Charged hadron flow in Cu+Au
collisions at RHIC-PHENIX
Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	  Univ.	  of	  Tsukuba	  RIKEN	

08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

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Outline	üIntroductionüv2, v3 in CuAu collisionüv1 in CuAu collisionüSummary 	

19/5/2014	  QuarkMaMer	  2014	  	  Darmstadt,	  Germany	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

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Azimuthal Anisotropy	üThe Azimuthal Anisotropy is good probevn =< cos(n[φ − Φn ]) >n=1 Directed
n=2 Elliptic
n=3 TriangularInitial state geometryèη/s

19/5/2014	  QuarkMaMer	  2014	  	  Darmstadt,	  Germany	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

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v2,v3 in symmetric collision systems 	
PRL 107,252301 	

QM14 Poster, Reynollds 	

v2	v2	v3	v3	ü vn is studied in AuAu, CuCu collisions- Clear centrality dependence of v2 in AuAu, CuCu
- Weak / No significant centrality dependence ofv3 in AuAu, CuCu
08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

4	

Introduction of CuAu collisions	
Forward multiplicity vs Backward multiplicity	
Cu going 	

Glauber Monte Calro	600	Au going 	

900	

üAsymmetric collision provide us unique information- Left/Right difference in pressure gradient- Asymmetric η distribution
08/05/2014	  ATHIC14	  Osaka	Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

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Flow Measurement via EP method 	üvn is measured via EP method	

Au	Cu	

ü Charged Hadron track- CNT(|η|<0.35)- FVTX (1<|η|<3)	

dN/dη	üEP is estimated byMPC	
Forward/Backward detectorBBC	- BBC (3.1<|η|<3.9)
SMD	
- MPC (3.1<|η|<3.8)- SMD (|η|>6)
08/05/2014	  ATHIC14	  Osaka	

CNT	Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

FVTX	6	 η	Centrality dependence of v2, v3 in 200 GeV CuAu	v2	v3	

üCuAu v2, v3 (pt) are measured- Clear centrality dependence of v2- No Significant centrality dependence of v3
è Same centrality dependence as seen in symmetric collisions
08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

7	

Comparison to AuAu, CuCu v2	

üSystem size dependence- AuAu > CuAu > CuCu
- Originated from initial ε208/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

arXiv:1111.5095	

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Comparison to AuAu, CuCu v3	

üSmall system size dependence- It is expected from similar ε3- v3 is given by ε3
08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

arXiv:1111.5095	

9	

Comparison to Theory	Bozek,	  PLB	  717	  (2012)	  287	ü Comparison to Theory ( Glauber and 4πη =1(2) )- pT<1[GeV/c], Experimental data agree better with 4πη/s=1 ?
- pT>1[GeV/c], Experimental data agree better with 4πη/s=2 ?
08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

10	

0.04	

0

Ψ1	  Spectator	

v1	

0.02	

AuAu	 PRL	  97,	  012301	  (2006)	  	ParBcipant	-­‐0.02	-­‐0.04	

ParBcipant	Ψ1	  Spectator	

v1 in symmetric collision system 	v1	  <	  0	y	v1	  >	  0	φ − Ψ SPAu	η < 0	Au	 x	η > 0	ü Rapidity anti-symmetric(Traditional) : v1(η) = -v1(η)ü Definition of positive v1 : Ψ1 (η>0)- v1<0 -> more particles are emitted to Ψ1 (η<0)- v1>0 -> more particles are emitted to Ψ1 (η>0)
08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

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v1 Fluctuation in CuAu	

Ψ(n)PP	  :	  ParBcipant	  Plane	Ψ pSP	  :	  Spectator	  Plane(projecBle)	  Ψ tSP	  	  :	  Spectator	  Plane(target)	  ΨRP	  	  	  :	  ReacBon	  Plane	  Cu	Au	ü Spectatoris expected
to fluctuate
pt
pt
Ψ
≠Ψ
≠
Ψ
è SPPPSP èv1(Ψ SP) ≠v1(Ψ SP)èv1 = v1Traditional+ v1SP fluctuation
v1Traditional : v1(η) = -v1(-η)
v1SP Fluctuation : v1(η) = v1(-η)ü Are there two v1 components in CuAu ?
ü How asymmetric are two v1 components in CuAu ?
08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

