中高能重离子碰撞与核物质状态方程研究

张亚鹏; 孙志宇; 雍高产; 冯兆庆

doi:10.7498/aps.74.20241650

中高能重离子碰撞与核物质状态方程研究

1.
中国科学院近代物理研究所, 重离子科学与技术全国重点实验室, 兰州　730000
2.
中国科学院大学核科学与技术学院, 北京　100049
3.
华南理工大学物理与光电学院, 广州　510641

作者简介: E-mail: y.p.zhang@impcas.ac.cn .

通讯作者: E-mail: sunzhy@impcas.ac.cn;

中图分类号: 21.65.Mn, 25.70.-z, 29.20.db

Intermediate/high-energy heavy-ion collisions and nuclear matter equation of state

1.
State Key Laboratory of Heavy Ion Science and Technology, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
2.
School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
3.
School of Physics and Optoelectronics, South China University of Technology, Guangzhou 510641, China

Corresponding author: E-mail: sunzhy@impcas.ac.cn;

MSC: 21.65.Mn, 25.70.-z, 29.20.db

摘要: 核物质状态方程是对核物质体系在不同热力学或者外场条件下的宏观性质的描述, 它对理解微观强相互作用的理论——量子色动力学(QCD)、原子核性质、重离子碰撞动力学、致密天体内部结构、双中子星合并等具有重要意义. 重离子碰撞(HICs)是在实验室产生极端条件(如高温、高密、强磁场、强涡旋等)核物质的唯一手段, 不同碰撞能量的HICs为定量研究核物质在不同热力学条件下的性质提供了可能. 本文主要介绍当前核物质状态方程的研究现状, 并介绍HICs中对核物质状态方程敏感的基本可观测量、探索核物质状态的典型实验和结果. 展现包含有奇异强子核物质状态方程的研究进展, 并探讨未来可能的研究方向. 介绍国际上在建和正在运行的重离子加速器和实验谱仪的最新进展, 包括我国已经建成的兰州重离子加速器装置(HIRFL)和兰州重离子加速器装置-冷却储存环(HIRFL-CSR)、在建的强流重离子加速器装置(HIAF)和在建的低温高密核物质测量谱仪的研制进展, 并讨论未来基于我国大科学装置开展核物质状态方程实验研究的机遇与挑战.
- 核物质状态方程 /
- 重离子碰撞 /
- 兰州重离子加速器装置-冷却储存环(HIRFL-CSR) /
- 强流重离子加速器装置(HIAF)
Abstract: The equation of state (EoS) of nuclear matter is a description of the macroscopic properties of nuclear matter under different thermodynamic conditions or external fields, which is critical for understanding the theory of the strong interaction—quantum chromodynamics (QCD), the nature of nuclei, the dynamics of heavy-ion collisions (HICs), the internal structure of compact stars, the merger of binary neutron stars, and other physical phenomena. Heavy-ion collisions (HICs) are the only method in laboratories to create nuclear matter with extreme conditions such as high temperatures and high densities. HICs at different energy levels offer the possibility to quantitatively study the properties of nuclear matter under diverse thermodynamic conditions. This paper mainly presents the current research status of the EoS of nuclear matter and introduces the fundamental observables in HICs that are sensitive to the EoS, as well as the typical experiments and results used to explore the EoS. The progress in studying the EoS containing strangeness is also described and its possible research directions in the future are also discussed. The status and progress of worldwide heavy-ion accelerators and experimental spectrometers in the high-baryon density region are introduced, including China’s large-scale scientific facilities, i.e HIRFL-CSR and HIAF, as well as the CEE experiment. Additionally, the opportunities and challenges for experimental research on the EoS of nuclear matter in China are discussed.
- equation of state (EoS) /
- heavy-ion collisions /
- HIRFL-CSR /
- HIAF .

图 1 用温度、重子密度和同位旋不对称度表示的核物质相图. 图片更新自文献[8]

Figure 1. Nuclear matter phase diagram represented by temperature, baryon density and isospin asymmetry. Figure taken from Ref. [8]

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图 2 对称核物质和中子核物质状态方程随密度的变化, 图片更新自文献[29]

Figure 2. EoS of isospin symmetric nuclear matter and neutron matter as a function of the density, figure taken and updated from Ref. [29].

