2009/06/181

重离子碰撞和核物质相变

马余刚中国科学院上海应用物理所

(SINAP, CAS)

• Brief introduction of SINAP • Introduction: phase diagram of nuclei• Liquid gas phase transition around 100 MeV/u• RHIC Physics & sQGP for Au+Au @ 200GeV/c• China STAR-TOF Team’s Contribution• Summary and Outlook

2009/06/18 Y. G. Ma, talk @ SDU

Two campus of SINAP in Shanghai

Jiading-SINAP

2009/06/18 Y. G. Ma, talk @ SDU

Bird View of SINAP in Jiading

2009/06/18 Y. G. Ma, talk @ SDU

Bird View of SINAP in Zhangjiang

2009/06/18 Y. G. Ma, talk @ SDU

上海光源建筑构思：艺术与科学的结合

2009/06/18 Y. G. Ma, talk @ SDU

上海光源首批线站；目前正开展各类实验

序号 线站名称 光源 束线主要性能指标

1生物大分子晶体学

小间隙波荡器

能量范围： 518keV聚焦光斑尺寸： 0.1~0.2mm光通量： 1011~1012phs/s能量分辨： 10-4 ，光束发散角： < 0.2mrad

2 X 射线衍射 弯铁能量范围： 430 keV聚焦光斑尺寸： 0.2mm, 光通量： 1011phs/s 能量分辨： 10-4 ；角度分辨： 10-4

3 XAFS扭摆器

能量范围： 425 keV聚焦光斑尺寸： ~0.4mm, 光通量： 1011phs/s 能量分辨： 510-510-4

4硬 X 射线微聚焦及应用

小间隙波荡器

能量范围： 520keV聚焦光斑尺寸： 0.25m; 光通量： 10101012phs/s; 能量分辨： 10-4

5X 射线成像及医学应用

扭摆器

能量范围： 872.5 keV单色光光通量： 1012~1013phs/s单色光 / 白光，不聚焦光束

6软 X 射线扫描显微

波荡器

能量范围： 2502000eV聚焦光斑： 50150nm谱分辨率 (E/E): >1000输出光子通量： >108(photons/s)

7 X 射线小角散射 弯铁能量范围： 430 keV聚焦光斑尺寸： 0.2mm, 光通量： 1011phs/s 能量分辨： 10-4 ；角度分辨： 10-4

2009/06/18 Y. G. Ma, talk @ SDU

加速器学科主要研究内容• 第三代同步辐射光源相关的加速器科学与技术。• 自由电子激光相关的加速器科学与技术• 新型光源相关的加速器物理科学与技术• 应用加速器（烟气脱硫用，治疗与制药用质子〈重离子〉加速器 ；

等）科学及相关技术。• 光子科学主要研究内容

（同步辐射、自由电子激光、 T-ray)

