Christina MarkertMCM Toledo, Oct 2005

1
Elliptic flow and polarization of the f
Christina Markert, Kent State University
Introduction f Reconstruction
Results Conclusion
Thanks to Sergei and Ilya, Wayne State University
2
V2 for resonances

• Do resonances show mass
• splitting at low pt?
• Will a mass shift of resonances
• show up in the low momentum
• region ?
• Do resonances show quark
• scaling for elliptic flow ?
• Will rescattering and
• regeneration of resonances
• affect v2?
• How is the background flowing ?

3
Resonance signal loss in low momentum region
W. Florkowski, SQM2004
UrQMD Marcus Bleicher and Jörg Aichelin Phys.
Lett. B530 (2002) 81. M. Bleicher and Horst
Stöcker .Phys.G30 (2004) 111.
Does signal loss or late regeneration In low pT
region change v2?
4
Elliptic Flow v2 of Resonances
C. Nonaka, et al., Phys.Rev.C69031902,2004
Higher v2 at pt4 due to final state
Interactions. Quark scaling 5 and 4 for S(1385)
and K(892)
5
f reconstruction in AuAu (20-40)
20-40 centrality Track cuts Kaon p0.2,0.8
GeV dedx-2,2
Inv mass (KK-) GeV
Signal/Bg 2.9 Sig/sqrt(Bg) 100
Inv mass (KK-) GeV
6
Reaction plane resolution
Resolution 60
?
cos (2?1- 2?2)
7
f elliptic flow v2 in minbias AuAu (Y4)
f pT 1.0-1.5 GeV
v2obs7.11.1
resolution 60
dN/d(f-?)
f signal
2(f-?)
v2obs9.80.02
dN/d(f-?)
Bg of f invmass
2( f-?)
v2obs8.10.005
Higher v2 for background Due to quark scaling of
4 (K K-) ?
dN/d(f-?)
All Bg
2(f-?)
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f v2 STAR and PHENIX
f STAR
STAR
f PHENIX
Dipali Pal QM2005
Xiangzhou Cai QM2005
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f polarization in AuAu (20-40)
pT 1.0-1.5 GeV
? azimuthal angle of Kaon in f rest frame
Pq-1.11.1
dN/d(?-?)
Z.T.Liang and X.N. Wang nucl-th/0411101
f signal
2(?-?)
Polarization r00 1 Pq2/ 3- Pq2
Pq-2.10.02
dN/d(?-?)
Prediction for Pq 0.3
Bg of f invmass
2(?-?)
Pq-3.00.005
Background shows larger Polarization ?
dN/d(?-?)
All Bg
2(?-?)
10
f polarization in AuAu (20-40)
pT 1.0-1.5 GeV
phi azimuthal angle of Kaon in f rest frame
Pq-1.11.1
dN/d(phi-RP)
Polarization r00 1 Pq2/ 3 Pq2
f signal
Z.T.Liang and X.N. Wang nucl-th/0411101
2(phi -RP)
Pq-2.10.02
dN/d(phi-RP)
Pq prediction -0.3
Bg of f invmass
2(phi-RP)
Pq-3.00.005
dN/d(phi-RP)
All Bg
2(phi-RP)
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Conclusion

• v2 for f follows Kaon v2.
• v2 of (KK-) background pairs are larger than v2
  f.
• What is v2 doing for rescattering and
• regeneration of resonances ?
• - does quark scaling change to 4 and 5 for
  regeneration of
• resonances ?
• - v2 should be measured for D, L, S.
• Polarization of f is smaller than expected
• ( K and other resonances ?)
• Questions for theory
• Can v2 show the mass shift of resonances in
  low pT region ?
• Will different production mechanism of
  resonances change v2 ?