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图 3 地面重离子碰撞实验和天文观测提取到$ E_\text{sym}(\rho_0) $(a)和$ L_\text{sym}(\rho_0) $(b)的结果. 图(a)和图(b)均取自文献[24]

Figure 3. $ E_\text{sym}(\rho_0) $ (a) and $ L_\text{sym}(\rho_0) $ (b) extracted from terrestrial heavy-ion experiments and astrophysical observations respectively. Panel (a) and panel (b) both are taken from Ref. [24].

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图 4 重离子碰撞中的碰撞参数和反应平面示意图

Figure 4. Sketch of impact parameter and reaction plane in Heavy-ion collisions.

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图 5 UrQMD模型在仅考虑强子相情况下, 模拟0.2—12.8 GeV/u的对心Au+Au碰撞中的温度和密度关联图, 实线和虚线分别表示硬和软的状态方程. 图片取自文献[34]

Figure 5. Diagram of temperature and maximum density in central Au+Au collisions at 0.2–12.8 GeV/u simulated by the UrQMD model with hadron phase only. Figure taken from Ref. [34].

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图 6 直接流$ v_1 $和快度在$ y_{{\mathrm{cm}}} = 0 $的斜率与碰撞能量的关联图. 图片取自文献[36]

Figure 6. Slope of $ v_1 $ as a function of rapidity at $ y_{{\mathrm{cm}}} = 0 $ of proton versus collision energies. Figure taken from Ref. [36].

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图 7 质子椭圆流与碰撞能量的依赖关系. 图片取自文献[37]

Figure 7. Elliptic flow of proton as a function of collision energies, figure taken from Ref. [37].

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图 8 STAR实验测量的组分夸克数约化强子集体流与约化横能量的依赖关系. 图片取自文献[46]

Figure 8. Constitute quark number scaled elliptic flow of hadrons as a function of quark number scaled transverse energy measured by the STAR experiment. Figure taken from Ref. [46].

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图 9 对称核物质压强随密度变化的实验限制. 图片取自文献[34]

Figure 9. Pressure of the symmetric nuclear matter as a function of density constrained by experimental measurements. Figure taken from Ref. [34]

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图 10 KaoS实验测量$ {\mathrm{K}}^+ $介子在Au+Au和Cu+Cu碰撞中产额比随碰撞能量的变化, 来自输运模型IQMD和RQMD的硬EoS和软EoS分别用短线和点线表示. 图片取自文献[50]

Figure 10. Yield ratio of $ {\mathrm{K}}^+ $ in Au+Au and Cu+Cu collisions as a function of collision energy measured by the KaoS experiment. The hard and soft EoS from the transport models IQMD and RQMD are represented by dashed and dotted lines, respectively. Figure taken from Ref. [50].

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图 11 FOPI实验测量0.4, 1.0和1.5 GeV/u的Au+Au碰撞中质子和氘核的椭圆流随快度的变化, 基于IQMD模型硬EoS和软EoS理论计算结果分别用虚线和实线表示. 图片取自文献[56]

Figure 11. Elliptic flow of proton and deuteron as a function of rapidity in Au+Au collisions at 0.4, 1.0, and 1.5 GeV/u mesured by the FOPI experiment, red dashed line and black line represent the IQMD predictions with hard EoS and soft EoS respectively. Figure taken from Ref. [56].

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图 12 对称能$ E_{\text{sym}} $与密度的依赖关系, 其中不同的点来自不同的实验. 图片取自文献[34]

Figure 12. The symmetric energy $ E_{\text{sym}} $ as a function of nuclear matter density, symbols represent results obtained from different experiments. Figure taken from Ref. [34]

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图 13 (a) 30 MeV/u的Ar+Au反应中, 轻带电粒子的约化中子丰度随实验室角度的变化关系, 曲线为理论模型计算结果; (b)轻核约化中子丰度小角度区的下降斜率(红色区域)与理论计算(空心圆圈)的比较. 图片取自文献[58]

