Central Exclusive Production and Forward Physics at the LHC

粒子物理学的目的是对基本粒子和影响它们的力有一个完整的了解。50多年来，粒子物理学家一直在相互撞击粒子，并观察其后果。这使得一种非常成功的模式，即标准模式得以形成。2007年，大型强子对撞机将启动。大型强子对撞机将在一次碰撞实验中达到有史以来最高的能量，并将探索一个质量范围，理论家预测，在这个质量范围内，标准模型将被打破，新的粒子将被发现。大型强子对撞机的工作原理是质子的碰撞，质子本质上是称为夸克和胶子的基本粒子的袋子。在碰撞中，每个质子中的一个组成粒子相互作用，其余的质子在粒子簇射中破裂。提取有趣的物理学并不容易，正因为如此，大型强子对撞机被称为一台发现机器--因为精确的测量将是极其困难的。在我的研究中，我专注于一种情况，在这种情况下，质子不会分裂，相互作用产生的所有能量都会产生一个中心物体。这样做的好处是，环境更清洁，质子本身也可以被检测到。随后对质子能量和动量的测量使中心物体得以极其精确地测量。这就把大型强子对撞机变成了一台精密机器。此外，在一些理论预测中，发现一些新物理学的唯一方法就是使用这种方法。为了测量质子，我们需要距离相互作用点420米的探测器。安装这些探测器的提议是一个新想法，需要进行大量研究才能实现。我将继续评估这一过程的物理潜力，并产生新的技术和定义，以克服这个项目所预见的一些实验挑战。例如，在大型强子对撞机上，每秒有大量的碰撞，不可能将它们全部存储起来。因此，我们必须选择我们认为有趣的事件--这称为触发。有两个级别的触发和来自质子探测器的信息将只在第二个级别可用；因此，事件必须通过级别1。遗憾的是，目前许多这样的事件不会通过，需要新的级别1触发定义。同样，如果选择了事件，我们必须有一种在分析级别识别它们的方法。还会有其他事件模仿我们想要的事件，目前将它们分开的方法是不够的。最后，要做到这一切，我们必须有一个计算机模拟，充分模拟我们想要看到的东西。我已经制作了一个这样的模型，但为了完整地表示物理学，还有很多东西需要添加到其中。总而言之，人们对大型强子对撞机能够接触到新的物理学抱有很大的期望。这项研究将扩大我们探测这种物理的可能性，这当然是这个领域的主要目标。

The aim of particle physics is to obtain a complete understanding of fundamental particles and the forces that affect them. For more than 50 years, particle physicists have been smashing particles into each other and observing the consequences. This has allowed a very successful model, known as the Standard Model, to be formulated. In 2007, the Large Hadron Collider is due to turn on. The LHC will reach the highest ever energies at a colliding experiment and will probe a mass range at which, theorists predict, the Standard Model will break down and new particles will be discovered. The LHC works by colliding protons which are essentially bags of fundamental particles known as quarks and gluons. At the collision, one constituent particle from each proton interacts and the rest of the proton breaks up in a shower of particles. Extracting the interesting physics is not easy and because of this the LHC is known as a discovery machine - as precision measurements will be extremely difficult. In my research, I focus on a scenario where the protons do not break up and all the energy from the interaction goes into producing a central object. This has the advantage that the environment is cleaner and the protons themselves can be detected. The subsequent measurement of the proton's energy and momentum allows the central object to be measured extremely accurately. This turns the LHC into a precision machine. Furthermore, in some theoretical predictions, the only way to discover some of the new physics is to use this method. In order to measure the protons, we require detectors 420m away from the interaction point. The proposal to install these detectors is a new idea and a lot of research is required to make it happen. I will continue to evaluate the physics potential of this process and produce new techniques and definitions in order to overcome some of the forseen experimental challenges of this project. For example, at the LHC there are a huge number of collisions each second and it is not possible to store them all. Consequently, we have to select events that we think are interesting - this is known as triggering. There 2 levels of triggers and information from the proton detectors would only be available at the second level; therefore the events must pass level 1. Unfortunately, at present, many of these events will not pass and a new level 1 trigger definition is required. Similarly, if the events are selected, we must have a way of identifying them at an analysis level. There will be other events that mimic the ones that we want and the current method of separating them is not sufficent. Finally, to do all of this we must have a computer simulation that adequately models what we want to see. I have produced such a model, but there is a great deal to be added to it in order to have a complete represention of the physics. In summary, there is a great expectation that new physics is accessible at the LHC. This research will extend the possibility that we will detect this physics, which is of course the primary aim of this field.