先进光源物理• 先进束线光学与技术• 新光源实验方法学• 部分应用研究• 上海光源建设新线站（约 50条）

上海应用物理研究所主要学科方向上海应用物理研究所主要学科方向

2009/06/18 Y. G. Ma, talk @ SDU

核物理与核技术主要研究内容• 核物理研究• 辐射化学与辐照技术• 放射性药物（ + 医学物理）• 先进探测仪器（毒品、爆炸物检测技术，生物识别技术，

分子成像技术）• 核能相关基础性研究

交叉学科主要研究内容• 核分析科学与技术（基于粒子束的纳米材料、分子环境科

学、 T-ray 物理与生化效应研究）• 物理生物学（单分子操纵、生物传感器、细胞与毒理）• 水的科学与技术（纳米尺度水的性质研究、废水处理科学

与技术）

2009/06/18 Y. G. Ma, talk @ SDU

核物理研究方向1 、同位旋依赖状态方程和中能放射性核束物理 实验设施：国家重离子加速器，日本理化所，美国 Texas A&M 大学等

2 、相对论重离子碰撞和 RHIC-STAR 合作 实验设施：美国 BNL-STAR 国际合作

3 、上海激光电子伽马源研制及其应用 实验设施：上海光源

4 、同质异能态核素受激发射研究 实验基地：浦东科技园区

5 、无中微子的双 β 衰变研究和 CUORE 合作 实验基地：意大利 Gran Sasso 地下实验室

6 、核能数据库研究

2009/06/18 Y. G. Ma, talk @ SDU

核物理课题组主要研究方向、经费支撑、获奖、研究生培养主要研究方向：• 相对论重离子碰撞物理• 远离 β 稳定线核素的结构和反应• 低中能重离子反应中的液气相变• 激光电子－光源的可行性研究• 暗物质研究重要国际合作： RHIC-STAR 国际合作（美国） CUORE 中微子国际合作（意大利）研究队伍： 中科院院士 1 人，博导 4 人，副研 8 人，助研 2 人，学生近 30 人获奖情况：• “ 重离子核反应的集体效应和奇异核的性质”，获 2001 年度国家自然科学奖二等奖• “ 中能重离子碰撞中的核液气相变和同位旋相关的物理研究”项目，获得 2008 年度上海市自然科学二等奖经费支撑： • 中科院重要方向性项目• 973 课题 - 放射性核束物理与核天体物理• 重大国际合作项目 “ RHIC-STAR TOF 物理” • 上海市重点基金、青年科技启明星计划• 近 10 项国家自然科学基金面上、青年项目研究生培养： 每年招收核物理方向研究室 8 人左右； 在培养的博士生中，有 2 人获得中科院院长特别奖学金，有 6 人获得了中科院院长奖学金优秀奖。

2009/06/18 Y. G. Ma, talk @ SDU

6th China-Japan Joint Nuclear Physics Symposium

May 16-20, 2006, ShanghaiAIP Conference Proceeding No. 815 will be available soon!

2009/06/18 Y. G. Ma, talk @ SDU

“19th Int. Conf. on Ultra-relativistic Nucleus-Nucleus Collisions”

(Quark Matter 2006)

Nov. 14-20, 2006

In Shanghai Science Hall

http://www.sinap.ac.cn/qm2006

~600 participants

2009/06/18 Y. G. Ma, talk @ SDU

Building Blocks of Hadron World

Proton Neutron

(uud) (udd)

Mesons

(q-q)

Exotics

(qqqq-q,…)

Molecules

Atoms

Electrons

Strong interaction is due to color charges and mediated by gluons. Gluons carry color charges too.

Baryon Density: = baryon number/volumenormal nucleus 0 ~ 0.15 /fm3 ~ 0.25x1015 g/cm3

Temperature, MeV ~ 1.16 x 1010 K10-6 second after the Big Bang T~200 MeV

Nucleus

Hyperons

(s…)

2009/06/18 Y. G. Ma, talk @ SDU

Introduction QCD and QGPIntroduction QCD and QGP

-

matter

atom

nucleusstrong interactiongluons and quarksconfined inside hadrons

2009/06/18 Y. G. Ma, talk @ SDU

Phase transition in hadronic world

By Morretto

2009/06/18 Y. G. Ma, talk @ SDU

Confinement potential

2009/06/18 Y. G. Ma, talk @ SDU

产生和研究解禁闭的夸克－胶子系统

核物质（禁闭！）

强子物质（禁闭！）

夸克胶子等离子体解禁闭 !

方法• 加热• 压缩 “ 夸克－胶子等离子体”

Lattice QCD calculations

2009/06/18 Y. G. Ma, talk @ SDU

宇宙的演化

大爆炸 夸克－胶子等离子体

中子，质子 轻原子核

原子 恒星 重元素

2009/06/18 Y. G. Ma, talk @ SDU

Phase Transition in Nuclei

Liquid Gas Phase Transition from cool nuclei to the full disassembly of nuclei Isis Data: 8-10GeV/c - , p+AuLabs: MSU-Miniball, TAMU-Nimrod, Indiana U-Isis, GANIL-Indra,GSI-Aladin, Catania-Chimera

Quark-Gluon Phase Transition ： from Hadronic Matter to QGPRHIC Detectors:

STAR, PHENIX, PHOBOS, BRAHMS

Recent results: dAu vs AuAu

Sciences, 22 Jan 2002

ISiS

STAR

Central Collisions130GeV/c Au+Au

Baryonic Potential B [MeV]

Ch

em

ical Tem

pera

ture

Tch

[M

eV

]

