合作单位 北大、华师、近物所 科大、上海 所、兰大、山大
DESCRIPTION
第十四届全国核结构大会 2012.4.12-16 ,湖州, 浙江. HIRFL-CSR 上低温高密核物质性质 研究计划 肖志刚 1 For CEE pre-Collaboration 1 清华大学物理系. 合作单位 北大、华师、近物所 科大、上海 所、兰大、山大. 内容 物理背景 CEE 的概念性设计 现状与计划 小结. 早期宇宙. T(MeV). LHC. Q G P. RHIC. SPS. 100. AGS. 强子气体. SIS. CSR. 10. 气态. 液态. 中子星. B GeV. 0.2. - PowerPoint PPT PresentationTRANSCRIPT
合作单位北大、华师、近物所科大、上海所、兰大、山大
第十四届全国核结构大会2012.4.12-16,湖州, 浙江
HIRFL-CSR上低温高密核物质性质研究计划
肖志刚 1
For CEE pre-Collaboration1 清华大学物理系
核物质相图
0.2
10
100
0.4 0.6 0.8 1.0 1.2 1.4 B GeV
T(MeV)
中子星液态气态
强子气体
Q G P
早期宇宙LHC
RHIC
SPS
AGS
SIS
CSR
核物质性质研究的关键性问题 :寻找具有参加子自由度的物质形态理解夸克物质、强子物质与核物质的不同性质理解上述三种物质状态之间的相变过程
Symmetry Energy:
(N-Z)
E
Energy cost to convert protons to neutrons in nuclear medium
...
3...
16218)()(),( 23
22
sym2
0 LEaEEE symV
:Compressibility
Esym
Revisit FOPI -/+ data with IBUU04
Z.G. Xiao, B.A. Li et al., Phys. Rev. Lett. 102 (2009) 062502A rather soft nuclear symmetry energy is more favored by FOPI data!!!
Measurement at sub GeV/u energy range helps to resolve the Esym()!
IBUU04:
What will be new ? I
What is missing is the forward region, particularly for the isospin sector in EOS study.
This is what CEE will focus on!
Well studied: Mass resolved phase space well covered at midrapidity with FOPI, yielding lots of physical outputs
1 Esym via -/+, and 3He/t
F. Fu, XZG et al., PLB666(2008)359
Advantages of pion observables at HIRFL-CSR:
Density as high as 2~30 , varying rapidly with beam energy;
Maximum stopping, maximum sensitivity on the EOS
NOT influenced by the problem of clustering in transport
Most copious produced, copious information of isospin effect;
……
What will be new ? I
What will be new ? I
Nuclear Stopping Power is maximized at HIRFL-CSR region, resulting in best sensitivity of the physical observable on the EOS of cold dense nuclear matter.
Sensitivity: S= (-/+ )x=1 /(-/+ )x=0
Degree of IF: (-/+ )tran- (-/+ )isob
What will be new ? II
What is missing is the forward region, particularly for the isospin sector in EOS study.
This is what CEE will focus on!
Well studied: Mass resolved phase space well covered at midrapidity with FOPI, yielding lots of physical outputs
1 Esym via -/+, and 3He/t
What will be new ? II
What is missing is the forward region, particularly for the isospin sector in EOS study.
This is what CEE will focus on!
Well studied: Mass resolved phase space well covered at midrapidity, yielding lots of physical outputs
1 Esym via -/+, and 3He/t
What will be new ? II
2 Isospin Tracing
Y(0)=Y/Ycm-1
Zr+Zr (less proton)
Zr+Ru
Ru+Ru (more proton)
Ru+Zr
To Make use of HIRFL-CSR heavy ion beamsN
CSRm
CSRe
SFC
SSC
SFC: 10 AMeV (H.I.), 17~35 MeV (p)SSC: 100 AMeV (H.I.), 110 MeV (p)CSRm: 1000 AMeV (H.I.), 2.8 GeV (p)
RIBLL1: RIBs at tens of AMeVRIBLL2: RIBs at hundreds of A MeVCSRe: storage ring with deceleration
RIB
LL
2
RIB
LL
1
CEE 磁铁 MWDC 硅像素和硅微条探测器 ZDC TOF ( T0, iTOF和MRPC) FEE/DAQ
• 2011年 7月 25日,第一次 Pre-CEE meeting• 2012年 2月 7日, 第二次 Pre-CEE meeting
DipoleMWDC MRPC
ZDC
STA
T0 Target
合作单位北大、华师、近物所科大、上海所、兰大、山大
(Test Beam)
• C+C @ 200,600 MeV/u• Three MWPC tracking• 12 TOF Strips + Start• 1 Neutron Wall• Inclusive • B~0.4T, reversible
Target
Outcome of the test beam run12C+12C 600AMeV
P+-
1) Tracks reconstructed well
2) Pion ratio ~ 1 in C+C
3) Limited electronics, detector resolution and Heavy background …
4) Systematic error not controlled
Full simulation and preparation for further experiment ongoing.
MWDC R&D
Dimension(cm) 114×76×13 98×8613 64×49×13
Sensitive Size (cm) 96×50 80×60 48×32
Anode Layers 6 6 6
Max. Drift Len. 5mm 5mm 5mm
Position Resolution: = 200 ~ 260mMIP Efficiency 95% ~ 97%,Max. Rate : 104 HZ/wire
1GeV/u 以下的重离子碰撞,是研究核物质状态方程的理想手段。冷致密核物质,可以在这一能区形成。 提出了 CEE的概念性设计,各个工作小组正在致力于完善各个子系统的设计和方案。
小结
期待大家的关注和支持!Thank you !