: Tue, 03 Sep 2024 11:13:31
Subject: [[Star-hp-l] ] Preliminary request for J/ψ analysis at Au+Au17.3GeV

Hello Isaac, Nihar, and Yi,

I hope this email finds you well.

Here are my preliminary request slides for Hard Probes 2024: https://drupal.star.bnl.gov/STAR/system/files/Prelim_Request_17p3.pdf

Please let me know if there are any specific areas that need adjustment or further detail. I am more than happy to make revisions based on your guidance.

Thank you for your time and assistance.

Best regards,
Wei