晕核和推广的Glauber理论

简要介绍了中子晕和质子晕研究的最新实验进展,同时,讨论了近年来发展的同位旋,能量有关的具有晕核结构的Glauber理论及它在描述晕核与核散射时的重要性.The development of new experiments for neutron (or proton) halo is briefly described, while the isospin and energy dependence of Glauber theory and its importance in describing halo nuclei-nucleus scattering are discussed.     

P同位素的质子滴线核研究

研究了在相对论平均场近似下P同位素的滴线核的性质,首先在理论上探讨了25P作为P的滴线核存在的可能性及其可能具有的质子晕结构,然后给出了在兰州放射性束流装置上25P的实验鉴别结果. Great progress was made on the study of P isotope both in theory and in experiments, but the final conclusion about the dripline of P isotope has not been made. In this article the properties of P isotope was studied in the frame work of relativistic mean field (RMF). First the probability of 25P as the dripline nuclei of P isotope and the proton halo structure of 25P was discussed, and then the RIBLL experiental result of 25P is presented.     

奇异核特性及相关反应研究

论述了晕核,尤其是质子晕核的特性及实验研究．探讨了放射性核引起的转移反应以及晕核的近库仑位垒熔合反应． The properties of halo nuclei, especially proton halo nuclei and their experimental researches have been reviewed. The transfer reactions induced by radioactive beams and near barrier fusion with halo nucleus are discussed.     

镜像核13N-13C 和15N-15O中的激发态晕或皮(英文)

用非线性相对论平均场对两对镜像核13N-13C 和15N-15O进行了研究. 发现无论在基态还是激发态， 用两套参数所得的结合能都跟实验值很接近. 计算结果显示13N的第一激发态（2s1/2）和第三激发态（1d5/2）各存在一个非束缚的质子晕， 而13C的第三激发态（1d5/2）存在一个弱束缚的中子皮. 另外研究表明, 在另一对镜像核15N-15O的第二激发态（2s1/2）和第一激发态（2s1/2）分别存在一个中子晕和质子皮. Properties of two pairs of mirror nuclei 13N-13C and15N-15O are investigated by using the nonlinear relativistic mean field theory. It is found that all the calculated binding energies with two different parameter sets are very close to the experimental ones for both the ground states and the excited states. The calculations show that the first excited state (2s1/2) and the third excited state (1d5/2) in 13N are both unbound resonances with proton halo structure, whereas the third excited state (1d5/2) in 13C is weakly bound with a neutron skin. It is also predicted that there has a proton halo in the second excited state (2s1/2) of 15N as well as a neutron skin in the first excited state (2s1/2) of 15O.     

放射性束装置给核结构研究带来的新机遇

利用放射性束装置所提供的高强度和高分辨率的短寿命核束流可达到核中质比的极端值 ,新的现象 ,如中子晕、质子晕、中子皮、质子皮、壳的减弱或消失 ,以及在滴线附近对力的重要性和核物质中质子 -中子对的新超导相的可能存在等不断涌现 .对这些现象进行研究和理解 ,然后回到实验上较易达到的稳定区核去检验人们的理解 ,会对进一步研究核结构、核合成、核天文和自然界基本对称性提供新的机遇 .By making use of the facility for radioactive beams which would be able to supply intense high resolution beams of short lived (radioactive) nuclei, the neutron proton ratio can be extended to extreme values, where some new phenomena such as neutron halo, proton halo, neutron skin, proton skin, growing evidence of the fragility or disappearance of shell structure far from stability, the importance of pairing correlation near drip line, and the possible existence of new superconducting phases of...     

