QCD相变与高能核碰撞-量子分子动力学之家

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Pt Dependence of the Two Production Mechanisms Initial production through hard process controls high pt, regeneration in hot medium is important at low pt.
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Prediction on Centrality Distribution at LHC
PBM group Rapp group
Tsinghua Group
from talk by J.Wiechula at Hard Probe 2012
the band is due to the uncertainty in charm quark production cross section
不是圈图越多越好，有时图多了还破坏对称性。 ●超出平均场（按照动量扩展） 泛函重整化群（ FRG）
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泛函重整化群(FRG)
J. Berges H. Gies D. F. Litim N. Tetradis C. Wetterich …
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FRG for SU(3) Linear Sigma Model
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中心对称性 手征对称性 同位旋对称性 色对称性
退禁闭相变 手征相变 π超流相变 色超导相变
强子----QGP 手征凝聚 π凝聚 双夸克凝聚
T，μB T，μ μI μB
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1. Going beyond Mean Field with FRG
based on our recent papers: 1) Gaoqing Cao, Lianyi He, Pengfei Zhuang. Phys.Rev. A87 (2013) 013613 2) Yin Jiang, Pengfei Zhuang, Phys.Rev. D86 (2012) 105016 3) Shijun Mao, Pengfei Zhuang, Phys.Rev. D86 (2012) 097502 4) Chengfu Mu, Yin Jiang, Pengfei Zhuang, Yuxin Liu, Phys.Rev . D85 (2012) 014033 5) Yin Jiang, Ke Ren, Tao Xia, Pengfei Zhuang, Eur.Phys.J. C71 (2011) 1822 6) Lianyi He, Pengfei Zhuang, Phys.Rev . B83 (2011) 174504 7) Yin Jiang, Pengfei Zhuang, Phys.Rev. C83 (2011) 038201
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A Hard Probe of QGP Matsui and Satz, 1987: charmonia as a probe of QGP formation in heavy ion collisions. dissociation temperature from non-relativistic potential model :
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Beyond Mean Field
QCD物态理论：
●Lattice（有限温度，零重子数密度） ●平均场 （量子系统→经典系统，多体问题 →单体问题） ●超出平均场（按照圈图展开） ♠高斯近似（只包含二次型量子涨落 ,单圈图） ♠一类图型的无穷求和（ RPA，HTL，……） 例如NJL模型中的介子传播子
Initial and regeneration fractions for J/Ψ in central Pb+Pb collihsions at LHC energy
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Pt Distribution at SPS and RHIC
Theory Prediction 2006
Experimental Data 2011
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Experimantal Data from ALICE
from talk by PBM at XQCD2012
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Double Ratio and B Decay Contribution
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ቤተ መጻሕፍቲ ባይዱ
Conclusions 1) FRG, an effective method to include quantum fluctuations in the study of QCD phase transitions. 2) Quarkonium TMD, a more sensitive probe of QGP.
from talk by PBM at NN2012
remarkable v2 due to important regeneration !
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A New Nuclear Modification Factor
rAA =
Theory Prediction 2010
pt2 pt2
AA pp
rAA > 1 at SPS by Cronin effect
both initial production and regeneration suffer from dissociation !
● cold nuclear matter effects on the initial quarkonium distribution and the charm quark distribution 14
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波函数重整化
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介子谱
考虑手征极限： 有限温度时,平均场和自洽的Hatree近似破坏Nambu-Goldstone 定理,但能解析证明FRG保证了手征对称性。
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2. Probing QGP by Quarkonium TMD
based on our recent papers: 1) Xingyu Guo, Shuzhe Shi, Pengfei Zhuang, Phys.Lett. B718 (2012) 143-146 2) Baoyi Chen, Kai Zhou, Pengfei Zhuang, Phys.Rev. C86 (2012) 034906 3) B. Kampfer, R.Rapp,……P.Zhuang, Lect. Notes Phys. 814 (2011) 335-529 4) Jian Deng, Qun Wang, Nu Xu, Pengfei Zhuang, Phys.Lett . B701 (2011) 581-586 5) Yunpeng Liu, Baoyi Chen, Nu Xu, Pengfei Zhuang, Phys.Lett . B697 (2011) 32-36 6) Kai Zhou, Nu Xu, Pengfei Zhuang, Nucl. Phys . A834 (2010) 249C-252C 7) Yunpeng Liu, Nu Xu, Pengfei Zhuang, Nucl. Phys . A834 (2010) 317C-319C 8) Yunpeng Liu, Zhen Qu, Nu Xu, Pengfei Zhuang, J.Phys . G37 (2010) 075110
QCD 相变与高能核碰撞
庄鹏飞 （清华大学物理系）
1. Going beyond Mean Field with FRG 2. Probing QGP by Quarkonium TMD
全国核反应会议2013， 深圳
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QCD相变与高能核碰撞
a a Ta )ψ − Faµν Fµν 量子色动力学(QCD)： LQCD = ψ (iγ µ ∂ µ − mq − gγ µ Aµ
latticelatticelatticelatticelatticelatticelatticelattice有限温度零重子数密度有限温度零重子数密度有限温度零重子数密度有限温度零重子数密度有限温度零重子数密度有限温度零重子数密度有限温度零重子数密度有限温度零重子数密度平均场平均场平均场平均场平均场平均场平均场平均场量子系统量子系统量子系统量子系统量子系统量子系统量子系统量子系统经典系统多体问题经典系统多体问题经典系统多体问题经典系统多体问题经典系统多体问题经典系统多体问题经典系统多体问题经典系统多体问题单体问题单体问题单体问题单体问题单体问题单体问题单体问题单体问题超出平均场按照圈图开超出平均场按照圈图开超出平均场按照圈图开超出平均场按照圈图开超出平均场按照圈图开超出平均场按照圈图开超出平均场按照圈图开超出平均场按照圈图开????????高斯近似只包含二次型量子涨落高斯近似只包含二
relativistic correction :
≈ 10%
sequential suppression:
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Nuclear Modification Factor R AA
RAA
N AA = N pp N coll
R AA < 1 at SPS, RHIC and LHC, and the trend is similar. momentum distribution should be more sensitive to the nature of the medium !
rAA ≈ 1 at RHIC by competition
between initial production and regeneration
rAA < 1 at LHC by dominant
regeneration
for prompt J/ψs at 5.5 TeV in mid rapidity
Dissociation and Regeneration Rate
J /ψ ( ϒ) + g → Q + Q
● gluon dissociation cross section calculated by OPE (Bhanot, Peskin,1999):
σ ( pψ , pg )
● at finite temperature, we use the classical relation
A Full Transport Approach
● medium evolution
∂ µT µν = 0,
∂ µ n µ = 0 + equation of state
● hot nuclear matter effects on quarkonium production
α: dissociation β: regeneration
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Prediction on Pt Distribution at LHC
0-90%
from talk by R.Arnaldi at QM2012
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Prediction on Elliptic flow at LHC
Theory Prediction 2010 5.5 TeV b=7.8 fm prompt J/ψ no shadowing
σ ( pψ , pg , T ) =
r 2 (T ) r (0)
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σ ( pψ , pg )
r 2 (T ) is calculated through the
Schroedinger equation
● J/Ψ dissociation rate
● regeneration rate is determined by the detailed balance