Skip to Content.
Sympa Menu

star-cf-l - Re: [Star-cf-l] CF PWG meeting Nov. 23rd 2023 time: 9:00 (BNL time)

Please Wait...

star-cf-l AT lists.bnl.gov

Subject: STAR Correlations and Fluctuations PWG

List archive

Chronological Thread  
  • From: Mate Csanad <csanad AT bnl.gov>
  • To: STAR Correlations and Fluctuations PWG <star-cf-l AT lists.bnl.gov>
  • Subject: Re: [Star-cf-l] CF PWG meeting Nov. 23rd 2023 time: 9:00 (BNL time)
  • Date: Thu, 23 Nov 2023 16:28:53 +0100

Dear Nu,

As some interpretatonal questions came up, let me send some details (many other things were discussed of course, and I'm reflecting just on two particular points). I hope it is okay to send this to the list, as opposed to sending it privately (i.e., I hope I assume right that this was the request during the presentation).

1) The interpretation of the Lévy alpha parameter
a) If the source shape changes for example with sqrt(sNN), then the dependence of the extracted Gaussian radii will entangle the size and the shape change. To disentangle this, one has to introduce the shape parameter as well. There is a backup slide about this in a CMS talk at WPCF, slide 22 of [1]. This also means that these parameters are not equivalent to Gaussian parameters, but the two present different experimental observables. Of course it is a question which is related to what actual physical object/parameter.
b) There are multiple physical reasons for the appearence of these power-law tails: jet fragmentation (more important in pp), critical phenomena (maybe important at low energies), anomalous diffusion or Levy flight during hadronic rescattering (might play a role at any energy), decays; see slide 21 of [1]. This really means that the value of alpha in AuAu outside of the "possibly critical" region may mostly be affected by anomalous diffusion, so it sort of measures the "degree of anomality". But the other physical reasons may play a role as well.

2) About the non-sphericality: indeed non-sphericality causes non-Gaussian 1D correlations, but this is completely different than what effect a Levy-type of source has, see slide 6 of [1]. The main point to stress here is that we are not just seeing non-Gaussianity, but the 1D results in particular point to Levy type of sources (i.e., correlation functions would look different if it would be an ellipsoidal Gaussian). But of course that's why the 3D analysis is important.

Best regards,
Mate

[1] https://agenda.infn.it/event/33324/contributions/209727/attachments/112865/161434/csanad_wpcf23_CMSLevyHBT.pdf

2023. 11. 23. 14:06 keltezéssel, Mate Csanad via Star-cf-l írta:
Dear Hanna and Nu,

Please find my material for today at
https://drupal.star.bnl.gov/STAR/system/files/csanad_3Dfits_CFPWG_2023nov23.pdf

Thanks, best regards,
Mate

2023. 11. 22. 12:18 keltezéssel, Mate Csanad via Star-cf-l írta:
Dear Hanna and Nu,

If possible, I would like to show just a very short (5 min) update on the 3D analysis that was discussed last week. It would not take much time, just reflecting on with new results on one or two things that came up last week. It would be great to have this after Daniel's talk, if possible.

Thanks, best regards,
Mate

2023. 11. 20. 12:24 keltezéssel, Hanna Paulina Zbroszczyk via Star-cf-l írta:
DearCFActivists,

We  invite you to our weeklyCFPWG meeting on *Thursday, November 23rd, 9:00 AM (BNL time)*.
If you would like to contribute, please let me know.

Please try to post your slides at your earliest convenient.
We will connect via Zoom. Please find the connection details under the meeting webpage.


Thank you,
Hanna and Nu

https://drupal.star.bnl.gov/STAR/blog/luoxf/correlations-and-fluctuations <https://drupal.star.bnl.gov/STAR/blog/luoxf/correlations-and-fluctuations>
https://drupal.star.bnl.gov/STAR/blog/gos/correlations-and-fluctuations-preliminary-plots

<https://drupal.star.bnl.gov/STAR/blog/gos/correlations-and-fluctuations-preliminary-plots>


*Hanna Paulina Zbroszczyk*
PhD DSc Eng, Professor WUT
*
*
*E-mail*: hanna.zbroszczyk AT pw.edu.pl
Tel: +48 22 234 5851 (office)

*Address*:
Warsaw University of Technology
Faculty of Physics
Nuclear Physics Division
Koszykowa 75
Office: 117b (via 115)
00-662 Warsaw, Poland



















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




Archive powered by MHonArc 2.6.24.

Top of Page