STAR Correlations and Fluctuations PWG

[Dylan Neff <dneffucla AT gmail.com>]

  Hi Takafumi,

Thanks for the helpful feedback and sorry for the delayed response! I've uploaded the edited slides (v8). I believe I've addressed each of your suggestions but please let me know if I missed any or you have further suggestions on the changes I've made.

s3: The nsigma proton for 27 GeV was compressed, and all nsigma proton cuts in this data set were scaled by a factor of 2 to compensate. I wasn't around when the data was being produced but have uploaded my rough QA plots showing the nsigma proton distribution from my data for 27 and 19 GeV (red histogram is after all of my cuts have been made).

s7: I take 1 track from each event. I rephrased the text and put three tracks (one from each raw event) in the mixed event cartoon. I actually do split into vz bins but forgot to add it to the text, thanks for catching that!

s12: Annihilation would lead to a repulsive effect if both protons and anti-protons were counted. I hope to discuss possible sources of this repulsive signal in the future but I believe momentum conservation could also effectively produce a repulsive effect. In addition the excluded volume effect has shown to produce a repulsive effect in the MUSIC+FIST model (purple points all lower than blue). 

Yes, v2 should produce a clustering type effect. When I looked into this in the past I found that the  mixed events could partially wash out the v2 signal. In simulation if the reaction plane was used the v2 signal was almost entirely divided out (only limited by the resolution of our event plan binning, we use 20 event plane bins). Using the event plane angle with realistic resolutions, the clustering effect was only partially washed out with the mixed events. I plan to quantify the effect of v2 as I wrap up this analysis but it should be a small clustering signal on top of the repulsive signal that was observed (especially in the central events shown in this talk).

Thanks,
Dylan Neff

On Sun, Nov 27, 2022 at 3:29 PM Takafumi Niida <niida AT bnl.gov> wrote:

Dear Dylan,

Nice slides. Since the conference starts soon, I am sending my comments here to the version: https://drupal.star.bnl.gov/STAR/system/files/Neff_CPOD_2022_v7.pdf

general: It would be nice if you can put STAR logo in each slide or at least small text on footer, so that people can easily know this talk is from STAR.

s3:

- In the right table, “27GeV” put space between them. Could you remind me why you have stricter cut only for 27 GeV?

- In the last row of right table, add unit for pT or p at least once somewhere and same to m^2.

- "Centrality Definition: refmult3” Looking at the following slides, you don’t use the word “refmult3”, right? I so, just remove “refmult3” here. The definition written below is enough.

- "Corrections Implemented” What you list here are event cuts and good run selection, not “corrections”. I would rephrase it.

s4:

- sign of first -> sign of a first

s7: 

- Do you take one track from one event when making mixed event? Can you make it clear?

- For your future study, you may want to consider Vz for mixing because your acceptance, therefore the average number of particles, depend on Vz. If you take one track per event, it may not matter though.

s10:

- In 1st bullet, please define SD, i.e., “standard deviation (SD)”, as you use it in the last sentence.

- Add “Au+Au” and proton pT/rapidity ranges somewhere inside the figure. Also add small texts like “statistical uncertainty only”

- You may want to mention that the efficiency effect would be largely canceled by taking the ratio of real and mix.

s12: 

- 1fm -> 1 fm

- Same comment for the plot (add system/kinematic info.)

- Can you provide any example of physics which leads to “repulsion”? I know you call it “repulsion” based on your simulation in backup slide 16. There is an impression that suddenly “repulsion” appears without any explanation. Could it be annihilation?

- If we have strong v2, more particles are emitted into the reaction plane angle. How does your observable look? Something similar to the right plot of slide 11? Depending on how you make Mix, such a v2 effect can be or cannot be canceled?

- For references, two of them are published, so please put journal number instead of arXiv number. Also, please put at least one author name (with “et al” if it’s not single author paper).

s13:

- put space between number and “GeV”, e.g. 19GeV -> 19 GeV

- Add proton kinematic info. inside one of panel, and also add “Au+Au” and small texts “statistical uncertainty only” somewhere

Best regards,

Takafumi

On Nov 21, 2022, at 16:00, Dylan Neff via Star-cf-l <star-cf-l AT lists.bnl.gov> wrote:

Hi Xiaofeng,

 

Thanks for your feedback!

1. I added a slide after 5 explaining the resampling
2. I don’t have systematics and probably won’t quite be able to get them finished before the conference so I removed slide 13. I also don’t have the systematics for the other slides (10, 12, 13), is this ok? From my previous analyses I wouldn’t expect the systematics to be much larger than the statistical errors.

 

 

Thanks,

Dylan Neff

 

From: Xiaofeng Luo via Star-cf-l
Sent: Monday, November 21, 2022 8:11 AM
To: webmaster--- via Star-cf-l
Subject: Re: [Star-cf-l] STAR presentation by Dylan Neff for CPOD 2022 submitted for review

 

Hi Dylan,

    Please find my suggestions to your CPOD presentation. 

    1. After slide 5, you may add one slide to explain  : what is more samples per events.  Why use 72 samples in the following slides, 
        which is used in your data analysis.    
    2. Slide 13, do you have systematic uncertainties on the STAR data ?  If only statistical errors, I would suggest to not showing the data points. 
       
Thank you, 
Best Regards,
Xiaofeng

On 2022/11/21 15:45, webmaster--- via Star-cf-l wrote:

Dear star-cf-l AT lists.bnl.gov members,

Dylan Neff (dneff AT physics.ucla.edu) has submitted a material for a review,  

please have a look:

https://drupal.star.bnl.gov/STAR/node/61796

Deadline: 2022-11-28

---

If you have any problems with the review process, please contact  

webmaster AT www.star.bnl.gov

_______________________________________________

Star-cf-l mailing list

Star-cf-l AT lists.bnl.gov

https://lists.bnl.gov/mailman/listinfo/star-cf-l

-- 

Xiaofeng Luo

Professor of Physics

College of Physical Science and Technology

Central China Normal University

Luoyu Road 152, Wuhan China

Office Phone #: +86-27-67867500

 

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