STAR Flow, Chirality and Vorticity PWG

[Jiangyong Jia <jiangyong.jia AT stonybrook.edu>]

Hi, Sergei,

From your plot, you should focus on low pT region at 0.5 GeV (the first data point) with is the mean pT for particles we are using, it is not 30%.

But again, non-flow is a physical correlation that is only well defined in low multiplicity event. The correlation shape in eta and phi at low pT is nothing like jet fragmentation in AA collisions due to jet quenching.

The 70-80% centrality signal is not all non-flow as shown in the small system flow paper.

Cheers,

Jiangyong

On 1/25/24 7:44 PM, Sergei Voloshin via Star-fcv-l wrote:

Hi all,

        I would
          agree with Fuqiang's estimate. (In terms of v^2) the nonlfow
          in central collision is likely around 30%. Look at the right
          plot in 
        
        
        
        
          
        With
          eta-subevents the nonflow contribution can be probably
          reduced, but I doubt it can be suppressed by a large factor. 
        
        
        
        A couple
          other comments
        
        - I
          disagree that "quenching and thermalization" would reduce
          non-flow. As I mentioned I would probably expect a slight
          increase, but again this has to be studied. Without any real
          confirmation of either effect, we should probably preat it as
          unmodified.  
        
        
        
        - Most
          real flow in the most peripheral ( and for sure any _real_
          flow in pp) would play a role of nonflow in AA, as the "event
          planes" individual NN collisions are uncorrelated with the
          participant plane in AA.
        
        
        regards,
        Sergei