12	η Symmetric/Anti-symmetric v1 in CuAu	
v1v1	  (Cu	  spectator)	  >	  0	0.040

Ψ1Cu	

charged particles, p integrated, s NN=200GeVT
BBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)

0.02

φ − Ψ Cu
SPAu	Cu	üv1=	  0	  at	  	  η=0	  in	  AuAu	  v1=0	  	  (η∼0)	  in	  AuAu	
Cu going
Au going

-0.02

-0.04

Ψ1Au	

 

40-50% Centrality-4 -3 -2-1

008/05/2014	  ATHIC14	  Osaka	

1234
η

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

13	η Symmetric/Anti-symmetric v1 in CuAu	
v1

v1	  (Cu	  spectator)	  >	  0	0.04

0Ψ1Cu	

charged particles, p integrated, s NN=200GeVT
BBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)

0.02

φ − Ψ Cu
SPAu	Cu	üv1=	  0	  at	  	  η=0	  in	  AuAu	  Au
ü v1	  	  w.r.t	  	  	   SP

Ψv1=0	  	  (η∼0)	  in	  AuAu	
Cu going
Au going-0.02-0.04

Ψ1Au	 40-50% Centrality-4 -3 -2-1

008/05/2014	  ATHIC14	  Osaka	

1234
η

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

14	η Symmetric/Anti-symmetric v1 in CuAu	
v1v1	  (Cu	  spectator)	  >	  0	0.04

0

Ψ1Cu	

charged particles, p integrated, s NN=200GeVT
BBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)

0.02

φ − Ψ Cu
SPAu	Cu	üv1=	  0	  at	  	  η=0	  in	  AuAu	  Au
ü v1	  	  w.r.t	  	  	   SPΨv1=0	  	  (η∼0)	  in	  AuAu	
Cu going
Au going

ü v1	  	  w.r.t	  	  ΨCuSP-0.02-0.04

Ψ1Au	 40-50% Centrality-4 -3 -2-1008/05/2014	  ATHIC14	  Osaka	

1234
η

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

15	

η Symmetric/Anti-symmetric v1 in CuAu	
v1

v1	  (Cu	  spectator)	  >	  0	0.04

0

Ψ1Cu	

charged particles, p integrated, s NN=200GeVT
BBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)

0.02

φ − Ψ Cu
SPAu	Cu	üv1=	  0	  at	  	  η=0	  in	  AuAu	  Au
ü v1	  	  w.r.t	  	  	   SPΨv1=0	  	  (η∼0)	  in	  AuAu	
Cu going
Au going

ü v1	  	  w.r.t	  	  ΨCuSPü v1(ﬂu)	  =	  (orange–blue)/2	  -0.02

ü v1(tra)	  =	  (orange+blue)/2	  -0.04

Ψ1Au	

 

40-50% Centrality-4 -3 -2-1

008/05/2014	  ATHIC14	  Osaka	

1234
η

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

16	η Symmetric/Anti-symmetric v1 in CuAu	
v1v1	  (Cu	  spectator)	  >	  0	0.04

0

Ψ1Cu	

Au	

charged particles, p integrated, s NN=200GeVTBBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)

0.02

φ − Ψ Cu
SPCu	üv1=	  0	  at	  	  η=0	  in	  AuAu	  Au
ü v1	  	  w.r.t	  	  	   SP

Ψv1=0	  	  (η∼0)	  in	  AuAu	
Cu going
Au going

ü v1	  	  w.r.t	  	  ΨCuSPü v1(ﬂu)	  =	  (orange–blue)/2	  -0.02

ü v1(tra)	  =	  (orange+blue)/2	  -0.04

Ψ1Au	

 

40-50% Centrality-4 -3 -2-10

123

ü v1(tra)	  	  is	  shiled	  to	  	  4 	  	  	  	  Cu	  going	  side	  	  η08/05/2014	  ATHIC14	  Osaka	Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

17	η Symmetric/Anti-symmetric v1 in CuAu	
v1

v1	  (Cu	  spectator)	  >	  0	0.04

Ψ1Cu	

Au	

charged particles, p integrated, s NN=200GeVTBBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)Cu	üv1=	  0	  at	  	  η=0	  in	  AuAu	  Au
ü v1	  	  w.r.t	  	  	   SPΨ