Figure 13. (a) In 30 meV/u Ar+Au reactions, $ Y_{{\mathrm{n, ex}}}/Y_{{\mathrm{p, CL}}} $ as a function of polar angle, curves are theoretical calculations; (b) comparison the slope of $ Y_{{\mathrm{n, ex}}}/Y_{{\mathrm{p, CL}}} $ in $ \theta_{{\mathrm{lab}}}<100^{\circ} $ from experiment (red band) and theoretical predictions (open circles). Figure taken from Ref. [58]

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图 14 PREX实验装置示意图. 图片取自文献[60]

Figure 14. Schematic draw of PREX-II experiment. Figure taken from Ref. [60]

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图 15 不同的实验和理论给出的对称能参数$ L_\text{sym}-J_\text{sym} $的限制, 黑色空心圈为PREX-II测量结果, 红色实线和虚线表示其他实验中提取的$ L_\text{sym} = (58.9\pm16 )$ MeV的中心值和误差. 图片更新自文献[63]

Figure 15. Constraints on symmetry energy parameters $ L_\text{sym}-J_\text{sym} $, open circle presents the results of PREX-II experiment, solid and dashed horizontal lines represent the central value and error of $ L_\text{sym} = (58.9\pm16 )$ MeV, respectively. Figure was taken and updated from Ref. [63].

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图 16 FOPI-LAND实验探测器布局图. 图片取自文献[64]

Figure 16. Detector layout of the FOPI-LAND experiment. Figure taken from Ref. [64]

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图 17 ASY-EOS实验探测器布局图, 图片取自文献[68]

Figure 17. ASY-EOS experiment detector layout, figure were taken from Ref. [68]

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图 18 400 MeV/u的Au+Au半中心碰撞(b < 7.5 fm)中ASY-EOS实验测量到的中子和带电粒子椭圆流的比值$ v_2^{\mathrm{n}}/v_2^{{\mathrm{ch}}} $和横动量的关联(黑色方框), 三角和圆分别代表UrQMD在硬($ \gamma = 1.5 $)和软($ \gamma = 0.5 $)对称能时计算结果, 实线是对理论计算结果做线性延拓, 得到与实验数据符合得最好时$ \gamma = 0.75\pm0.1 $. 图片取自文献[68]

Figure 18. Elliptic flow ratio of neutron and charged particle as a function of transverse momentum, in semi-central Au+Au collisions (b < 7.5 fm) at 400 MeV/u measured by ASY-EoS experiment. Triangles and squares are UrQMD predictions with hard ($ \gamma = 1.5 $) and soft ($ \gamma = 0.5 $) symmetry energy, solid line is the linear interpolation of predictions which can describe the data best, correspond to $ \gamma = 0.75\pm0.1 $. Figure taken from Ref. [68]

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图 19 FOPI实验测量400 MeV/u的核核中心碰撞中$ {\pi}^-/{\pi}^+ $产额比对碰撞系统N/Z的依赖(空心菱形)和IBUU04模型在x = 1.0 (软EoS)、0.5 (中等EoS)和0 (硬EoS)模拟结果比较, 图片取自文献[72]

Figure 19. $ {\pi}^-/{\pi}^+ $ yield ratio measured the FOPI experiment in central nucleus-nucleus collisions at 400 MeV/u as a function of N/Z ratio of the colliding systems (open diamonds), and compared simulation results from the IBUU04 model for x = 1.0 (soft EoS), 0.5 (medium EoS), and 0 (hard EoS). Figure taken from Ref. [72]

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图 20 HADES实验(方框)、FOPI实验(圆点)、Stream chamber(三角)和E895(五角星)测量到的约化π多重数与$ \langle {A}_\text{part}\rangle $的关系. 图片取自文献[81]

Figure 20. π multiplicity measured by HADES (squares), FOPI (filled circles), Stream chamber (triangles), and E895 experiment (star) as a function of $ \langle {A}_\text{part} \rangle $. Figure taken from Ref. [81]

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图 21 SπRIT实验装置图. 图片取自文献[84]

Figure 21. SπRIT experiment setup. Figure taken from Ref. [84]

