Central Exclusive Production and Forward Physics at the LHC

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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.