0

200

250

150

100

50

0 200 400 600 800 1000 1200

AGS

SIS

SPS

RHIC quark-gluon plasma

hadron gas

neutron stars

early universe

thermal freeze-out

deconfinementdeconfinementchiral restorationchiral restoration

Lattice QCD

atomic nuclei

2009/06/18 Y. G. Ma, talk @ SDUCGC GlasmaInitial

SingularitysQGP Hadron Gas

Theory Summary of QM2006By L. McLerran

RHIC & Cosmology

Art due to Tetsuo Hatsuda and Steffen Bass

(with some artistic interpretation)

2009/06/18 Y. G. Ma, talk @ SDU

T (MeV)

(N-Z)/

A?

V

P

Isothermes

spinodalregion

T

E tot

P constant

2009/06/18 Y. G. Ma, talk @ SDU

Collision Geometry

x

z

Non-central Collisions

Number of participants: number of incoming nucleons in the overlap regionNumber of binary collisions: number of inelastic nucleon-nucleon collisions

Charged particle multiplicity collision centralityReaction plane: x-z plane

Au + Au sNN = 200 GeV

2009/06/18 Y. G. Ma, talk @ SDU

The Phase Coexistence Curve

Ref: J. Elliott et al., Phys. Rev. Lett. 88 (2002) 042701

J.Natowitz, K. Hagel, Y.G. Ma et al., Phys Rev Lett 89, 212701 (2002);

Limiting Temperatures

Nucleonic MatterTc

Nuclear Matter Tc

2009/06/18 Y. G. Ma, talk @ SDU

CsI

Si

NIMROD

Electronics

马余刚在 Texas A&M 大学进行 47MeV/nucleon 40Ar+27Al, 48Ti and 58Ni合作实验并分析数据 , 并采用包含 / 不包含液汽相变的不同模型对 A~36核碎裂实验数据进行模拟，发现 E*/A ~ 5.6 MeV 时有原子核的液气相变产生。

2009/06/18 Y. G. Ma, talk @ SDU

Our experiment @ TAMU-NIMROD: Ar+Al, Ti and Ni @ 47AMeV

No plateau!No plateau!(E*~5.6MeV,Tc~8.3MeV)(E*~5.6MeV,Tc~8.3MeV)

2009/06/18 Y. G. Ma, talk @ SDU

最大涨落：临界行为charge, Zmax and kinetic energy spectra

=2 /

<Z

max

>

YGM et al., Phys. Rev C 71, 054606 (2005)

2009/06/18 Y. G. Ma, talk @ SDU

碎片电荷分布：幂指数分布（临界点）Experiment @ TAMU-NIMROD: Ar+Al, Ti and Ni @ 47AMeV

• Zqp

The minimum The minimum effeff ~ 2.31, close to the critical exponent of liquid gas phase ~ 2.31, close to the critical exponent of liquid gas phase transition universal class predicted by Fisher droplet model!transition universal class predicted by Fisher droplet model!

1 2 3 4 5 6 7 8 92

3

5.85.96.06.16.26.36.46.5

eff

E*/A (MeV)

Red lines: Fisher droplet

Power-Law fit: dN/dZ ~Z-eff

YGM et al., PRC 69, 031604 (R) (2004)

Fisher 的小液滴模型预言了液气相变时，碎片的质量或电荷分布应该遵循幂指数率，即 dN/dA A-, 并且此时最小 .

2009/06/18 Y. G. Ma, talk @ SDU

Zipf’s Law• Back to Linguistics

• Count number of words in a book (in English) and order the words by their frequency of appearance

• Find that the most frequent word appears twice as often as next most popular word, three times as often as 3rd most popular, and so on.

