Institute for Particle Physics Phenomenology

到目前为止，电磁、弱和强相互作用的标准模型(SM)规范理论已经经受住了LEP、HERA和Tevatron所能构成的所有挑战，并且证实了SM的有效性-电磁和弱相互作用的统一被证明和测试到了百万分之一。强大的相互作用效应已被测试到百分之一的水平。气味现象在塑造SM的整体结构中做出了与规范原理同样多的贡献，正是气味的存在(在轻子和夸克部门中)赋予了SM的家族和世代结构。在夸克区，对气味现象的SM描述和在规范区的SM预测一样成功，而混合和CP破坏的CKM图现在在几个百分点的水平上得到了验证。然而，中微子振荡的观测，以及随后中微子具有质量的证据要求扩大SM和中微子的质量，这可能成为大统一尺度上的一个物理窗口。2008年，随着大型强子对撞机(LHC)开始以比以往更高的能量加速和碰撞质子，粒子物理学即将迎来新的重大实验发现。大型强子对撞机将开辟TeV尺度物理学的新领域，已知粒子和相互作用的理论描述被打破，新物理学的诞生势在必行。预计会有突破性的发现。特别是，与理解所有基本粒子的质量起源有关的负责电弱对称破缺的机制将在TeV尺度上表现出来。它可能会产生一个或多个新的基本标量粒子，希格斯玻色子，产生一种新的强相互作用或其他可能意想不到的现象。此外，预计TeV尺度上的实验将对新的物理贡献的影响敏感，这些新的物理贡献稳定了弱尺度和普朗克尺度之间的巨大等级。SM之外的物理学的主要候选者是超对称性，它假设费米子和玻色子之间存在对称性，并将空间--时间嵌入到“超空间”中，即额外的空间维度，空间可以非常小，甚至可以无限大。大型强子对撞机的高能范围将允许探索TeV尺度的物理。然而，大型强子对撞机实验比以往的任何粒子物理实验都要复杂得多。在TeV尺度上识别物理学的本质将需要实验者和理论家之间激烈的合作努力。在理论方面，需要对SM过程进行高精度的计算，以区分可能的新物理信号和SM背景。新物理的可能线索需要与SM之外的不同物理模型进行比较，以便理清TeV尺度物理的基本结构。IPPP已经与英国和国际实验小组建立了密切的联系，并处于完美的地位，可以帮助英国最大限度地帮助理解大型强子对撞机数据。一旦确定了新物理的能量规模，将在规划和设计下一代粒子物理实验方面做出强有力的努力。IPPP将继续发挥其在评估物理潜力和未来加速器设计方面的作用，例如，通过加入国际直线对撞机全球设计工作和中微子工厂国际设计研究。下一个十年有望成为我们理解微观世界的关键。IPPP将解决以下基本问题：电弱对称破缺，时空结构，味物理和CP破坏，中微子和轻子味破坏，以及粒子物理如何与天体物理和宇宙学联系起来。

The Standard Model (SM) gauge theory of electromagnetic, weak and strong interactions has so far withstood all the challenges that LEP, HERA and the TEVATRON have been able to pose and the validity of the SM is confirmed --- with the unification of electromagnetism and weak interactions proved and tested to one part per mille. Strong interaction effects have been tested to the per cent level. Flavour phenomena have contributed as much as the gauge principle in shaping the overall structure of the SM and it is the existence of flavours (in both the lepton and quark sectors) that gives the SM its family and generation structure. In the quark sector the SM description of flavour phenomena is as successful as the SM predictions in the gauge sector and the CKM picture of mixing and CP violation is now verified at the few per cent level. However, the observation of neutrino oscillations, and the consequent evidence that neutrinos have mass calls for an extension of the SM and neutrino masses may become a window on physics at the grand unification scale. In 2008, particle physics stands poised at the verge of new and major experimental discoveries as the Large Hadron Collider (LHC) starts to accelerate and collide protons at much higher energies than ever before. The LHC will open up the new territory of TeV scale physics, where the theoretical description of the known particles and interactions breaks down, necessitating the onset of new physics. Ground-breaking discoveries are expected. In particular, the mechanism responsible for electroweak symmetry breaking that is ultimately related to the understanding of the origin of the masses of all elementary particles will manifest itself at the TeV scale. It may give rise to one or more new elementary scalar particles, the Higgs bosons, to a new kind of strong interaction or to other possibly unexpected phenomena. Furthermore, it is expected that experiments at the TeV scale will be sensitive to effects of new physics contributions that stabilise the huge hierarchy between the weak scale and the Planck scale. Prime candidates for physics beyond the SM are supersymmetry, which postulates a symmetry between fermions and bosons and embeds space--time into a ``superspace'', or additional dimensions of space, which may either be very small or even infinitely large. The high energy reach of the LHC will allow the exploration of TeV scale physics. However, the LHC experiments are significantly more complex than any previous particle physics experiment. Identifying the nature of physics at the TeV scale will require intense collaborative efforts between experimentalists and theorists. On the theoretical side, high-precision calculations of SM processes are needed to distinguish possible signals of new physics from SM backgrounds. Possible hints of new physics need to be compared with different models of physics beyond the SM in order to disentangle the underlying structure of TeV-scale physics. The IPPP has already established close connections with the UK and international experimental groups and is perfectly placed to help maximise the UK contribution to understanding the LHC data. Once the energy scale of new physics is identified, there will be a strong effort in planning and designing the next generation of particle physics experiments. The IPPP will continue its role in assessing the physics potential and the design of future accelerators, for example, through membership of the Global Design Effort for the International Linear Collider, and the International Design Study for the Neutrino Factory. The next decade promises to be pivotal in our understanding of the microscopic world. The IPPP will address fundamental questions about electroweak symmetry breaking, the structure of space-time, flavour physics and CP violation, neutrinos and lepton-flavour violation, and how particle physics connects with astrophysics and cosmology.