0.02

0

φ − Ψ Cu
SPCu going
Au going

ü v1(ﬂu)	  =	  (orange-­‐blue)/2	  v1>0	  ?	  (η∼0)	

-0.02

ü v1	  	  w.r.t	  	  ΨCuSPü v1(tra)	  =	  (orange+blue)/2	  -0.04

Ψ1Au	 40-50% Centrality-4 -3 -2-10

123

ü v1(tra)	  	  is	  shiled	  towards	  	  4 	  	  	  	  Cu	  going	  side	  	  η08/05/2014	  ATHIC14	  Osaka	ü v1(tra)	  >0?	  at	  η=0	  Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

18	

Summary	ü CuAu v2, v3(pt)- Clear centrality and system size dependence of v2- No significant centrality and system size dependence of v3
ü CuAu v1 (η)- negative slope in v1(Traditional) as a function of η- Rapidity η0(v1~0) is shifted towards Cu-going direction
or v1 > 0 at η ~ 0- negative v1(SP Fluctuation) : v1(Ψ1Cu)<v1(Ψ1Au)

08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

19	

Comparison to Theory	
Bozek,	  PLB	  717	  (2012)	  287	

08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

20	

v1 Even, Odd Components in PbPb 	
QM2011	  ALICE	  	  ü v1(even + odd) = v1(even) + v1(odd) is observed in PbPb 2.75[TeV]- v(even): v1(η) = v1(-η)- v1(odd) : v1(η) = -v1(-η)- The source of even component is expected from spectator fluctuationü Same EP(Spectator) dependence is seen.
- v1( EP η<0) > v1(EP η>0)08/05/2014	  ATHIC14	  Osaka	Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

21	

v1

v1

Centrality dependence of v1	
0.04

charged particles, p integrated, s NN=200GeVT
BBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)

0.020

Ψ1Cu	

charged particles, p integrated, s NN=200GeVT
BBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)

Ψ1Cu	0.02
Cu going
Au going

-0.02

-0.04

0.04

0Cu going
Au going-0.02

 

30-40% Centrality

Ψ1Au	 -4 -3 -2 -1 0

1234
η

-0.04

 

50-60% Centrality

Ψ1Au	 -4 -3 -2 -1 0

1ü The shift of v1 is seen between two spectator planes. (v1even)- v1{ΨS.P.(SMD Au-going η<0)} > v1{ΨS.P.(SMD Cu–going η>0)}- Same direction as seen in ALICE234ηü Both components show some centrality dependences- Odd : Clear shift of η0(v1~0) towards Cu-going direction (asymmetry in v1odd)- Even : No clear asymmetry (some possible difference between for./back.)
08/05/2014	  ATHIC14	  Osaka	Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

22	

v1
0.04

Ψ1Cu	

v1	  (|η|<0.35)	  x	  10	charged particles, p integrated, s NN=200GeVT
BBC AuAu
BBC CuAu (SMD-Au-going)
BBC CuAu (SMD-Cu-going)
FVTX CuAu (SMD-Au-going)
FVTX CuAu (SMD-Cu-going)v1<0	  (η∼0)	

0.02

0-0.02

-0.04

Ψ1Au	

v1	  (Au	  spectator)	  >	  0		v1	  (Cu	  spectator)	  >	  0	v1 x	  10v1 in CuAu	

Cu going
Au going

v1(pT) :More low pT particles are emitted to Cu side
More high pT particles are emitted to Au sidev1>0	  ?	  (η∼0)	

v1(even)	  =	  blue	  –	  orange	  v1(odd)	  	  =	  (blue	  +	  orange)/2	 

40-50% Centrality-4 -3 -2-10123

η0(v1~0), where v1 sign changes, is seen

to be shifted towards Cu-going direction
08/05/2014	  ATHIC14	  Osaka	Cu	

4
ηlow	  pT	Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

Au	high	  pT	23	v1 (pT) in CuAu 	

v1	  (Au	  spectator)	  >	  0	08/05/2014	  ATHIC14	  Osaka	

Hiroshi	  Nakagomi	  	  for	  the	  PHENIX	  collaboraBon	

φ − Ψ Cu
SPCu	Au	24