• Astonishing observation! G. K. Zipf, Human Behavior and the Principle of Least Effort

(Addisson-Wesley, Cambridge, MA, 1949)

1

21

41

61

81

101

121

141

161

181

201

1 21 41 61 81 101 121 141 161 181 201

Word Rankthe 1of 2

and 3a 4in 5to 6it 7is 8

was 9to 10i 11

for 12you 13he 14be 15

with 16on 17

that 18by 19at 20

1

21

41

61

81

101

121

141

161

181

201

1 21 41 61 81 101 121 141 161 181 201

fn 1

n

n

1.4f1fn

English Word Frequency

2009/06/18 Y. G. Ma, talk @ SDU

Nuclear Zipf’s Law• Zipf-type plot: • Zipf’s law (=1)

2009/06/18 Y. G. Ma, talk @ SDU

碎片从大到小等级分布： Zipf plot

Zipf law fit:

Zrank ~ rank-

Our Data: Zipf-law is satisfied around E*/A ~ 5.6 MeV/u

YGM, Phys. Rev. Lett. 83, 3617 (1999)

YGM et al., Phys. Rev C 71, 054606 (2005)

QP Data: Ar (+Ni)

Experiment @ TAMU-NIMROD

2009/06/18 Y. G. Ma, talk @ SDU

双模态（ Bimodality ） - 相变信号序参量：最大碎片电荷数

YGM et al., Phys. Rev C 71, 054606 (2005);

YGM et al., Nucl. Phys. A 749 (2005) 106c

Experiment @ TAMU-NIMROD

2009/06/18 Y. G. Ma, talk @ SDU

临界指数的决定 : , ,, YGM et al., Phys. Rev C 71, 054606 (2005)

2009/06/18 Y. G. Ma, talk @ SDU

轻核系统的临界行为

(1)碎片电荷分布的幂指数率 (2)最大涨落(3) 碎片分布的等级结构： Zipf’s 定律，双模态(4) 临界指数的决定(5) 量热曲线

统计物理的概念同样适合于微观的原子核体系！

2009/06/18 Y. G. Ma, talk @ SDU

研究夸克 - 胶子等离子体(QGP)

Baryonic Potential B [MeV]

Ch

em

ical Tem

pera

ture

Tch [

MeV

]

0

200

250

150

100

50

0 200 400 600 800 1000 1200

AGS

SIS

SPS

RHIC quark-gluon plasma

hadron gas

neutron stars

early universe

thermal freeze-out

deconfinementdeconfinementchiral restorationchiral restoration

Lattice QCD

atomic nuclei

LHC

Phase diagram of nuclear matter

2009/06/18 Y. G. Ma, talk @ SDU

Tool : Nucleus-Nucleus CollisionsColliding two nuclei we expect to create the QCD transition in lab.

Evolution of the system formed in Nucleus-Nucleus collisionsJ. D. Bjorken Physical Review D 27 (1983) 140

2009/06/18 Y. G. Ma, talk @ SDU

High-energy Nuclear Collisions

Initial Condition - initial scatterings - baryon transfer - ET production - parton dof

System Evolves - parton interaction - parton/hadron expansion

Bulk Freeze-out - hadron dof - interactions stop

jets

J/D

K, K*

p

d, HBT

elliptic flow velliptic flow v22

radial radial flowflowTT

Q2

time

partonic scatterings?early thermalization?

TTCC

TTchch

TTfofo

2009/06/18 Y. G. Ma, talk @ SDU

RHIC BRAHMSPHOBOS

PHENIXSTAR

AGS

TANDEMS

1 km

Animations by Mike Lisa

2009/06/18 Y. G. Ma, talk @ SDU

PHENIX – photons, leptons

测量单粒子谱及低动量粒子间的关联

在宽的膺快度范围（ 0<<4 ）及小立体角上测量它们的动量和横动量

大接收度，同时大接收度，同时 ,, 多观察量多观察量测量（强子） 精密磁谱仪测量（强子） 精密磁谱仪

2009/06/18 Y. G. Ma, talk @ SDU

STAR: TPC & MRPC-TOF

TPC dE/dx PID: pion/kaon: pT ~ 0.6 GeV/c; proton pT ~ 1.2 GeV/c

A new technology -Multi-gap Resistive Plate Chamber (MRPC), adopted from CERN-Alice

A prototype detector of time-of-flight (TOFr) was installed in Run3

One tray: ~ 0.3% of TPC coverage

Intrinsic timing resolution: ~ 85 pspion/kaon ID: pT ~ 1.7 GeV/cproton ID: pT ~ 3 GeV/c

2009/06/18 Y. G. Ma, talk @ SDU

MagnetMagnet

CoilsCoils

Central Central TriggerTriggerBarrel Barrel (CTB)(CTB)

