电荷-宇称（CP）对称性破坏和夸克一轻子味物理——写在CP破坏发现和夸克理论提出40周年之际

简要地介绍了与电荷-宇称(CP)对称性破坏和夸克一轻子味物理有关的一些重要进展．从1964年发现CP破坏和提出夸克理论至今，这个领域就一直成为粒子物理研究的前沿领域，已研究和发展了整整40年，取得了许多辉煌的成就．在这篇文章中，着重评述了目前仍然热门的几个主要的研究方向：直接CP破坏的理论研究和实验验证，CP破坏机制和新的CP破坏源，中微子物理和新的味物理，夸克味物理和有效量子场理论，标准模型中味物理参数的预言和超对称大统一理论．同时对我国有关研究组在这些前沿方向做出的重要贡献作了重点简述．可以看出，在CP破坏和味物理这个重要前沿领域，仍然存在着许多未解之谜，使得粒子物理在21世纪既面临着巨大的挑战，又有着不断发展的机遇．     

电荷-宇称(CP)对称性破坏和夸克-轻子味物理——写在CP破坏发现和夸克理论提出40周年之际

简要地介绍了与电荷-宇称（CP）对称性破坏和夸克-轻子味物理有关的一些重要进展.从1964年发现CP破坏和提出夸克理论至今,这个领域就一直成为粒子物理研究的前沿领域,已研究和发展了整整40年,取得了许多辉煌的成就.在这篇文章中,着重评述了目前仍然热门的几个主要的研究方向：直接CP 破坏的理论研究和实验验证,CP破坏机制和新的CP破坏源,中微子物理和新的味物理,夸克味物理和有效量子场理论,标准模型中味物理参数的预言和超对称大统一理论.同时对我国有关研究组在这些前沿方向做出的重要贡献作了重点简述.可以看出,在CP破坏和味物理这个重要前沿领域,仍然存在着许多未解之谜,使得粒子物理在21世纪既面临着巨大的挑战,又有着不断发展的机遇.     

ETC相互作用对NLC实验中顶夸克对产生过程CP破坏的贡献

在Topcolor辅助的多标度人工色(TOPMTC)模型框架下计算了扩充人工色(ETC)相互作用对顶夸克对产生过程中CP破坏参数δ的贡献(δ=σ[e–e→t(–)–t(–)]–σ[e–e→t(+)–t(+)]/σ(e–e→t–t)).计算结果表明,对于合理的参数取值,ETC相互作用可对参数δ产生较大的修正(8.65×10^－3≤δ≤1.09×10^－2).期望在将来的NLC实验中能观测到此修正效应.     

强CP问题的避风港——重夸克

我们指出了讨论强CP问题的某些文献的疏漏,强调正确解决真空取向问题的重要性,以及必须反重夸克考虑进来.在给出了真空取向的基本方程以后,我们指出:夸克质量m与该夸克的动力学凝聚C^d之积m C^d=0是使=0的充分必要条件.以前人们只讨论过u夸克质量m_u=0的可能性.我们提议某重夸克的C^d=0的可能性.     

在中微子振荡中的CP破坏

讨论了中微子味混合与中微子振荡的理论,定量地研究了在中微子振荡中的CP破坏效应.在一类超对称模型中,计算了真空中中微子振荡几率和 CP破坏效应.     

强CP破坏与TC轴子

本文首先讨论了强CP破坏.PQ机制及标准模型中的轴子.本文建立了TC轴子模型给出了它的质量,衰变寿命以及与其它粒子的耦合形式.最后讨论了天体物理和宇宙学对TC轴子性质的限制,提出了宇宙线中应存在轴子的物理态.     

超新星核中的夸克相变及夸克质量效应

分别基于组夸克质量模型和流夸克质量模型, 讨论了超新星核心区两味夸克物质到更稳定的三味夸克物质的相变过程. 结果表明, 两种质量模型下相变的特征时标都短于10^-8s, 且质量越小的流夸克质量模型的相变速率越快;组分夸克质量模型下所得到的超新星核区的s夸克丰度, 中微子丰度及中微子总能量(除温度)相比前人的结果有轻微的增加, 而流夸克质量模型下所得到的这些参量的增加更为明显, 采用流夸克质量模型更有利于超新星的中微子延迟爆发机理的成功. 关键词： 夸克相变 组分夸克质量 流夸克质量 超新星     

关于夸克质量问题

指出了研究夸克质量的重要性、 科学意义和夸克质量产生的机制。 用夸克传播子定义了夸克的质量, 进而讨论了夸克的有效质量。 最后指出了存在的问题和研究前景。 Importance, scientific significance of studying quark mass, and the production mechanisim of quark mass have been pointed out. The quark mass is defined by quark propagator and from this definition we calculate effective mass of quark. Finally we also point out some open problems and perspective of this research field.     

