1. Masashi Kaneta for the PHENIX collaboration
Event anisotropy of identified p0, g and e compared to charged p, K, p, and d in sNN = 200 GeV Au+Au at PHENIX x z y
Masashi Kaneta
Masashi Kaneta
for the PHENIX collaboration
15 sec
Let me start event anisotropy talk from PHENIX about pi zero gamma and electron in 200 GeV Gold on Gold collisions.

2. 12 Countries; 58 Institutions; 480 Participants*
Brazil University of São Paulo, São Paulo
China Academia Sinica, Taipei, Taiwan
China Institute of Atomic Energy, Beijing
Peking University, Beijing
France LPC, University de Clermont-Ferrand, Clermont-Ferrand
Dapnia, CEA Saclay, Gif-sur-Yvette
IPN-Orsay, Universite Paris Sud, CNRS-IN2P3, Orsay
LLR, Ecòle Polytechnique, CNRS-IN2P3, Palaiseau
SUBATECH, Ecòle des Mines at Nantes, Nantes
Germany University of Münster, Münster
Hungary Central Research Institute for Physics (KFKI), Budapest
Debrecen University, Debrecen
Eötvös Loránd University (ELTE), Budapest
India Banaras Hindu University, Banaras
Bhabha Atomic Research Centre, Bombay
Israel Weizmann Institute, Rehovot
Japan Center for Nuclear Study, University of Tokyo, Tokyo
Hiroshima University, Higashi-Hiroshima
KEK, Institute for High Energy Physics, Tsukuba
Kyoto University, Kyoto
Nagasaki Institute of Applied Science, Nagasaki
RIKEN, Institute for Physical and Chemical Research, Wako
RIKEN-BNL Research Center, Upton, NY
Rikkyo University, Tokyo
Tokyo Institute of Technology, Tokyo
University of Tsukuba, Tsukuba
Waseda University, Tokyo
S. Korea Cyclotron Application Laboratory, KAERI, Seoul
Kangnung National University, Kangnung
Korea University, Seoul
Myong Ji University, Yongin City
System Electronics Laboratory, Seoul Nat. University, Seoul
Yonsei University, Seoul
Russia Institute of High Energy Physics, Protovino
Joint Institute for Nuclear Research, Dubna
Kurchatov Institute, Moscow
PNPI, St. Petersburg Nuclear Physics Institute, St. Petersburg
St. Petersburg State Technical University, St. Petersburg
Sweden Lund University, Lund
12 Countries; 58 Institutions; 480 Participants*
USA Abilene Christian University, Abilene, TX
Brookhaven National Laboratory, Upton, NY
University of California - Riverside, Riverside, CA
University of Colorado, Boulder, CO
Columbia University, Nevis Laboratories, Irvington, NY
Florida State University, Tallahassee, FL
Florida Technical University, Melbourne, FL
Georgia State University, Atlanta, GA
University of Illinois Urbana Champaign, Urbana-Champaign, IL
Iowa State University and Ames Laboratory, Ames, IA
Los Alamos National Laboratory, Los Alamos, NM
Lawrence Livermore National Laboratory, Livermore, Ca
University of New Mexico, Albuquerque, NM
New Mexico State University, Las Cruces, NM
Dept. of Chemistry, Stony Brook Univ., Stony Brook, NY
Dept. Phys. and Astronomy, Stony Brook Univ., Stony Brook, NY
Oak Ridge National Laboratory, Oak Ridge, TN
University of Tennessee, Knoxville, TN
Vanderbilt University, Nashville, TN
10 sec
This is the PHENIX collaboration from 12 countries, 58 institutions and 480 participants.
*as of January 2004
Masashi Kaneta, RBRC, BNL

3. Announcement * Students
The flow and event anisotropy from the PHENIX collaborators in the poster session
Shingo Sakai*
Azimuthal anisotropy of electrons/positrons in 200 GeV Au+Au collisions at RHIC-PHENIX
Andrey Kazantsev*
Elliptic flow of inclusive photons in Au+Au collisions at sNN=200 GeV from the PHENIX experiment at RHIC
Hiroshi Masui*
Measurement of directed flow in sNN=200 GeV Au+Au, d+Au, p+p collisions at RHIC-PHENIX
Akio Kiyomichi
Radial flow study from identified hadron spectra in Au+Au collisions at sNN=200 GeV (at PHENIX)
Michael Issah*
Azimuthal anisotropy measurements in PHENIX via cummulants of Multiparticle azimuthal correlations
Debsankar Mukhopadhyay
Elliptic flow of f mesons in Au+Au collisions at sNN=200 GeV (at PHENIX)
ShinIchi Esumi
Analysis of event anisotropy and azimuthal pair correlation
20 sec
Before start of my talk, I want to mention PHENIX poster related flow and event anisotropy.
The names colored by red are students.
It is not too late to go to poster session to read it.
Please go the poster session and talk with those students, especially.
* Students
Masashi Kaneta, RBRC, BNL