ZCalZCal

Time Time Projection Projection

ChamberChamber(TPC)(TPC)

Year 2000Year 2000

Barrel EM Cal Barrel EM Cal (BEMC)(BEMC)

Silicon Vertex Silicon Vertex Tracker (SVT)Tracker (SVT)Silicon Strip Silicon Strip Detector (SSD)Detector (SSD)

ZDC-SMDZDC-SMD

FTPCFTPCEndcap EM CalEndcap EM CalFPDFPD

TOFp, TOFrTOFp, TOFr

Year 2001/2003Year 2001/20035. TOF(飞行时间谱仪 )

The Solenoidal Tracker at RHIC (STAR)

2009/06/18 Y. G. Ma, talk @ SDU

，， SDUSDU

2009/06/18 Y. G. Ma, talk @ SDU

Peripheral Events 周边碰撞

2009/06/18 Y. G. Ma, talk @ SDU

Au + Au Collisions at RHIC

STARSTAR

Central Events中心碰撞

(real-time Level 3)

2009/06/18 Y. G. Ma, talk @ SDU

The sQGP Energy density is high enough:

Very large energy loss of jets

The evidence is strong that one has made a system of quarks and gluons which is to a good to fair

approximation explained by a Quark Gluon Plasma

Some Highlights from RHIC Collaboration

Coalesence models reproduce v2 at intermediate pt.

Good agreement of “well thought out” hydro computations with radial and elliptic flow data

2009/06/18 Y. G. Ma, talk @ SDU

Quark Gas

Quark liquid

2009/06/18 Y. G. Ma, talk @ SDU

Elliptic flow

• Strong elliptic flow– Mass dependence signals common velocity– observed approaching hydro limit

• Modeled with hydro– Parton EoS + phase transition to hadron gas

2009/06/18 Y. G. Ma, talk @ SDU

20

Is suppression an initial or final state Is suppression an initial or final state

effect?effect?

Initial state? gluon saturation

Final state? partonic energy loss

How to discriminate? - Turn off final state - only initial state effect

⇒ d+Au collisions

“Control” Experiment

dAu

2009/06/18 Y. G. Ma, talk @ SDU

<Nbinary>/inelp+p

Nucleus-nucleus yield

Nuclear Modification Factor:

AAhadrons

leadingparticle suppressed

q

q

?

If R = 1 here, nothing “new”going on

A key probe, new at RHIC: hard scattering of quarks and gluons

2009/06/18 Y. G. Ma, talk @ SDU

A d+Au“control” experiment was been performed!

Results show:Observed suppressiondue to nature of (new)

produced matter !

not initial state effectsPedestal&flow subtracted

Run II AuAu results at full energy show strong suppression !

d+Au “control”data needed to distinguish between different interpretations

0 90 180 Degrees

d+Au

CentralAuAu

2009/06/18 Y. G. Ma, talk @ SDU

22

The Suppression is Final State EffectThe Suppression is Final State Effect

Strong suppression of high pT in Au + Au, indicating large energy loss of an initial parton in partonic matter(QGP)

2009/06/18 Y. G. Ma, talk @ SDU

STAR

PHENIX

Partonic collectivity: Particle Dependence of v2 and Quark coalescence picture

Baryon

Meson

Why saturation at intermediate pT ?Why different for baryon and meson flow?

Hadronization Scheme for Bulk Partonic Matter:

KS – 2 quark coalescence – 3 quark coalescencefrom the partonic matter surface?!V2/n versus pT/n indicates quark matter anisotropy !!

y

x

py

Px

22

22

xy

xy )(tan,2cos 12

x

y

p

pv

Time evolution

Pressure induced flow +Surface emission pattern +Final state re-scattering

coordinate-space-anisotropy momentum-space-anisotropy

2009/06/18 Y. G. Ma, talk @ SDU

Shear viscosity/entropy

2009/06/18 Y. G. Ma, talk @ SDU

What viscosity will do?

2009/06/18 Y. G. Ma, talk @ SDU

Extraction of η/s by viscous hydro.