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图 22 SπRIT实验中Tyoto-Array和前角区触发探测器 (KATANA)实物照片. 图片取自文献[87]

Figure 22. Photo of the Tyoto-Array and the KATANA detector of the SπRIT experiment. Figure taken from Ref. [87]

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图 23 (a) SπRIT实验测量270 MeV/u时, 不同Sn+Sn碰撞系统$ {\pi}^-/{\pi}^+ $产额比; (b)系统¹³²Sn+¹²⁴Sn和¹⁰⁸Sn+¹¹²Sn系统双$ \pi^-/\pi^+ $产额比; 7个输运模型计算结果用不同颜色标记. 图片取自文献[88]

Figure 23. (a) $ \pi^-/\pi^+ $ yield ratio measured by the SπRIT experiment in Sn+Sn collisions with different N/Z ratio; (b) double ${\pi}^-/{\pi}^+ $ yield ratio in ¹³²Sn+¹²⁴Sn and ¹⁰⁸Sn+¹¹²Sn, results from 7 transport models are marked by bands with different color. Figure taken from Ref. [88]

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图 24 中子星质量(M)和半径(R)的关系, 其中绿色区域为核物质, 红色区域代表在核物质基础上再加入$ {\Lambda}{\mathrm{N}} $相互作用后中子星的M-R关系, 其中考虑了两种都可以描述超核数据的YNN相互作用. 图片取自文献[96]

Figure 24. The relationship between the mass (M) and radius (R) of a neutron star, where the green region represents pure nuclear matter, and the red region shows the M-R relationship of neutron stars after incorporating ΛN interactions on top of the nuclear matter, considering two types of YNN interactions that can both describe hyper-nuclear data. Figure taken from Ref. [96]

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图 25 对称核物质(a)和中子核物质(b)中, 超子-核子(YN)和超子-核子-核子(YNN) 三体相互作用随密度的函数关系. 图片取自文献[99]

Figure 25. In symmetric nuclear matter (a) and pure neutron matter (b), the hyperon-nucleon (YN) and three-body hyperon-nucleon-nucleon (YNN) interactions as a function of the density. Figure taken from Ref. [99]

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图 26 超氚$ ^3_{\Lambda}\text{H} $产额随重离子碰撞能量的变化. 图片取自文献[101]

Figure 26. Production yields of hyper-triton $ ^3_{\Lambda}\text{H} $ as a function of colliding energies in HICs. Figure taken from Ref. [101]

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图 27 3 GeV Au+Au碰撞5%—40%碰撞中心度中$ ^3_{\Lambda}\text{H} $和$ ^4_{\Lambda}\text{H} $直接流与快度依赖关系. 图片取自文献[102]

Figure 27. Directed flow of $ ^3_{\Lambda}\text{H} $ and $ ^4_{\Lambda}\text{H} $ as a function of the rapidity at 3 GeV Au+Au collisions in 5%–40% centrality. Figure taken from Ref. [102]

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图 28 从能量为$ \sqrt{s_{{\mathrm{NN}}}} = 2—5020 $ GeV重离子碰撞数据中提取到的化学冻出温度(T)和重子化学势($ \mu_{\mathrm{B}} $). 图片取自文献[108]

Figure 28. Chemical freeze-out temperature (T) and baryon chemical potential ($ \mu_{\mathrm{B}} $) extracted from HICs with colliding energy $ \sqrt{s_{{\mathrm{NN}}}} = 2-5020 $ GeV. Figure taken from Ref. [108]

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图 29 FAIR装置上的CBM实验和HADES实验的探测器布局示意图. 图片取自文献[40]

Figure 29. Schematic diagram of the detector layout of the CBM experiment and the HADES experiment at the FAIR facility. Figure taken from Ref. [40]

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图 30 NICA装置上的MPD实验探测器布局示意图. 图片取自文献[41]

Figure 30. Schematic diagram of the detector layout of the MPD experiment at the NICA facility. Figure taken from Ref. [41]

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图 31 韩国RAON装置上的LAMPS实验探测器布局示意图. 图片取自文献[45]

Figure 31. Schematic diagram of the LAMPS experiment at the RAON facility. Figure taken from Ref. [45].