4. Motivations Event anisotropy p0 Photon Electron/positron
Sensitive to the initial state
Collectivity of hadron/parton  thermalization / recombination
Energy loss by Jet quenching  dense matter p0
Large pT coverage as an identified hadron
Large contribution of the decay to the following inclusive measurements
Photon
Radiation / Compton from hot gas
Photon flow?
Electron/positron
Open charm and bottom
Flow and energy loss of heavy flavors?
90 sec
We are interested in event anisotropy. It is one of reasons why you are here. OK?
The event anisotropy is sensitive to the initial state.
In the low pT region, we see collectivity of hadron and parton, and it relate to thermalization and recombination in the early stage.
And the energy loss by jet quenching is also important to find an evidence of dense matter, that is, QGP.
This talk focuses on pi0, photon, and electrons.
pi0 is good observable as identified hadron because technically the pT coverage in larger than the other hadrons.
And it makes large contribution of the decay to the photon and electrons yields.
We can have early stage of information by photon due to small cross section.
We don’t know whether photon flow exist, but if there is, it is interesting.
Our goal of electron analysis is for the open charm and bottom measurement.
It is interesting to see flow and energy loss of heavy flavors. p+
Masashi Kaneta, RBRC, BNL

5. The PHENIX experiment at RHIC
Photons/p0
Tracking : vertex be BBC to EMC hit positions
PID : EMCal
PHOENIX
Electrons
Tracking
DC, PC hits, vertex by BBC
PID
RICH (pT<4.9 GeV/c)
Energy/momentum cut by EMCal
Event centrality
BBC and ZDC
60 sec
The phenix experiment is at RHIC where stay in New York, Long Islands.
You can see the RHIC from the satellite.
The PHENIX is here at RHIC.
Photons pi0 are measured be Electro-Magnetic Calorimeters.
Electron is identified by RICH detector and EMC.
The event centrality is defined by Beam-Beam counters and Zero-Degree Calorimeter stay here
The selection of centrality is like this in PHENIX.
Masashi Kaneta, RBRC, BNL

6. Method of v2 Measurement
reaction plane angle
event anisotropy parameter measured
azimuthal angle of the particle
vnreal = vnmeasured/ (reaction plane resolution)n
Note: the detail of reaction plane definition will be found in nucl-ex/
Define reaction plane by charged multiplicity on Beam-Beam Counters
Photons
Obtained the second harmonic coefficient v2 from <cos[2(f-r)]> p0
p0 reconstruction and background subtract (combinatorial and the others)
For each pT, azimuthal angle, centrality
Combine both information
Counting number of p0 as a function of f-r and fit by the formula
Electrons
Both methods are used
The analysis of pi zero v2 is done as the following steps.
The Reaction plane is defined by charged multiplicity on Beam-Beam counters.
The pi zero is reconstructed by two photon measured by EMC.
Both information are combined and we obtained pi zero distribution as a function of the following formula.
Here, the cross section is describe pT, rapidity and Fourier expansion of phi minus reaction plane.
The vn is event anisotropy parameter measured and it is smeared by uncertainty of reaction plane.
It is corrected by reaction plane resolution.
Masashi Kaneta, RBRC, BNL

7. Reaction plane definition
North
South cm
⊿η = 3.1 ~ 4.0
⊿φ = 2π
inner ring
middle ring
outer ring
North
South cm
⊿η = 3.1 ~ 4.0
⊿φ = 2π
64 elements
Quartz Cherenkov radiator
meshed
dynode
PMT
inner ring
middle ring
outer ring
BBC
- p / p/2
Correlation of reaction planes
Masashi Kaneta, RBRC, BNL

8. g & p0 v2
3 sec
let me start from gamma and pi0 v2 results.

9. Inclusive photon v2 and p0 v2 in 200 GeV Au+Au
Note :
Inclusive photon = including all of the decay effect from hadrons
vertical bar : stat. error
curves, gray box : sys. error
, 200 GeV Au+Au
, 200 GeV Au+Au
, 200 GeV Au+Au
phenix preliminary
phenix preliminary
phenix preliminary
90 sec
Here is inclusive photon v2 and pi0 v2 as a function of pT for there centrality bins, top 20, 20-40, %.
You can see the both v2 are increasing with pT until around 3 GeV of pT, then saturated.
The photon we measured is including hadron decays mainly pi0.
For the our goal, we need to subtract the decay effect to see thermal and direct photon
However, to see them, we need more statistics.
pT [GeV/c]
Inclusive photon v2 shows similar tendency with p0
Need more statistics to see photon v2 after p0 (and also h) decay effect subtraction
Masashi Kaneta, RBRC, BNL

