STAR Correlations and Fluctuations PWG

[Bhosale Sneha <bhosales AT staff.elte.hu>]

Dear Nu,

Thank you so much for the email. Since my talk is on 5th of November 2024(Tuesday) I mostly removed the things you asked for and here are my responses/explanation for you comments;

 1) A slide could be added to explain the physics meaning but given that now the talk is very close (Tuesday), I cannot do anything else but just remove these mentions. I do think the concept is important but it would probably need discussions within the PWG how the explanatory slides should look like, so for the sake of time, I removed these statements.

 2) For the first point (i), "Lévy-scale R" is the size parameter of the Lévy distribution, meaning the size of the source. For the second point (ii): for all these fits, chi^2/NDF is approximately the same, around 1. It is however not a good number to estimate goodness-of-fit, as for large NDF (number of degrees of freedom) values very small changes in chi^2 can lead to large changes in probability. Thus, it is more important to show chi^2, but even more importantly, the probability (p-value or confidence level). Nevertheless, I now wrote on the slide that chi^2/NDF is approximately 1 for all fits.

 Actually, the number of parameters differs just by one, alpha is the only additional parameters. More accurate description can be claimed because of the difference in the goodness-of-fit. But for the sake of reaching a good consensus, I removed this wording.

 The updated version is now available here for your: (version 3)    https://drupal.star.bnl.gov/STAR/node/69661

 Thank you again. 

 Best regards,
Sneha

---

From: Nu Xu <nxu AT lbl.gov>
Sent: Saturday, November 2, 2024 7:46 AM
To: Bhosale Sneha <bhosales AT staff.elte.hu>
Cc: Nu Xu <nxu AT lbl.gov>; STAR Correlations and Fluctuations PWG <star-cf-l AT lists.bnl.gov>
Subject: Re: [[Star-cf-l] ] WPCF 2024 talk

 

Dear Sneha,

Thanks for the updated presentation. I do have trouble with some claims shown in the present slides:

1) The term Levy Walk mentioned in slides 6, 13, 15, and 17.
We throw the term to audiences without explanations, it is very confusion. For this talk if the concept is needed, then provide the physics meaning. It it is not needed for this talk, take them all out of the presentation.

2) slide 14: (i) What does it mean by “Levy-scaled R”? (ii) right two plots: are these the chi^2/per degree of freedom? If it is, please note them so, for example, chi^2/pdf.
If I understand, there are many more parameters in the so-called Levy-fit, including epsilon_o, epsilon_s, epsilon_l?

A fit with many more parameters, in this case is the Levy-fit, can we really claim “… more accurate shape and size” shown on slide 5?

Best regards,
Nu

> On Nov 1, 2024, at 3:24 AM, Bhosale Sneha <bhosales AT staff.elte.hu> wrote:
>
> Dear Nu,
>
> I wanted to follow up on my response to your helpful feedback on my presentation. I have incorporated the suggested changes and provided explanations where needed, including adjustments on slides 10, 11, 14, and 15, along with the reference addition. My responses to your suggestions can be found in below email.
>
> The updated version is now available here for your review: https://drupal.star.bnl.gov/STAR/node/69661
>
> Thank you once again for your valuable insights, and I look forward to any further suggestions you may have.
>
> Best regards,
> Sneha
>
>
>
> Get Outlook for AndroidFrom: star-cf-l-request AT lists.bnl.gov <star-cf-l-request AT lists.bnl.gov> on behalf of Bhosale Sneha <bhosales AT staff.elte.hu>
> Sent: Wednesday, October 30, 2024 4:58:25 PM
> To: STAR Correlations and Fluctuations PWG <star-cf-l AT lists.bnl.gov>
> Cc: Nu Xu <nxu AT lbl.gov>
> Subject: Re: [[Star-cf-l] ] WPCF 2024 talk
>  Dear Nu,
> Thank you so much for he feedback following is my response;
>     • Slide 11:  I incorporated your suggestions, and have only one nozero digit in all of the uncertainties, and rounded the parameter values accordingly.
>     • Slide 11: Thank you for pointing it out, it surely needs an explanation. I added the explanation of these parameters to slide 10 where they are discussed in last bullet point; let me also mention here that this essentially handles all residual, non-femtoscopic background, coming from energy and momentum conservation, resonance decays, bulk flow phenomena, minijets.
>     • Slide 14: I agree. I now include the chi^2 difference and the p-value (confidence level) for both fits. The reference has also been added for published data.
>     • Slide 15: Agree, it does need a bit explanation. Now I added 3 bullet points as an explanation.
> I have incorporated your suggestion in version 2. Please have a look.
> https://drupal.star.bnl.gov/STAR/node/69661
> Thank you.
> Best regards,
> Sneha
>
> From: star-cf-l-request AT lists.bnl.gov <star-cf-l-request AT lists.bnl.gov> on behalf of Nu Xu <nxu AT lbl.gov>
> Sent: Wednesday, October 30, 2024 12:17 AM
> To: STAR Correlations and Fluctuations PWG <star-cf-l AT lists.bnl.gov>
> Cc: Nu Xu <nxu AT lbl.gov>
> Subject: Re: [[Star-cf-l] ] WPCF 2024 talk
>  Hi Sneha,
>
> Thank you for the draft for WPCF2025. I have the following suggestions for your consideration:
> 1) slide 11 - middle plot: those numbers listed there are too precise, perhaps meaningless. For example, lambda could be 0.99+-0.05, R_out could be 6.7+-0.2 fm and so on;
> 2) slide 11: what are those epsilons? Why do we need them? Any physics meanings of these parameters?
>
> 3)  slide 14 - last three bullets: instead of these claims, can we simply list the fitting results of chi^2/pdf from both alpha=2 and free alpha fits? For the alpha =2 data, a reference should be provided.
>
> 4) slide 15: what is "Levy walk”? One should explain it in the talk, not just point to another talk in my view;
>
> That is all for now.
> Best regards,
>
> Nu
>
>
> > On Oct 29, 2024, at 5:26 AM, Bhosale Sneha <bhosales AT staff.elte.hu> wrote:
> >
> > Dear All,
> > I would like to let you know that the WPCF conference agenda has been released, and my talk is scheduled for the 5th of November 2024, a week from now. I would greatly appreciate if you could review my contribution before the 4th of November. Your feedback and suggestions would be invaluable in improving the presentation.
> >
> > https://drupal.star.bnl.gov/STAR/node/69661
> >
> > Thank you in advance for your time and support.
> >
> > Best regards,
> > SnehaFrom: star-cf-l-request AT lists.bnl.gov <star-cf-l-request AT lists.bnl.gov> on behalf of Bhosale Sneha <bhosales AT staff.elte.hu>
> > Sent: Wednesday, October 23, 2024 4:51 PM
> > To: STAR Correlations and Fluctuations PWG <star-cf-l AT lists.bnl.gov> <star-cf-l AT lists.bnl.gov>
> > Subject: [[Star-cf-l] ] WPCF 2024 talk
> >  Dear All,
> > Please have a look at my contribution for WPCF2024 talk and let me know your views.
> >
> > https://drupal.star.bnl.gov/STAR/node/69661
> >
> > Thank you very much for considering my request.
> >
> > Best regards,
> > Sneha