1. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba1 v n {EP} measurements with forward rapidity  n in 200GeV Au+Au collisions at RHIC-PHENIX ShinIchi Esumi for the PHENIX collaboration Inst. of Physics, Univ. of Tsukuba introduction higher order event plane correlations 2-particle correlations with rapidity gap v n {EP} results and comparisons summary

2. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba2 z y x Reaction Plane (x-z) y x y x arXiv:1003.0194 Higher order event anisotropy --- v 3 --- black-disk collision, sign-flipping v 3 like v 1 initial geometrical fluctuation, no-sign-flipping v 3

3. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba3 PRL104 (2010) 062301 Some couplings between “mach-cone-like and ridge-like emissions” and v 3 are expected to be there! What is the origin and what is the consequence? ridge shoulder

4. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba4 BBC MPC PbW0 4 2cm Pb converter in front RXN (zero degree n calorimeter ZDC/SMD /shower max detector) (reaction plane detector) (muon piston EM-calorimeter) (beam-beam quartz- Cherenkov detector) 05-5  dN/d  CNT (PHENIX central tracking arm)

5. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba5 Method of event plane determination (1) Detector calibration / cell-by-cell calibration (2) Q-vector, re-centering, normalization of width Q {n}x =  i { w i cos (n  i ) } Q’ {n}x = (Q {n}x - ) /  Q{n}x Q {n}y =  i { w i sin (n  i ) } Q’ {n}y = (Q {n}y - ) /  Q{n}y Q {1}x ZDC =  i { w i x i } /  i { w i } Q {1}y ZDC =  i { w i y i } /  i { w i } (3) n-th harmonics reaction plane  {n} = atan2 (Q’ {n}y, Q’ {n}x ) / n (4) Fourier flattening (Sergei’s+Art’s method paper) n  ’ {n} = n  {n} +  i (2/i) { - cos(i n  {n} ) + sin(i n  {n} ) } (5) measure v n w.r.t.  n and correct for E.P. resolution 2-particle correlation among 3-sub detectors Forward Hit (F), Backward Hit (B), Central Track (C) (1) measure d  distribution between 2 detectors weighting by the hit amplitude (2) normalize by the event mixing to make correlation functions for 3 combinations (3) fit the correlation with Fourier function to extract v n F v n B, v n F v n C and v n B v n C (4) v n F (Hit) and v n B (Hit) can be determined as a function of centrality (5) v n C (Track) can be determined as a function of centrality and p T

6. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba6 centrality (%) n=2 RXN n=3 RXN n=4 RXN n=2 MPC n=3 MPC  n = positive correlation in  3 between opposite  up to  3 ~ 4 no-sign flipping in  3, which is an indication initial geometrical fluctuation  n resolution estimated from Forward-Backward correlation  n{true} can be different for different order E.P. resolution of n-th order plane RXN |  | = 1.0 ~ 2.8 MPC |  | = 3.1~ 3.7 200GeV Au+Au PHENIX Preliminary

7. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba7 2 (  1 -  2 ) A: RXN(S)  [-2.8,-1.0] B: MPC(N)  [3.1,3.7] clear positive correlation in  1  2,  2  4 very weak negative correlation in  1  3 no significant correlation in  2  3 Correlation between different harmonics #1 (opposite arms) 3 (  1 -  3 )6 (  2 -  3 )4 (  2 -  4 ) centrality (%) (%) 200GeV Au+Au PHENIX Preliminary 4 0 0 0.1 0 050100

8. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba8 Correlation between different harmonics #2 (w.r.t spectator  1 ) centrality (%) A: BBC(S)  [-3.9,-3.1] B: BBC(N)  [3.1,3.9] (%) C: ZDC(S+N) |  5 1 (  1 -  1 ZDC(-) )2 (  2 -  1 ZDC(-) )3 (  3 -  1 ZDC(-) ) 200GeV Au+Au PHENIX Preliminary clear sign-flipping in v 1, clear positive v 2 indication of sign-flipping in v 3, sign(v 1 ) = sign(v 3 ) (N-side flipped to combine) 000 10 60.06

9. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba9 beam rapidity net-baryon spectator participant mid- rapidity beam rapidity spectator mid- rapidity fluctuating initial condition beam rapidity spectator mid- rapidity mach-cone like away ridge like near near side jet away side jet n-even : v n (  ) = v n (-  ) n-odd : v n (  ) = -v n (-  ) all n : v n (  ) = v n (-  ) case1case2case3

10. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba10 What we have observed with  n (1)clear correlation between  1 and  2 as well as  2 and  4, where v 2,4 have also been measured with lower order harmonic planes (2)participant (pion dominant) v 1 is opposite with respect to spectator v 1 as expected (already seen at RHIC and other energies) (3)weak correlation between  1 and  3 is seen as a signature of true v 3 with sign-flipping at mid-rapidity, same sign for both v 1 and v 3 (4)no significant correlation between  2 and  3 is seen within current statistical accuracy (5)clear correlations of same order  3,(4) are seen between detectors with wide rapidity gap, which is consistent with initial geometrical participant fluctuation commonly over wide rapidity space (6)The origin can also be jet-medium correlation, which can spread over wide rapidity space (coupled with earlier stage)

11. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba11 200GeV Au+Au 20~30% PHENIX Preliminary CNT: central tracks mid-rapidity (|  |<0.35) charged hadrons p T =2~4(GeV/c) RXN: reaction plane detector forward |  |=1.0~2.8 all cells/hits (charge weighting with Pb converter) MPC: muon piston calorimeter forward EM-cal |  |=3.1~3.7 all cells/towers (eT weighting) p n = v n A  v n B  (CNT)  (RXN)  (CNT)  (MPC) F(x) = A {1 + 2  k=1~2 [p k cos(kx)] } C 2 (  ) C 2 (  ) - F(  ) + 1 F(x) = A {1 + 2  k=1~4 [p k cos(kx)] } clear 3rd moment in two-particle correlation with large  gap CNT  RXNCNT  MPC 2-part. correlation between central and forward

12. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba12 central-central 2-part. correlation with  dependence 0<|  |<0.10.1<|  |<0.3 0.3<|  |<0.50.5<|  |<0.7 200GeV Au+Au 0-20%, inc.  -had.

13. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba13 p T (GeV/c) 200GeV Au+Au -> charged particles (|  |<0.35) 0~10%10~20%20~30%30~40%40~50%50~60% systematic errors are defined by the variations with  n from different  and from different methods including central-forward 2-particle correlation. Therefore it could include some physics biases. 0.0 0.1 0.2 0 2 4 v n {EP} 0 2 4 v 2 {  2 forw.  } v 4 {  4 forw.  } PHENIX Preliminary v 3 {  3 forw.  } no-sign-flipping v 3 v n {EP} at mid-rapidity with forward  n  n RXN (|  |=1.0~2.8) MPC (|  |=3.1~3.7) BBC (|  |=3.1~3.9)

14. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba14 black : 2-particle correlation (cent.-cent.) red : event plane method (  3 forward) agree at low p T, non-flow (i.e jet) effects at high p T comparison between v 3 {  3 forward} vs v 3 {2-part. cent.-cent.}

15. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba15 good agreement between data and theory! large  gap, bulk flow only small  gap, bulk + jet + ? Comparison with Hydro calculation v 3 {2-part. cent.-cent.} v 3 {  3 forward} Glauber initial condition  /s = 1/4  arxiv: 1007.5469

16. WWND 2011, Winter Park, CO, 7/Feb/2011ShinIchi Esumi, Univ. of Tsukuba16 Summary and outlook v n {EP} are measured at mid-rapidity with  n defined at forward  and with 2 particle correlation between forward-central. Long range clear positive correlation of  3 (non-sign-flipping v 3 ) is observed over several units of  There is an indication of sign-flipping v 3 in forward rapidity. v 3 {EP} at mid-rapidity measured with various forward detectors has similar p T dependence as v 2 {EP}, much smaller centrality dependence (but significant in central collisions). Further multi-particle correlation study including  n (with and without  gap) would answer the origin of this long range correlation; initial state geometrical fluctuation alone or jet-medium interaction at initial stage…