STAR Flow, Chirality and Vorticity PWG

[Shengli Huang <shengli.huang AT stonybrook.edu>]

Dear All,

    As we discussed the nonflow estimation in PWG, there are many numbers being referenced. To facilitate our discussion, I believe it would be helpful to compile the nonflow estimates from different groups.

Fuqiang has uploaded a paper to arXiv: arXiv:2407.12731. You may focus on pages 11 and 12 if you're interested.

According to the paper, the nonflow estimate for 0–5% Au+Au collisions, derived from pp data using the scalar product method, is 12%. This value is nearly identical to what I presented in PWG: Presentation link.

For the 30% nonflow estimate from 70–80% Au+Au collisions, the paper mentions that this value is likely overestimated. Additionally, the 1-D fit method gives a nonflow estimate of 20%.

I am also aware of a paper on CME after nonflow subtraction in STAR. Does that paper use the 1-D fit methods? How would the conclusions change if we instead used the nonflow estimate from the scalar product method? Since Fuqiang frequently emphasizes internal consistency, I wonder if the conclusions remain robust when different methods are applied.

 

Thanks!

Shengli