Shengli Huang Vanderbilt University for the PHENIX Collaboration Measurements of , K and proton v2 and v4 in 200GeV Au+Au collisions by the PHENIX experiment Shengli Huang Vanderbilt University for the PHENIX Collaboration

Observables and Motivation Analysis methods Results and Discussion Outline: Observables and Motivation Analysis methods Results and Discussion Conclusions 2019/4/27 S.L. Huang SQM08

Anisotropic flow v2 and v4 x y beam reaction plane Peter Kolb, PRC 68, 031902 Spatial space asymmetry momentum space asymmetry Azimuthal correlation with the reaction plane Built up in the early stage and self-quenched, therefore supply the early information of matter generated in the collision 2019/4/272019/4/27 S.L. Huang SQM08

NCQ Scaling PHENIX, PRL. 99, 052301 (2007) Baryon and meson elliptic flow follow the number of constituent quark(NCQ) scaling as a function of KET at low KET. NCQ scaling will break at intermediate pT if we assume that  is mainly from the recombination of TS partons but proton is mainly from TTS and TSS . NCQ scaling indicates the coalescence of the thermal parton How about the higher order anisotropic flow such as v4? Can we test this scaling break at high pT? Hwa &&Yang arXiv:0801.2183[nucl-th] SL Huang SQM08 2019/4/27

L <q> C E a  D Color Charge dependence 2 L <q> C E s a  D ^ 1.Gluon will lose more energy by gluon radiation in medium 2.The contribution from gluon jet fragmentation is different for pion, kaon(KS) and proton. The measurements of pion, kaon and proton and their anti-particles’ v2 will help us to study the color charge effect on energy loss S. Wicks et al,Nucl.Phys.A784:426-442,2007 S. Albino, B.A. Kniehl, G. Kramer, NPB 725 (2005) 181 4/27/2019 SL Huang SQM08

V4/(v2)2 ratio v4 /v22 is a probe of ideal Star Preliminary v4 /v22 is a probe of ideal hydro behavior and related to the degree of thermalization! Peter Kolb, PRC 68, 031902(2003); R.S.Bhalerao et.al PLB 627,49(2005); Borghini and Ollitrault,PLB642,227 (2006) The identified particles v4/v22 ratio should provide more detailed information than that of charged hadron Y.T. Bai QM06 S.L. Huang SQM08 2019/4/27

TOFw and Aerogel Detectors M2 unit need change TOFw intrinsic timing resolution is ~ 75ps /K can be separated to 2.8 GeV/c and K/p can be separated to 4.5 GeV/c 3. Together with Aerogel detector(ACC), we can identify the K to pT~4 GeV/c and , p to 7 GeV/c 2019/4/27 SL Huang SQM08

Reaction plane Measurements RxNP: Two sets of plastic scintillators positioned on either side of the collision vertex 12 segments in  2 segments in  1.0 < || < 1.5 1.5 < || < 2.8 BBC: 3.1<||<3.9 Both detectors are away from mid-rapidity. Smaller non-flow effect on the reaction plane measurements New RxNP detector resolution is around 74% at mid-centrality Sqrt(2*cos(2*(N-S))) 2019/4/27 SL Huang SQM08

Identified particles elliptic flow The proton’s v2 approaches to pion’s v2 as pT increases. It indicates the baryron production smoothly transits from TTT->TTS->TSS->SSS The kaon’s v2 is similar to the pion’s v2 as a function of KET. If particles production is dominated by jet fragmentation as pT~6GeV/c, the data indicates that the gluon will lose similar energy as light quark SL Huang QM08 2019/4/27

NCQ Scaling The NCQ scaling is broken as KET/nq>1GeV. It is consistent with theory calculation by assuming that the pion is from TS recombination but the proton is from TTS or TSS recombination at intermediate pT SL Huang QM08 2019/4/27

KET Scaling of v4 A.Taranenko The v4 follows the KET scaling well for KET < 1 GeV The number of constituent quark scaling holds for v4 when KET/nq < 1GeV. This confirms that matter with partonic degrees of freedom has been generated at RHIC 2019/4/27 S.L. Huang SQM08

V4/(v2)2 ratio The ratio of v4/(v2)2 is close to 0.9 for the , K and p Mesons and baryons have similar v4/(v2)2 ratio 2019/4/272019/4/27 S.L. Huang SQM08

How to Coalesce? Simple co-mover model at low pT baryon(TTS) Recombination at Intermediate pT Meson Baryon Meson Baryon thermal L.W. Chen, C.M. Ko nucl-th 0602025 shower Not only at intermediate pT region, even at low pT region, the particle is coalesced by the partons with different momentum SL Huang QM08 2019/4/27

Conclusions 1. The number of constituent quark scaling has been observed for v4 for KET/nq < 1 GeV. Mesons and baryons have similar v4/(v2)2 ratio which is close to 0.9 2. The proton’s v2 approaches to the pion’s v2 at pT~6GeV/c. And the kaon’s v2 is similar with pion’s v2 as a function of KET. 3. The NCQ scaling is broken at KET/nq~1GeV 2019/4/27 SL Huang SQM08