Possible Experimental Evidence of a Moderate Proton Halo in ^29S

The total reaction cross sections (TRCSs) of^29S ^28Si have been measured at intermediate energies. An obvious enhancement in TRCS of ^29S is observed as compared with its neighbouring nuclei. The TRCSs of ^29S ^28Si arecal culated with the modified Glauber theory in the optical limit and few-body approaches. The different factor d as a possible measure of halo appearance is deduced from the experimental and theoretical data. It is well accepted that ^27p is a proton halo nucleus. Although not as anomalous as ^27p, the different factor d of ^29S is obviously larger than that of its neighbouring isotones of N = 13. This result indicates that a moderate proton halo may exist in ~9S nucleus. We calculate the total reaction cross sections for ~9S with the modified Glaubertheory as a function of incident energy and compare the results with those for 2rSi which is a core nucleus 0f29S.The measured TRCSs of 27Si4-2SSi can be described to be satisfactory by the modified Glauber theory of theoptical limit approach. Although a diffused nuclear density distribution is used, the theories still inadequatelypredict the experimental TRCSs of 29S4-2SSi, which further indicates the possibility of proton halo in 29S.     

Neutron halos in the excited states for N=127 isotones

Properties of the ground states and the excited states of N=127 isotones are investigated by using the nonlinear relativistic mean field theory with the interactions PK1. By analyzing the rms of proton and neutron, the single particle energies of valence nucleon and the density distributions of neutron, proton and the last neutron, it can be found that there exists a neutron halo in the excited states of 3d5/2, 4s1/2 and 3d3/2 in 209Pb. It is also predicted that there exists a neutron halo in the excited states of 3d5/2, 4s1/2 and 3d3/2 in 207Hg, 208Tl, 210Bi and 211Po.     

医用质子和12C离子束的物理性质研究

质子和重离子在现代放射治疗手段中已起着不可替代的作用， 这主要取决于其独特的物理性质。 利用一步过程和两步过程的物理模型解释了离子能量损失的机制， 同时结合Geant4软件包模拟质子和12C在水中的运输过程， 研究了离子束的物理性质， 并讨论了计算的结果， 说明了质子和12C在医学中应用的优缺点。 Depending on their unique physical properties， proton and heavy ions have taken an irreplaceable role in modern means of tumor treatment. One step process and two step process physical models were employed to explain the mechanism of ion energy loss. The transport process of proton and 12C in water was simulated by Geant4 toolkit to study the physical properties of ion beam. The calculation results were discussed， which showed the advantages and disadvantages of proton and 12C in the medical application.     

Neutron halos in the excited states for N=127 isotones

Properties of the ground states and the excited states of N=127 isotones are investigated by using the nonlinear relativistic mean field theory with the interactions PK1. By analyzing the rms of proton and neutron, the single particle energies of valence nucleon and the density distributions of neutron, proton and the last neutron, it can be found that there exists a neutron halo in the excited states of 3d5/2, 4s1/2 and 3d3/2 in ²⁰⁹Pb. It is also predicted that there exists a neutron halo in the excited states of 3d5/2, 4s1/2 and 3d3/2 in ²⁰⁷Hg, ²⁰⁸Tl, ²¹⁰Bi and ²¹¹Po.     

Probe the 2s（1/2） and 1d（3/2） state level inversion with electron-nucleus scattering

The neutron-rich even-even nuclei^26–40Mg,^28–46Si,^30–48S, and ^32–56Ar are calculated with the RMF model and the phase-shift electron scattering method. Results show that level inversion of the 2s1/2 and 1d3/2 proton states may occur for the magnesium, silicon, sulphur, and argon isotopes with more neutrons away from the stability line. Calculations show that the variation of the central charge densities for30–48S, and32–56Ar are very sensitive to the 2s1/2 and 1d3/2 proton state level inversion, and the level inversion can lead to a large measurable central charge depletion to the charge density distributions for the neutron-rich isotopes. Calculations also show that the charge density diferences between the isotopes with and without central charge depletion can reveal not only the level inversion of the 2s1/2 and 1d3/2 proton states but also the behavior of the proton wave functions of both states. The results can provide references for the possible study of the nuclear level inversion and nuclear bubble phenomenon with electron scattering of short-lived nuclei at RIKEN or/and GSI in the future. In addition, direct nuclear reaction 44S（n, d）43P or44S（3H, α）43P might also be a possible way to study the 2s1/2 and 1d3/2 proton state level inversion.     