10. p0 decay effect for photon v2 (MC)
Test 1
Test 2 v2
0.35
0.3
0.25
0.2
0.15
0.1
0.05
-0.05
p0 v2 for MC input
p0 v2 generated
g v2 from p0 decay
60 sec
I said, we need more statistics.
However, it is no reason to wait for starting the decay effect study until we have fine data.
This is a result of the study.
Assuming pi0 v2 as shown by solid line, we can generate pi0 and process decay effect in Monte-Carlo.
The tool is ready, then once we have better statistics we can subtract the decay effect from inclusive photon.
pT [GeV/c]
Tool is ready for the decay effect in photons
Masashi Kaneta, RBRC, BNL

11. <v2> vs. centrality from 200 GeV Au+Au
Npart
Npart
200 GeV Au+Au
200 GeV Au+Au
phenix preliminary
phenix preliminary
Vertical bar : stat. error
Gray Box : sys. error
Masashi Kaneta, RBRC, BNL

12. v2 vs. pT vs. centrality from 200 GeV Au+Au
Statistical error is shown by error bar
Systematic error from p0 count method and reaction plane determination is shown by horizontal bar
The data point stays at <pT> in the bin and horizontal bar shows the bin range
The charged p and K v2 are shown only with statistical errors
200 GeV Au+Au
phenix preliminary
} nucl-ex/
Charged meson v2 consistent with p0 v2 in pT<4 GeV/c
Masashi Kaneta, RBRC, BNL

13. v2 vs. pT (Min. Bias) from 200 GeV Au+Au
Identified particle v2 up to pT=10 GeV/c
Consistent with charged pions
200 GeV Au+Au Min. Bias
phenix preliminary
}nucl-ex/
Also
Similar pT dependence with charged hadron v2
Low pT : consistent with hydrodynamical calculation
High pT : interesting to compare to a jet quenching calculation/ fragmentation-recombination model
Vertical bar : stat. error
curves, Gray Box : sys. error
The data point :at <pT> in the bin
36.3106 [events] = 5.3± [(mb)-1]
0.5
0.4
Masashi Kaneta, RBRC, BNL

14. v2 : Identified hadrons at mid-rapidity
PHENIX p, K, p
in nucl-ex/
and they are consistent with STAR data
PHENIX p0, d+d
preliminary data
STAR K0S , L+L
in nucl-ex/
200 GeV Au+Au Min. Bias
Difference between meson and baryon
Hydrodynamical picture can
describe mass dependence of v2
Masashi Kaneta, RBRC, BNL

15. Coalescence picture It is established for the nuclei cross section
200 GeV Au+Au Min. Bias
preliminary
} nucl-ex/
A : nuclear number
P : momentum
p = P/A
BA : coalescence parameter
Masashi Kaneta, RBRC, BNL

16. Quark coalescence? qqmeson, qqq(qqq)Baryon What data looks like? - -
Phys. Rev. Lett. 91 (2003) , D. Molnar and S.A. Voloshin
qqmeson, qqq(qqq)Baryon
What data looks like? - - - -
200 GeV Au+Au Min. Bias
Non-strange and strange mesons and baryons seem to be merged around pT/nquark 1-3 GeV/c
With more statistics, we may discuss precisely
Masashi Kaneta, RBRC, BNL

17. e± v2

18. Non-photonic e± v2 Have a look of the poster for detail discussion
Shingo Sakai
Azimuthal Anisotropy of electrons/positrons in 200 GeV Au+Au Collisions at RHIC-PHENIX
Takashi Hachiya
Single Electrons From Semi-leptonic Decays of Heavy Flavor in Au+Au Collisions at sNN=200 GeV
Non-photonic electron (sorry for jargon) means
Measured electron minus background:
hadron decay
g conversion
that is, charmed
(+bottomed) electron
we think
0.3
0.25
0.2
0.15
0.1
0.05
-0.05
-0.1
non-photonic electron v2
pT [GeV/c]
The data point : on <pT> in the bin
horizontal bar : RMS of dN/dpT
Two scenarios in nucl-th/
thermalized charm + transverse flow
no re-interaction
Data is consistent with both scenarios
Masashi Kaneta, RBRC, BNL

19. Summary

20. Summary First measurement of p0, g, e v2 at RHIC p0 v2 g v2 e v2
Minimum bias data (pT =1-10 GeV/c)
v2 at the highest pT from the identified particle analysis
Non-zero p0 v2 up to pT ~8 GeV/c
Charged p v2 consistent with p0 v2 in pT =1-3 GeV/c
Quark coalescence picture seems to work
from combining various hadron v2’s at RHIC
g v2
Centrality (top 20, 20-40, 40-60%) and pT dependence (in pT <5 GeV/c) are consistent with p0
With more statistics from run4, we hope to reject the decay effect
e v2
Minimum bias data (pT = GeV/c)
Non-photonic e v2 is consistent with both models:
charm flow and no-charm flow
We can discuss more precisely with more data.
Masashi Kaneta, RBRC, BNL

21. New results of charged hadron vn
Have a look of the poster for detail discussion
Hiroshi Masui
Measurement of directed flow in sNN=200 GeV Au+Au, d+Au, p+p collisions at RHIC-PHENIX
Elliptic
Flow
Directed
Flow
Masashi Kaneta, RBRC, BNL