How strong is the coupling ?How strong is the coupling ?Simple pQCD processes do not generate sufficient interaction strength. Navier-Stokes

type calculation of viscosity yield a near perfect liquidViscous force ~ 0. We have made a sQGP not the anticipated wQGP.

Simple pQCD processes do not generate sufficient interaction strength. Navier-Stokes type calculation of viscosity yield a near perfect liquid

Viscous force ~ 0. We have made a sQGP not the anticipated wQGP.

??

Experimental verification at RHICExperimental verification at RHIC

Lacey et al., PRL 98 (2007) 092301Lacey et al., PRL 98 (2007) 092301

The quantum limit has been reached at RHIC and hasbeen independently verified in several measurements

of collective effects

The quantum limit has been reached at RHIC and hasbeen independently verified in several measurements

of collective effects

RB, J.Phys.G35:044504 (2008)RB, J.Phys.G35:044504 (2008)

2009/06/18 Y. G. Ma, talk @ SDU

Shock wave searches in AA collisions

2009/06/18 Y. G. Ma, talk @ SDU

Mach cone shock waves?

Perfect fluid of hot and dense matter at RHIC: cS, supersonic jets, jet-quenching.RHIC appears to have all the conditions to generate Mach-cone shock waves.

Scheid, Muller, Greiner, Phys. Rev. Lett. 32, 741 (1974); Hofmann, Stoecker, Heinz, Scheid, Greiner, PRL 36, 88 (1976).

Many recent studies: Stoecker, nucl-th/0406018; Casalderrey-Solana, Shuryak, Teaney, hep-ph/0411315; Ruppert, Muller, hep-

ph/0503158; Chaudhuri, Heinz, nucl-th/0503028; Renk, Ruppert, PRC73 (06) 011901, Ma et al., PLB B 641 (2006) 362; PLB647 (2007) 122; PRC 76 (2007) 014904 ; nucl-th/0608050.…

near-sidetrigger

away-side jet axis

asso

c. h

adro

ns

v > cS012

3c

S t

2c

S t

cS

tM

zone of silence

zone ofaction

Mach cone angle Ɵ

speed of sound cS = sin(Ɵ)equation of state

2009/06/18 Y. G. Ma, talk @ SDU

Mach-like Structures

(4(4

NPA 774, 581 (2006)PRL 97, 052301 (2006)PHENIXPHENIX

2009/06/18 Y. G. Ma, talk @ SDU

discrimination by 3-particle correlation

Mediumaway

near

deflected jets

away

near

Medium

mach cone

Medium

away

near

di-jets

Need 3-particle correlation to discriminate different physics mechanisms.

0

0

π

π

Δ1

Δ2

Δ1

Δ2

0

π

0 π

0

π

0 π Δ1

Δ2

Δ1

Trigger

Δ2

2009/06/18 Y. G. Ma, talk @ SDU

G.L. Ma, S. Zhang, YGM et al., Phys Lett B 641, 362 (2006)G.L. Ma, YGM, S. Zhang et al., Phys Lett B 647, 122 (2007) S. Zhang, G.L.Ma, YGM et al., Phys. Rev. C 76, 014904 (2007)G. L. Ma, S. Zhang, YGM, J. Phys. G 34, S693 (2007)G.L. Ma, S. Zhang, YGM et al., Nucl Phys. A 783, 515c (2007)

2009/06/18 Y. G. Ma, talk @ SDU

Spin Physics Program

The Spin Structure of the Proton:

½ = ½ q + G + <L>

q up, down and strange quarksG gluonsL angular momentum of quarks and gluons

Experimentally: 1) total spin in quarks ~ 30% 2) sea quarks are polarized too 3) little info about the gluon polarization 4) even less know about <L> and how to measure <L>

2009/06/18 Y. G. Ma, talk @ SDU

Spin Rotators(transverse/longitudinal)

STAR IR

RHIC polarimeters

Siberian Snakes

Siberian Snakes

PHENIX IR

100 GeV beam proton beams

Each bunch filled with a distinct polarization state

Spin Rotators at STAR IR allow for transverse and longitudinal spin orientation

Bunch Xings every 107-214 ns

CNI polarimeters + Hydrogen Jet target provide run by run & absolute polarization

pp Run Year FOM=P4L 2002 2003 2004 2005

2006

< Polarization> % 15 30 40-45 45-50 60

Lmax [ 1030 s-1cm-2 ] 2 6 6 16 30

Lint [pb-1 ] at STAR

(Longitudinal/Transverse)