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图 32 HIRFL-CSR加速器布局示意图. 图片取自文献[119]

Figure 32. Schematic diagram of the HIRFL-CSR facility. Figure taken from Ref. [119]

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图 33 低温高密核物质测量谱仪探测器布局示意图

Figure 33. Schematic diagram of the CEE experiment.

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图 34 强流重离子加速器装置(HIAF)布局示意图. 图片取自文献[121]

Figure 34. Schematic diagram of the HIAF facility. Figure taken from Ref. [121].

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表 1 世界上重离子加速器与其典型实验, 基于文献[108]数据扩充

Table 1. Heavy-ion accelerator in the world and its typical Experiments, expanded based on data listed in Ref. [108]

Facility	$ \sqrt{s_{{\mathrm{NN}}}} $/GeV	Period	Experiments
Bevalac	2.0—2.7	1975-1993	EOS/et al.
SIS18	2.4—2.7	1990—now	FOPI/Hades/et al.
FRIB	1.9—2.1	>2025	AT-TPC$ ^* $
RIBF	1.9—2.1	1986—now	SπRIT
RAON	1.9—2.0	>2030	LAMPS
HIRFL	2.0—2.4	2008—now	CEE/ETE
Nuclotron	2.0—3.5	2000—now	BM@N
JPARC-HI	2.0—6.2	>2030	DHS
SIS100	2.7—5.0	>2029	CBM/Hades
NICA	2.7—11.0	>2025	BM@N/MPD
RHIC	3.0—200	2000—2025	STAR
SPS	4.5—17.3	1981—now	NA49/NA61/SHINE
AGS	2.7—4.8	2022—now	E895/et al.
HIAF	2.2—3.5	>2027	CEE+/CHNS
LHC	2760	2018—now	ALICE
LHC	72	>2027	LHCb/ALICE-FT

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8. 总　结

由于核物质状态方程是强相互作用粒子在不同热力学或者外部条件下的系统宏观量之间的表达, 这对于理解强相互作用的理论, 理解EoS相关的物理现象(如种子皮)、过程(如早期宇宙演化)或者对象(如中子星)的性质具有重要意义, 因此核物质状态方程研究是核物理研究的重大前沿课题之一. 重离子碰撞是实验室产生高密核物质的唯一手段, 本文主要从实验者角度介绍了实验室重离子碰撞运动学变量(观测量)与核物质状态方程的联系、核物质状态方程当前的研究现状和一些我们认为重要的结果, 并介绍了未来几年国际上在建实验装置的进展.

基于SIS18加速器和AGS加速器的实验数据给出2—4.5倍饱和密度对称核物质的状态方程偏软, 对应饱和密度处的不可压缩系数$ K_0 $的范围是(230 ± 20) MeV. 对于同位旋不对称核物质, 综合地面实验和天文中子星观测数据后得出的状态方程参数的差别仍然较大. 李宝安等给出在饱和密度处的对称能参数为: $ E_{\text{sym}}(\rho_0) = (31.6\pm2.7 )$ MeV, 斜率$ L_{\text{sym}} = (58.9\pm16 )$ MeV, $ K_{\text{sym}} = (-107\pm88) $ MeV. 基于$ {\pi}^-/{\pi}^+ $产额比所提取的对称能参数具有很强的模型依赖性, 有待输运模型发展来消除模型之间的不一致性. 基于Pb中子皮测量结果则要求非对称核物质在饱和密度处是硬的EoS. 实验上唯一中子的集体流测量来自FOPI-LAND实验的400 MeV/u的Au+Au碰撞, 实验结果结合TuQMD模型和UrQMD模型计算, 对于大于饱和密度区的对称能参数给出了一定约束. 在更高密度区, 对称能的限制则来自天文观测数据的中子星质量、中子星半径和双中子星合并中引力波. 因此, 在积累更多天文观测数据的同时, 积累更高质量、大统计量、包括中子测量的高重子密度区重离子碰撞实验数据就显得尤为重要. 实验上就必须要提高精度、计数率和实验效率(如CBM实验和ALICE实验将要采用的无触发系统). 这样的实验可以给出不同粒子的产额和集体流随碰撞中心度、横动量、快度等的变化. 这些多维度的数据自然就对输运模型提出了自洽描述的要求.