B工厂探测器和CP破坏

1 .什么是Ｂ工厂Ｂ工厂也称Ｂ介子工厂 ,是指像“工厂”一样生产巨量的Ｂ介子 (带ｂ夸克的介子 )的加速器和探测器装置的总称。其亮度达 10 3 3 ｃｍ-2 ｓ-1—10 3 4ｃｍ-2 ｓ-1,比常规加速器约高出 10 0倍。Ｂ工厂通常是指现在运行的 4台加速器和探测器 ,即ＣＥＳＲ ＣＬＥＯ3(美国 ,Ｃｏｒｎｅｌｌ) ,ＨＥＲＡ Ｈｅｒａ -Ｂ (德国 ,ＤＥＳＹ ) ,ＫＥＫＢ -Ｂｅｌｌｅ (日本 )以及ＰＥＰⅡ -ＢａＢａｒ(美国 )。2 .为什么要建造Ｂ工厂物理学认为 ,宇宙开始时 ,正反粒子的分布是对称的。但是现实世界是物质的 ,而不存在反物质世界。这种结局…     

About the Mixing and CP Violation in Neutrino System

Suppose that the geometrical explanation to the weak CP phase in quark sector is also valid for neutrinos, the mixing and CP violation in neutrino system are discussed. We find that a J_Cp larger than 3 × 10^-3 implies the large-mixing solution for solar neutrino problem. In the case of bi-maximal mixing, we predict relative large CP violation with J_Cp larger than 10^-3 in neutrino system, except the third mixing angle approaching to 0 or π/2 very closely.     

CP Violation in the Linear Sigma Model

Motivated by the possibility of the formation of CP-odd domains in heavy ion collisions, we investigate the effects of CP violation on the chiral transition within the linear sigma model with two flavors of quarks. We also study how the CP-odd system is affected by the presence of a strong magnetic field, that is presumably generated in a non-central heavy ion collision. We find that both ingredients play an important role, influencing drastically the nature of the phase transition and the critical temperature.     

超子的稀有衰变及CP不守恒

简述了近些年来超子稀有衰变的理论和实验研究进展及其待解决的问题。简单地讨论了兰州CSR上进行超子稀有衰变实验的可能性。A brief review is given on recent studies of hyperon rare decay both in theory and experiment. Some problems which exist in the field are presented. A possibility of study on the rare decay of Hyperon ∑^＋ at CSR is discussed.     

从流夸克质量到组分夸克质量的动力学过渡的研究

在彩虹近似下用Dyson Schwinger 方程研究了禁闭夸克的传播子, 得到了夸克动力学质量随动量变化的关系, 即得到了从流夸克质量到组分夸克质量的动力学过渡.     

Neutrino Oscillation and CP Violation in Low Energy Phenomenology of an SUSY Model

Neutrino oscillation and CP violation effects are discussed in an SUSY model proposed in Ref. [1]. The oscillation probabilities expected by this model in short baseline and long baseline neutrino oscillation experiments are calculated.     

Charged Higgs Boson Pair Production via Gluon-Gluon Collisions in MSSM with CP Violation

The CP-violating effects to the subprocess gg → H H- are studied in the mSUGRA scenario at the CERN large hadron collider, by taking into account the experimental bounds of electron and neutron electric dipole moments.The CP-violating effects in this process are related to the complex phases ofμ and Af in the mSUGRA scenario. In our calculation we consider smallCP phases ofμ and Af and neglect the effects of neutral Higgs boson mixing. In this case the CP effects to the process mainly come from the complex couplings of Higgs-squark-squark. We find a strong dependence of charged Higgs boson pair production rate on the complex couplings in the parameter space of minimal supersymmetric standard model``     

Charged Higgs Boson Pair Production via Gluon-Gluon Collisions in MSSM with CP Violation

The CP-violating effects to the subprocess gg→H⁺H^- are studied in the mSUGRA scenario at the CERN large hadron collider, by taking into account the experimental bounds of electron and neutron electric dipole moments. The CP-violating effects in this process are related to the complex phases of μ and A_f in the mSUGRA scenario. In our calculation we consider small CP phases of μ and A_f and neglect the effects of neutral Higgs boson mixing. In this case the CP effects to the process mainly come from the complex couplings of Higgs-squark-squark. We find a strong dependence of charged Higgs boson pair production rate on the complex couplings in the parameter space of minimal supersymmetric standard model.     

Dynamically Running Mass of Light Quark and QCD Vacuum Condensates

Based on Dyson-Schwinger equations (DSEs) in “rainbow“ approximation, the dynamically running mass of light quark and QCD vacuum condensate are investigated. The structure of non-local quark vacuum condensate, the values of local vacuum condensate of quarks and quark-gluon mixture, and dynamical transition of quark mass from current quark to constituent quark are illustrated. At the same time, according to the knowledge and experience learned from an extensive study of the solutions of DSEs, a parameterized form of confining quark propagator is suggested for a practical use. The new parameterized form of quark propagator is analytic everywhere in the finite complex p2-plane and has no Lehmann representation. The predictions for p2-dependence of effective quark masses, Mf(p2), defined by the self-energy functions Af(p2) and Bf(p2), both from the numerical solutions of DSEs and from its parameterized form, are shown dynamically. Our conclusion is that all numerical results are consistent with empirical values used in QCD sum rules and lattice QCD calculations. For a qualitative study, the parameterized form is a sufficiently good approximation to confining quark propagator.