PDLC制备过程中聚合物和液晶的选择

介绍了使用聚合引发相分离(包括热固化、紫外光固化和电子束固化)制备聚合物分散型液晶(PDLC:PolymerDispersedLiquidCrystal)的工艺和原材料,对不同聚合物与液晶的匹配进行了简单分析和总结,并整体评价了这些方法,指出了在实际应用过程中容易遇到的各种问题,对聚合物分散型液晶的制备工艺有一定借鉴作用。

Strangeness Production Process pp → nK^＋∑^＋ within Resonance Model

We explore production mechanism and final state interaction in the pp → nK^＋∑^＋ channel based on the inconsistent experimental data published respectively by COSY-11 and COSY-ANKE. The scattering parameter a 〉 0 for n∑^＋ interaction is favoured by large near-threshold cross section within a nonrelativistic parametrization investigation, rand a strong n∑^＋ interaction comparable to pp interaction is also indicated. Based on this analysis we calculate the contribution from resonance △^＊ （1920） through π^＋ exchange within resonance model, and the numerical result suggests a rather small near-threshold total cross section, which is consistent with the COSYANKE data. With an additional sub-threshold resonance △^＊（1620）, the model gives a much better description to the rather large near-threshold total cross section published by COSY-11.

中国极化电子离子对撞机计划

轻子散射实验是探索核子与原子核结构的理想工具。中国电子离子对撞机(Electron Ion Collider in China,EicC)建议书设想在已开建的强流重离子加速器装置(High Intensity heavy ion Accelerator Facility,HIAF)的基础上,升级质子束流为20 GeV的极化束流,并建造2.8~5 GeV极化电子束流,从而实现质心系能量为15~20 GeV的双极化电子-离子对撞。EicC设计的亮度为(2~4)×10^33cm^-2·s^-1,质子束流极化率达到70%,电子束流极化率达到80%。该装置除了能提供极化轻离子束流(例如:氦-3)外,也可产生非极化重离子束流(碳-12~铀-238)。EicC将聚焦核子海夸克部分子结构、原子核物质结构与性质、奇特强子态三个方面的物理研究。高亮度、高精度的对撞机有助于精确地测量核子结构函数并对核子进行三维成像,揭示强相互作用的动力学规律;原子核部分子分布包括核子短程关联以及原子核介质效应同样是该提案的重要科学目标;EicC能区接近重味夸克产生阈值,在研究重味强子谱方面拥有低背景的独特优势,有助于发现研究新的奇特强子态。质子质量起源问题也可以通过重味矢量介子的产生来研究。为了完成上述物理目标,我们将利用最先进的探测器技术建造接近全立体角覆盖的EicC对撞机谱仪。在准备EicC白皮书的过程中,我们得到世界各国专家的支持。EicC的物理与已有的实验和美国即将建设的EIC中的物理项目相互补充。EicC的建成及运行有望引领前沿的中高能核物理研究,使我国在加速器和探测器先进技术等领域实现跨越式发展,为我国核物理与强子物理以及相关科学领域提供大型综合实验平台与人才培养基地。

中国极化电子离子对撞机(EicC)物理及探测器设计研究

核子(质子和中子的总称)大约占宇宙中可见物质总质量的99%.作为构成宇宙可见物质中的最主要成分,核子也是研究强相互作用,尤其是禁闭区非微扰QCD的重要实验室.电子离子对撞机(Electron Ion Collider, EIC),被称作当代卢瑟福散射实验,是人类认识物质世界深层次结构,特别是核子与原子核结构的理想工具.中国极化电子离子对撞机项目设想在已开建的HIAF高能离子束的基础上升级建造中国电子-离子对撞机(EIC in China,EicC),为我国核物理与粒子物理以及相关科学领域提供大型综合实验平台.本文综述了EicC在核子内不同味道海夸克的一维自旋味道结构、横动量依赖部分子分布函数、广义部分子分布函数测量的理论和模拟研究,展示了EicC在以上测量中可达到的预期精度,以及与现有测量精度的对比.另外,本文也综述了EicC在质子质量起源、重味强子谱、核介质效应及π介子的内部结构等重要物理问题中的潜在贡献,以及EicC探测器概念设计.EicC装置将有力地促进人们对核子自旋和质量的起源、夸克胶子禁闭机制等基本问题的理解.

加速器驱动的次临界系统生产^(233)U的可行性研究

加速器驱动的次临界系统(Accelerator Driven Sub-critical System,ADS)是加速器技术和核反应堆技术的结合,其主要目的是应对当今快速增长的放射性核废料处理需求.本文初步探讨了在ADS系统中利用232Th生产可裂变核233U的可能性,估计了所需加速器的性能及其生产233U的产率和效率.我们建议用Be做中子慢化剂和增殖剂,将反应堆的中子能量大部分控制在1keV–1MeV,从而最大限度地降低232U的含量.也可进一步利用重水做慢化剂高233U的纯度.所生产的233U既可经分离取后在热堆中燃烧,也可直接用于钍基熔盐堆的初始装料,发挥233U优异的热中子性能.我们的结果表明,在技术上和经济上利用ADS生产233U很可能是可行的.我们的结果还表明,如果这一ADS系统主要目的是生产233U,所选择的次临界堆的最佳是快中子堆,而不是慢中子堆或快慢结合堆.最后我们建议对钍基核反应堆、233U的取分离工和辐射防护等方面的课开展进一步深入研究.