本文所讨论的研究状态方程的场景中, 比如高重子密度区重离子碰撞和双中子星并合中, 所产生的极端核物质的温度可能会达到约100 MeV, 而(1)式中的展开是在零温近似下的EoS表达, 一个自然的问题就是在有限温情况下核物质状态方程参数的取值, 甚至EoS的表达形式是否有效? 在重离子碰撞提取状态方程参数时, 输运模型中的EoS的行为与(1)式中的形式等价, 体系的温度效应(体系内粒子运动速度的分布)在输运模型中通过粒子之间微观相互作用自动产生. 通常一个合理的输运模型要求能够描述不同粒子的产额(化学温度)以及他们的横动量的分布(动力学温度), 因此本文讨论的EoS的参数在限温体系中的定义是一致的. 而在有些场景, 比如双中子星并合事件中, 采用输运过程来模拟双中子星并合的过程是不现实的, 这就需要在EoS的展开中除了密度、同位旋不对称度, 还需要考虑温度的贡献. 有限温情况下EoS依据密度、同位旋不对称、温度做泰勒展开的数学形式尚未达成共识, 最新关于此类展开尝试还在发展中, 如文献[123]. 除了前文讨论的EoS与密度、同位旋不对称度、温度、超子-核子相互作用的贡献, 核物质状态方程还可能依赖系统所处的外部条件, 如强磁场、强涡旋等, 相关研究的最新进展请参考文献[124]. 另外, 近些年我国研究人员在核核碰撞中粒子自旋效应的理论研究和实验研究中发挥了重要作用^[125–127], 这些研究表明, 重离子碰撞演化过程中自旋核手征效应或许能对核物质状态方程的研究提供新的自由度和实验可观测量. 2023年, 国内专家组织了关于高能重离子碰撞过程的自旋与手征效应最新研究进展的专刊^[128], 其中文献[129–131]讨论了粒子自旋效应在核物质状态方程中可能存在的效应. 这里需要指出的是, 虽然EoS可有不同的展开形式, 如多阶展开、多变量的展开等, 但是尝试提取所有高阶数的参数展开项系数在实验上是不现实的. 如何基于EoS的参数化形式, 来给出更简洁或者更解析的EoS表达, 将是人们理解强相互作用性质的重大突破, 当前迅速发展的人工智能或许能为解决这个问题发挥关键作用.

未来几年, 在高重子数密度区重离子碰撞研究上会有新的实验数据陆续公布, 比如来自SISI8上运行的HADES实验、NICA装置上的BM@N实验、HIRFL装置上的CEE实验、STAR-BESII的固定靶实验数据等, 这些高精度且多维度(比如产额、集体流等随中心度、快度、横动量等)的实验数据, 将对核物质状态方程在高密区的行为产生强有力的约束. 随着高质量的实验数据陆续公布和TEMP合作组推进的输运模型发展计划, 输运模型之间的差异将逐渐缩小. 这对于提取核物质状态的参数具有至关重要的意义. 我国在建的基于HIRFL-CSR装置的CEE谱仪将于2025年开始运行, 标志着我国可以自主开展1—2倍饱和密度区、温度约为40 MeV的核物质性质研究: 包括核物质状态方程、相结构、短程关联等. 将于2025年建成的HIAF装置, 为研究极端核物质性质相关的前沿课题——包含奇异夸克自由度的核物质状态方程、强子的介质效应、超核极化、发现新超核和多超子超核、核介质依赖YN相互作用、自旋效应等尚未被人们充分认识的领域提供绝佳研究机遇.

参考文献 (131)

中高能重离子碰撞与核物质状态方程研究

作者简介: E-mail: y.p.zhang@impcas.ac.cn .