相对论和非相对论理论模型研究奇异核的性质

采用相对论和非相对论理论模型可描述奇异核的性质 .相对论平均场理论预言了2 6,2 7,2 8P存在一个质子晕 ,而27,28,29S存在两个质子晕 .最近 ,MSU的最新的实验发现了2 6,2 7,2 8P核存在一个质子晕.采用相对论 Hartree- Fock理论研究了 Fock项和矢量介子对奇异核性质的贡献,研究表明交换项和矢量介子对非常丰中子核性质的影响非常不同于对稳定线附近核性质的影响.同时,采用形变的Hartree- Fock- Bogoliubov理论研究了某些轻核同位素链的性质和形变.     

Relativistic mean-field study on proton skins and proton halos in exotic nuclei

We investigate the ground state properties of proton-rich nuclei in the framework of the relativistic mean-field model. Calculations show that the experimental proton halo in the nuclei ^26,27,28P can be reproduced by the model. The proton halos can appear in proton-rich nuclei because the total nuclear potential is attractive up to the radial distance r ≈ 5.5 fm. But the size of proton halos is finite due to the limitation of the Coulomb potential barrier. The mean-square radius of a halo proton is not very sensitive to the separation energy of the last proton in some very proton-rich nuclei due to the effect of the Coulomb barrier. This behavior is different from the case of a neutron halo where the mean-square radius of a halo neutron is inversely proportional to the separation energy of the last halo neutron. We have also analysed the differences of the relativistic mean-field potentials of ²⁵Al and ²⁶P and found that the isovector potential from the p meson has an important effect on the differences.     

单粒子势模型下价核子的密度分布

依据实验事实，利用单粒子势模型，计算了一些核态外层价核子的密度分布.计算给出了价核子在核外部分布的概率和贡献，以此作为晕核态的判断标准.通过研究均方根半径随结合能变化的规律，指出了晕核态存在的条件，尤其是质子晕核态存在的条件.这些对判断和寻找晕核态有现实的指导意义. 关键词： 单粒子势模型 价核子 密度分布 中子晕核态 质子晕核态     

用电子散射研究丰质子核的质子晕结构

理论和实验结果都表明¹⁷F的第一激发态有质子晕存在.用相对论平均场理论和Eikonal近似研究了质子晕核¹⁷F的第一激发态的电子弹性散射过程. 计算了¹⁷F的第一激发态的电荷形状因子,并与¹⁶O和¹⁹F的结果进行了对比和讨论.结果显示质子晕的存在会使中等转移动量的电荷形状因子产生明显的变化,并且使低转移动量的电荷形状因子趋于降低.这说明电子散射对质子晕的存在是非常敏感的,表明可以用电子散射对奇特核的质子晕结构进行更精细的研究.     

Experimental studies of the nuclear spatial structure of neutron-rich He and Li isotopes

Results of several experiments aimed at exploring the nuclear spatial structure of neutron-rich He and Li isotopes are presented and briefly discussed. The study of the density distributions in these nuclei by small-angle proton elastic scattering at intermediate energy is considered in more detail. The performed investigations allow one to obtain information on the total matter distributions, radii of the matter, neutron and proton distributions, effective and internal core sizes, halo sizes, and spatial correlations of the halo nucleons in the studied nuclei. The text was submitted by the authors in English.     

Proton halos in exotic light nuclei

The current study on proton halos in exotic light nuclei is reviewed and discussed. We place emphasis on the newly discovered proton halo in ²³Al. A measurement of the reaction cross section of N=10 isotones and Z=13 isotopes is performed at Lanzhou in China. An abnormal increase in the reaction cross section is observed for ²³Al. This abnormal increase, combined with other data, strongly suggests that there is a proton halo in ²³Al. The possible cause for a proton halo in ²³Al is analyzed, and it is found that deformation can be important for it. Other candidates for proton halos are predicted.