ReCentering method:

• In the ReCentering method one subtracts from Q-Vector the Q-Vector per particle
  averaged over many events (see also:
  www.star.bnl.gov/protected/bulkcorr/posk/reCentering/ReCentering.ppt.pdf):

  Q_nxi -= 〈cos(nφ)〉, Q_nyi -= 〈sin(nφ)〉 

  TVector2 reCent = (〈cos(nφ)〉, Q_nyi -= 〈sin(nφ)〉) per particle

  Q_x += (cos(nφ) - reCent.X())
  Q_y += (sin(nφ) - reCent.Y())

• The correction table is binned in curvature, η and run number:
  • 4 bins in η from -1.0 - 1.0
  • 2 bins for curvature from 0.0 - 0.25
  • 2 bins for charge
    
    
• and divided into four sectors:
  • Far West: η > 0 and ZVertex > 0
  • West:       &#951; > 0 and ZVertex < 0
  • Far East:  &#951; < 0 and ZVertex > 0
  • East:        &#951; > 0 and ZVertex < 0        
              
• Creation of two equally sized sub events and particles 
  lists are randomized 
• No p_t-weights are used 
         
• 0-5% most central:

 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 

 

 

 

 

 

• 5-10% most central:

 

 

 

 

 

 

 

 

 

 
 
 
 
 
 
 
 
 
 
 

 

 

 

 

• 10-20% most central: 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  

• 20-30% most central:

 

 

 

 

 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 

 

 

•  30-40% most central:

 

 

 

 

 

 

 

 
 
 
 
 
 
 
 
 
 
 
 
 

 

 

 

 

 

• 40-50% most central

 

 

 

 

 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 

 

 

•  50-60% most central:

 

 

 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 

 

 

• 60-70% most central 

 
 
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

•  70-80% most central

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Event Plane Resolution: 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

• Thanks to Art and Alex for the discussion

 
v₂ results:

• v₂ vs pt and &#951;

 

 

 

 

 

 

 

 

 

 

 

 

 

• v2 for identified particles vs pt and &#951; for 0-80% most central collisions. 
• PID identification will be improved
• Working on charged separated PID look for effects of the softest point especially for Pions and
  Protons (see: Horst St&#246;cker: Nucl. Phys. A 750 (2005) 121 and Peter Kolb et al.: 
  Phys. Rev. C 62 (2000) 054909)

 

 

 

 

 

 

 

 

 

 

 

• NCQ scaling seems to hold (still deconfinement) 
  (see: B. I. Abelev et al.: Phys. Rev. C 75 (2007) 54906
  B. I. Abelev et al.: Phys. Rev. C 99 (2007) 1112301
  B. I. Abelev et al.: Phys. Rev. C 77 (2008) 054901
  B. I. Abelev et al.: Phys. Rev. C 81 (2010) 044902)

 

 
 
 
 
 
 
 
 
 
 
 
 

 

 

 

 

 

• Comparison to other measurements at 39 GeV (Thanks to Alex and Shusu
  for the numbers)
• Alex and Shusu used phi-Weights but Alex included
  also p_t-weights into his analysis to enhance the resolution
• Issues with the 0-10% most central bin (similar 0-80% most central
  since 0-10% is also included into it). Good agreement for 10-40% 
  and 40-80% most central (still under investigation)

   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  

• NCQ scaling comparison to other measurements

  

 

 

 

 

 

 

 

 

 

 

 

 

 

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