通讯作者: E-mail: sunzhy@impcas.ac.cn;

Intermediate/high-energy heavy-ion collisions and nuclear matter equation of state

Corresponding author: E-mail: sunzhy@impcas.ac.cn;

计量

中高能重离子碰撞与核物质状态方程研究

通讯作者: E-mail: sunzhy@impcas.ac.cn;

作者简介: E-mail: y.p.zhang@impcas.ac.cn
1. 中国科学院近代物理研究所, 重离子科学与技术全国重点实验室, 兰州　730000

2. 中国科学院大学核科学与技术学院, 北京　100049

3. 华南理工大学物理与光电学院, 广州　510641

English Abstract

Intermediate/high-energy heavy-ion collisions and nuclear matter equation of state

Corresponding author: E-mail: sunzhy@impcas.ac.cn;

全文HTML

4.1. 对称核物质状态方程相关的典型实验

4.1.1. $ {\mathrm{K}}^+ $介子在SIS18能区的产生

4.1.2. FOPI实验中的轻核集体流测量

4.2. 重离子碰撞和中子皮测量实验研究对称能进展

4.2.1. 费米能区核反应与低密区对称能

4.2.2. 中子皮厚度测量与饱和密度区对称能

4.2.3. 中子集体流研究高密区对称能进展

4.2.3.1. FOPI-LAND实验

4.2.3.2. ASY-EoS实验

4.2.4. 利用$ {\pi}^-/{\pi}^+ $产额比研究高密区对称能进展

4.2.4.1. FOPI实验的π产额比的测量

4.2.4.2. $ {\mathrm{S}}{{\pi}}{\mathrm{RIT}} $实验测量π产额比

6.1. 德国FAIR装置和CBM实验

6.2. 俄罗斯NICA装置和BM@N/MPD实验

6.3. 韩国RAON装置和LAMPS实验

7.1. 兰州重离子加速器-冷却储存环(HIRFL-CSR)和CEE实验

7.2. 强流重离子加速器装置(HIAF)

目录

中高能重离子碰撞与核物质状态方程研究

作者简介: E-mail: y.p.zhang@impcas.ac.cn .

通讯作者: E-mail: sunzhy@impcas.ac.cn;

Intermediate/high-energy heavy-ion collisions and nuclear matter equation of state

Corresponding author: E-mail: sunzhy@impcas.ac.cn;

计量

出版历程

中高能重离子碰撞与核物质状态方程研究

通讯作者: E-mail: sunzhy@impcas.ac.cn;

作者简介: E-mail: y.p.zhang@impcas.ac.cn 1. 中国科学院近代物理研究所, 重离子科学与技术全国重点实验室, 兰州 730000 2. 中国科学院大学核科学与技术学院, 北京 100049 3. 华南理工大学物理与光电学院, 广州 510641

English Abstract

Intermediate/high-energy heavy-ion collisions and nuclear matter equation of state

Corresponding author: E-mail: sunzhy@impcas.ac.cn;

全文HTML

4.1. 对称核物质状态方程相关的典型实验

4.1.1. $ {\mathrm{K}}^+ $介子在SIS18能区的产生

4.1.2. FOPI实验中的轻核集体流测量

4.2. 重离子碰撞和中子皮测量实验研究对称能进展

4.2.1. 费米能区核反应与低密区对称能

4.2.2. 中子皮厚度测量与饱和密度区对称能

4.2.3. 中子集体流研究高密区对称能进展

4.2.3.1. FOPI-LAND实验

4.2.3.2. ASY-EoS实验

4.2.4. 利用$ {\pi}^-/{\pi}^+ $产额比研究高密区对称能进展

4.2.4.1. FOPI实验的π产额比的测量

4.2.4.2. $ {\mathrm{S}}{{\pi}}{\mathrm{RIT}} $实验测量π产额比

6.1. 德国FAIR装置和CBM实验

6.2. 俄罗斯NICA装置和BM@N/MPD实验

6.3. 韩国RAON装置和LAMPS实验

7.1. 兰州重离子加速器-冷却储存环(HIRFL-CSR)和CEE实验

7.2. 强流重离子加速器装置(HIAF)

目录

作者简介: E-mail: y.p.zhang@impcas.ac.cn
1. 中国科学院近代物理研究所, 重离子科学与技术全国重点实验室, 兰州　730000

2. 中国科学院大学核科学与技术学院, 北京　100049

3. 华南理工大学物理与光电学院, 广州　510641