利用光前量子化方法计算电子的广义横向动量分布函数

强子和轻子是目前实验所能观测到的最小微观结构,但根据量子色动力学(QCD),强子内还存在着部分子结构。在理论计算中,从Wigner函数出发可以得到多种分布函数,如横向动量分布函数(TMD)、广义部分子分布函数(GPD)以及广义横向动量分布函数(GTMD)。其中GTMD包含粒子内部部分子的三维动量和位置信息,从GTMD出发通过对横向动量积分和取横向转移动量为零分别得到GPD和TMD。本工作通过引入电子的光前波函数计算出物理电子的GTMD,并以此为出发点得到物理电子的TMD和GPD。一方面通过与微扰论的TMD和GPD的结果对比可以证明我们的计算结果是合理的,同时讨论了GPD中P波和S波的贡献。另一方面给出物理电子的内部部分子分布随横向转移动量、部分子横向动量以及纵向动量分数的变化关系。

Nucleon resonances in πN→η'N and J/ψ→pη'

We are aiming to study the J/ψ →pqη′ decay in an isobar model and the effective Lagrangian approach on the basis of the coupling constants extracted from the πN→η′ reaction. After a careful exploration of the contributions of the S11（1535）, P11（1710）, P13（1900）, S11（2090） and Pl,（2100） resonances, we conclude that either a subthreshold resonance or a broad P-wave state in the near threshold range seems to be indispensable to describe the present data of the πN→η′.Furthermore, at least one broad resonance above rl＇N threshold is preferred. With this detailed analysis, we give the invariant mass spectrum and Dalitz plot of the J/ψ →pqη′decay for the purpose of assisting the future detailed partial wave analysis. It is found that the J/ψ →pqη′ data are useful for disentangling the above or below threshold resonant contribution, though it still further needs the differential cross section data of πN→η′ to realize some of the resonant and non-resonant contribution.

Disentangling the nature of resonances in coupled-channel models

We present severM possible hadronic states found in coupled-channel models within the on-shell approx- imation. The interaction potential is constructed as a sum of the tree-level Feynman diagrams calculated with the effective Lagrangians. Based on the recent empirical data, we illustrate the possible existence of severM baryonic and mesonic states with definite quantum numbers in the model. We give their properties for the purpose of further study and discuss the potential of finding them in future experiments.

N*(1535) contribution in pp→ppη′ and pn→dφ

In an effective Lagrangian model we find that the N＊（1535） resonance contribution might be important to the interpretation of the present data of the pp →ppη＇ and pn →dφ reactions. The strong coupling strength of N＊ （1535） to η＇ and φ are indicated, and the possible implication to the intrinsic component of N＊（1535） is explored. These results may provide hints to the real origin of the OZI rule violation. It is stressed that further measurements could be performed at China. the Cooling Storage Ring （CSR） at Lanzhou of

The Role of α1(1260) in π^-p→α1^-(1260)p and π^-p → π^-ρ^0p Reactions Near Threshold

We report on a theoretical study of the π^-ρ→α1(1260)p and π^-ρ→π^-ρ~0p reactions near threshold within an effective Lagrangian approach.The production process is described by t-channel ρ~0 meson exchange.For the π^-ρ→π^- ρ~0p reaction,the final π^-ρ~0 results from the decay of the α1(1260) resonance,which is assumed as a dynamically generated state from the K* K and ρπ coupled channel interactions.We calculate the total cross section of the π^-ρ→α1(1260)p reaction.It is shown that,with the coupling constant of the α1(1260) to ρπ channel obtained from the chiral unitary theory and a cut off parameter Δρ~1.5 GeV in the form factors,the experimental measurement can be reproduced.Furthermore,the total and differential cross sections of π~p→α1(1260)p→π~ρ~0p reaction are evaluated,and it is expected that our model calculations can be tested by future experiments.These reactions are important for the study of the α1(1260) resonance and would provide further constraints on the properties of the α1(1260) state.

Identifying hidden charm pentaquark signal from non-resonant background in electron–proton scattering

In this study,we analyze the electroproduction of the LHCb pentaquark states with the assumption that they are resonant states.Our main concern is to investigate the final state distribution in the phase space to extract a feeble pentaquark signal from a large non-resonant background.The results indicate that the signal to background ratio will increase significantly with a proper kinematic cut,which will be beneficial for future experimental analysis.

Production of hidden-charm and hidden-bottom pentaquark states in electron-proton collisions

Electro-production of several pentaquark states is investigated in this study.The eSTARlight package is adapted to study the electro-production of J/ψand γ(1S)via pentaquark P_(c)and P_(b)resonance channels in ep→eJ/ψp and ep→eγ(1S)p scattering processes at the proposed electron-ion colliders(EICs).The results obtained in this study are compared to those of non-resonance t-channels,which are described in the pomeron exchange model developed in our studies.Some pseudo-rapidity and rapidity distributions of J/ψand γ(1S)are presented for the proposed EICs,including EicC and EIC-US.It is found that EicC is a good platform to identify P_(b) states in the future.