0 / 0.3 0.3 / 0.25 0.4 / 0 3.1 / 0.1 8.5 / 3.4,6.8

Relativistic Heavy Ion Collider World’s First Polarized Proton Collider

2009/06/18 Y. G. Ma, talk @ SDU

ALL 1

Pbeam2

N N

N N

G

AN 1

Pbeam

N N

N N

Physics AsymmetriesSingle Spin Asymmetries

Double Spin Asymmetries

Pbeam Required Accuracy ~5%Pbeam Required Accuracy ~5%

RHIC Beam Polarimetry common to all Experiments

Qinghua Xu, SDU

2009/06/18 Y. G. Ma, talk @ SDU

Global Polarization

L

Spin-orbital coupling quark polarization hadron polarization WRT reaction plane

Z.T. Liang and X.N. Wang, PRL 94, 102301 (05), PRL 96, 039901 (06), PLB 629,20 (05)

2009/06/1866

With respect to production plane, , K* may be slightly polarized in low pT

region.

Within current statistic, we have not observed a significant polarization for and K* with respect to reaction plane,

STAR PreliminarySTAR Preliminary

Spin alignment of vector mesons(φ,k*0) in Heavy-Ion Collisions at RHIC

J. H. Chen (SINAP) et al, PRC (R) （ 2008 ）

2009/06/18 Y. G. Ma, talk @ SDU

Detector Upgrade Contribution and Physics Results from Chinese STAR-TOF Group

Module construction, QA and calibration, Physics analysisModule construction, QA and calibration, Physics analysis

BNL, LBL, MEPI, NASA, UNAM, RICE, UCLA, UT-Austin, U. Washington, Yale

CCNU (Wuhan), IHEP (Beijing), IMP (Lanzhou), SINAP, Tsinghua, USTC

Electronics, tray assembly, andElectronics, tray assembly, and integrationintegration

&

Project supported by DOE(USA) & NSFC, CAS, MoST

2009/06/18 Y. G. Ma, talk @ SDU

Management of Chinese STAR-TOF Project

Y.

Tsinghua data analysis Q. Yue

IMP data analysisJ. Wang

Deputy managerJ. Cheng/Tsinghua

Deputy managerH.F. Chen/USTC

2009/06/18 Y. G. Ma, talk @ SDU

Performance of STAR-TOF prototypesTOFr Tray in STAR

W.J. Llope ， DOE TOF Review

TOFr5 for Runs 5 & 6

2009/06/1870

Hadron/Electron/muon PID capability

electrons

Clean electron PID can be obtained up to PT< 3 GeV/c. This is used to measure the semileptonic decay of open charm.(STAR Collaboration, PRL94(2005) 062301

L. Ruan, Z. Xu, X. Dong et al.

|1/β-1|<0.03

Hadron PID: (, K) ~1.6 GeV/c , p ~ 3 GeV/c.

STAR Collaboration, PLB616(2005)8

Nucl-ex/0607011, Chen Zhong, Y.F. Zhang, Zhangbu Xu et al.Significantly reduce the systematic uncertainty on the charm cross section measurement.

0.15<pT<0.25 GeV/c, DCA < 3 cm

2009/06/1871

STAR, PRL. 97 (2006) 152301

• particle spectra up to very high pT = 12 GeV/c.

• TOF: pT up to 5 GeV/c,important for coalescence region.

A PRL publication from TOF prototype

2009/06/18 Y. G. Ma, talk @ SDUAnother PRL publication from TOF prototype

2009/06/18 Y. G. Ma, talk @ SDU

Large elliptic flow (despite small σ) at low pTNCQ-scaling of v2 for pT > 2 GeV/c (similar to Ω (sss) )Reco. models describe data well

RCP critical confirmation of baryon-meson dependence of RHIC observablesScaling described by reco. models

J.H. Chen et al. (SINAP for STAR), PRL 99 (2007)112301

2009/06/18 Y. G. Ma, talk @ SDU

小结Two kinds phase transitions are explored with help of 4pi detectors and STAR detectors. LGPT and sQGP are discussed.

