STAR Correlations and Fluctuations PWG

[Grigory Nigmatkulov <nigmatkulov AT gmail.com>]

Hi Helen,

MEPhI group is working on that for kaons. We will try to show the update at the collaboration meeting.

Working with other species is challenging due to statistics.

Cheers,

Grigory

On Fri, 20 Aug 2021 at 17:46, Helen Caines via Star-cf-l <star-cf-l AT lists.bnl.gov> wrote:

Hi All,

  At this week’s LBNL BES workshop there was a brief discussion triggered by the difference in shapes of our reported HBT R_out^2 - R_side^2 vs sqrt(s) which might be related to an extended emission duration due passing through a first order phase transition, and the excess dilepton yield per pion which is also theoretically related to the lifetime of the source.

The HBT result shows a wide peak around 20 GeV while the dilepton results appear flat. See for example slides 18 and 20 of my presentation here: https://drupal.star.bnl.gov/STAR/files/STARPlansBES-II_0.pdf

I know that the two measurements measure different timescales so the absolute values don’t need to agree, but I thought both should be sensitive to potential extended freeze-outs generated via a first order phase transition. I was therefore wondering of this group if we see this HBT peaking in other species? Or rather, since the BES-II data are only just coming in, will we have the statistic to look at this and is someone currently planning to make the measurements?

Also, at the start of RHIC/STAR there were measurements of “total time of collision” being extracted from HBT+ spectra blast wave fits. I haven’t seen anyone attempting this in quite some time. Is it still considered a valid analysis technique? If so and we perform the study do we see a similar peaking? 

Thanks

Helen

***********************

Yale University
Physics Dept. - Wright Lab.
PO Box 208120
New Haven, CT 06520
203-432-5831
***********************
she/her/hers
"Life is not about waiting for the storms to pass.
It's about learning how to dance in the rain." - Vivian Greene

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