中国极化电子—离子对撞机

电磁相互作用把质子与电子束缚起来,形成氢原子。人类对于电磁相互作用的深刻认识发展出智能手机和信息技术,给日常生活带来了极大的便利。相比之下,夸克和胶子如何被强相互作用束缚从而形成质子与中子,人类还缺乏充分的认识。因此,全球的中高能核物理学家提出了建设未来高精度极化电子—离子对撞机以对其进行更深入的研究。文章主要介绍中国极化电子—离子对撞机实验上的物理问题,以及量子色动力学格点计算在这些物理研究中的重要作用。     

Collider physics at HERA

From 1992 to 2007, HERA, the first electron-proton collider, operated at cms energies of about 320 GeV and allowed the investigation of deep-inelastic and photoproduction processes at the highest energy scales accessed thus far. This review is an introduction to, and a summary of, the main results obtained at HERA during its operation.     

Collider signals of unparticle physics

Phenomenology of the notion of an unparticle U, recently perceived by Georgi, to describe a scale invariant sector with a nontrivial infrared fixed point at a higher energy scale is explored in details. Behaving like a collection of d(U) (the scale dimension of the unparticle operator O(U)) invisible massless particles, this unparticle can be unveiled by measurements of various energy distributions for the processes Z-->f f U and e- e+-->gammaU at e- e+ colliders, as well as monojet production at hadron colliders. We also study the propagator effects of the unparticle through the Drell-Yan tree-level process and the one-loop muon anomaly.     

电子-离子对撞机上开展核子及其激发态研究的建议

核子及其激发态性质研究一直是中高能核物理的一个重要研究领域。然而,到目前为止,对核子及其激发态内部结构的了解还处在初级阶段。首先介绍了核子及其激发态研究现状,指出了三夸克模型在描述核子特别是核子激发态内部结构方面存在很大的缺陷。为解决传统三夸克模型的不足,有一种新的观点认为虽然独立的五夸克态不存在,但是核子及其共振态中存在可观的五夸克激发。这种五夸克图像提供了一个描述核子内部结构的新见解,给出了与经典三夸克图像相当不同的核子激发态谱预言,还有待实验检验。目前国内外正在论证的电子–离子对撞机(EIC)将是研究核子结构下一代最重要的加速器装置,被视为"超级电子显微镜"。由于EIC有较高的能量和亮度,特别是低本底等优势,可以开展核子及其激发态性质的研究以及新强子态研究。     

Electroweak and CP violation physics at a Linear Collider Z-factory

A future linear collider such as TESLA may be able to run on the Z⁰ resonance with very high luminosity and polarised electron and positron beams. The possibilities of measuring electroweak quantities with high precision are investigated. Huge improvements with respect to the present precision can be expected, especially for the asymmetries A_LR and where beam polarisation can be exploited. The very large sample of events also allows studies of various CP-violating b decays. The precision achievable on the CKM unitarity triangle angles is comparable to experiments at b factories and future hadron colliders.     

Dijet physics with CMS detector at the Large Hadron Collider

The results from various dijet distributions in proton?Cproton collisions at a centre-of-mass energy of 7 TeV, with 2010 and 2011 data from the CMS experiment, are presented. The measurements of the dijet mass spectra, centrality ratio, azimuthal decorrelation and angular distribution are shown. Sensitivity of the phenomenological parameters used to model different event generators is also investigated. Prospects for observing evidence for new physics in these distributions are presented.     

Relativistic Heavy-Ion Collider (RHIC) physics overview

The results from data taken during the last several years at the Relativistic Heavy-Ion Collider (RHIC) will be reviewed in the paper. Several selected topics that further our understanding of constituent quark scaling, jet quenching and color screening effect of heavy quarkonia in the hot dense medium will be presented. Detector upgrades will further probe the properties of Quark Gluon Plasma. Future measurements with upgraded detectors will be presented. The discovery perspectives from future measurements will also be discussed.     

Nuclear physics with hyperfine methods

In this talk the discussion of nuclear physics studied by hyperfine methods is limited to a few topics of high actuality:

Nuclear physics with synchrotron radiation

The characteristics of synchrotron radiation originating from a very high energy electron-positron storage ring are presented. Emphasis is put on the high energy part of the spectrum which is relevant to nuclear physics research. The physics potential of such intense photon beams is reviewed with discussions of photonuclear reactions and of neutron-induced reactions with photoproduced neutrons.     

Search for new physics at Large Hadron Collider

We review the search for new physics to be done at Large Hadron Collider,—search for Higgs boson, supersymmetry, and exotic.     

Collider physics at high energies and low luminosities

While very high acceleration gradients are expected in novel accelerating schemes such as those discussed by IZEST, generating high luminosities will be extremely challenging and will likely require a separate technology revolution. It is important to determine if a low-luminosity but high energy collider would have serious interest from a particle physics perspective. We consider a process involving physics beyond the Standard Model that would be detectable at high energies without requiring the types of luminosities normally quoted for future colliders, “classicalization”. In this example, scattering cross sections grow with a power of the center-of-mass energy, thereby reducing the luminosity requirement at high energies. Another process discussed is deep-inelastic-scattering of electrons on protons, where a precision measurement of the energy dependence of the scattering cross section could yield information about physics processes at much higher scales.     

Working group report: Collider and B physics

The activities of the working group including some of the seminars are summarized. The written reports received are included.     

Working group report: Collider and flavour physics

The activities of the working group took place under two broad subgroups: Collider Physics subgroup and Flavour Physics subgroup. Reports on some of the projects undertaken are included. Also, some of the leading discussions organized by the working group are summarized.      

邮票上的物理学史(57)--原子核物理学

前面说过的放射性、同位素、中子、裂变、聚变、反应堆都属于原子核物理学.本节讨论原子核物理学更进一步的内容.     

Reconstruction of physics objects at the Circular Electron Positron Collider with Arbor

After the Higgs discovery, precise measurements of the Higgs properties and the electroweak observables become vital for the experimental particle physics. A powerful Higgs/Z factory, the Circular Electron Positron Collider (CEPC) is proposed. The Particle Flow oriented detector design is proposed to the CEPC and a Particle Flow algorithm, Arbor is optimized accordingly. We summarize the physics object reconstruction performance of the Particle Flow oriented detector design with Arbor algorithm and conclude that this combination fulfills the physics requirement of CEPC.     

Nuclear physics with RI Beam Factory

Research activities of nuclear physics at Radioactive Isotope Beam Factory over 10 years are reviewed and future directions are also discussed. Conceptual ideas in designing the facility as well as experimental devices are introduced. Special emphasis is given to highlighted results obtained at RIBF.     

激光核物理

在最近十年,激光技术有了长足的进展,激光的强度超过了1022W/cm2, 激光的电场达到~4×1012V/cm.当这种高强度的激光照射在靶上时,可以产生许多由激光产生的核反应现象.在这篇文章中,作者回顾了这一领域的研究进展,并对在不远的未来激光产生电子、质子、中子、X射线和正电子发展的潜力进行了一些讨论.