The advantages of new technology – MRPC: good timing resolution, high efficiency , cost effective large area Time of Flight detector.

Chinese STAR-TOF group has provided the prototype of TOF detectors which work well in STAR, and satisfy the requirements. In addition, important physics results have achieved. Chinese team will provide full TOF for STAR upgrade, more interesting physics is awaiting.

More Physics achievements are expected with Barrel TOF project!!!

2009/06/18 Y. G. Ma, talk @ SDU

For Future…

RHIC next planAndLHC

76

76

LQCD predicts a rapid transition from a hadron resonance gas to a quark-gluon plasma.

LQCD predicts a rapid transition from a hadron resonance gas to a quark-gluon plasma.

The location of the QCD Critical Point, if it exists, remains a matter for experiment The location of the QCD Critical Point, if it exists, remains a matter for experiment

STAR Collaboration is planning for initial beam energy scan in Run 10 (fall 2009)

Primary tool: search for anomalously large particle identified fluctuations with comprehensive particle identification for charged particles provided by TPC + TOFTPC + TOF

STAR Collaboration is planning for initial beam energy scan in Run 10 (fall 2009)

Primary tool: search for anomalously large particle identified fluctuations with comprehensive particle identification for charged particles provided by TPC + TOFTPC + TOF

Beam Energy Scan & QCD critical point searchBeam Energy Scan & QCD critical point search

77

77

• PID information for > 95% of kaons and

protons in the STAR acceptance

• Clean e± ID down to 0.2 GeV/c

• PID information for > 95% of kaons and

protons in the STAR acceptance

• Clean e± ID down to 0.2 GeV/c

/K separation to 1.6 GeV/c – 0.7 for TPC alone

(+K)/p to p = 3 GeV/c – 1.2 for TPC alone

Collaboration plan120 trays of MRPC modules which leverage

MRPC development at CERN (Crispin Williams et al) Development of HPTDC Chip

MRPC tech transfer and construction (contributed) in ChinaMRPC tech transfer and construction (contributed) in ChinaFully complete in time for run 10 (fall 2009)

Collaboration plantrays of MRPC modules which leverage 120

MRPC development at CERN (Crispin Williams et al)Development of HPTDC Chip

MRPC tech transfer and construction (contributed) in ChinaMRPC tech transfer and construction (contributed) in ChinaFully complete in time for run 10 (fall 2009)

Five “final item” trays in place and in STAR data stream nowFive “final item” trays in place and in STAR data stream now

2009/06/18 Y. G. Ma, talk @ SDU 78

LHC: Plasma Energy Density; Lifetime

Energy density expected to increase by factor ~ 2 – 3

ε0 = dN/dy <E>/ τ0 4πR2

Lifetime of QGP byFactor ~ 2 – 3

2009/06/18 Y. G. Ma, talk @ SDU 79

ALICE: An LHC Ion Collider Experiment at CERN-LHC

Size: 16 x 26 meters

Weight: 10,000 tonnes

2009/06/18 Y. G. Ma, talk @ SDU

The Heavy Ion Tracking Challenge

STARSTAR

NA49

LHC: dNch/dy = 2000 - 4000ALICE 'worst case' scenario:

dNch/dy = 8000

2009/06/18 Y. G. Ma, talk @ SDU

LHC Physics Program• Global properties

– Multiplicities, η distributions– Hadron ratios and spectra– Dilepton continuum, Direct photons

• Collective effects– Elliptic flows

• Fluctuations and critical behavior– Event-by-event particle spectra

• De-confinement– Charmonium, bottonium spectroscopy

• Chiral symmetry restoration– Neutral to charge ratio– Resonance decays

• Partonic energy loss in QGP– Jet quenching, high pT spectra– Open charm and beauty

⇛Hydrodynamics,

entropy density,

QCD Equation-of-State,

medium viscosity, ...

⇛ QCD crit

, Tcrit

,

Transport coefficients,Colour and mass dependence of energy loss

2009/06/18 Y. G. Ma, talk @ SDUAt Quark Matter 2006

2009/06/18 Y. G. Ma, talk @ SDU

Thank you for your attention

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