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CEDAR: the physics problem

Particle physics experiments at high-energy accelerators provide a wealth of data on the interactions between elementary particles. These data represent a triumph for the Standard Model of particle physics, having verified many of its predictions to an impressive degree of precision.

However, several aspects of high-energy collisions are poorly understood or difficult to predict, often due to technical difficulties in the required calculations. These effects are described by phenomenological models that have free parameters which must be tuned to agree with experimental data. Monte Carlo programs are used to generate collision events according to a particular model, and the properties of these events can be compared with those measured in real experiments.

In order to make the best possible use of future colliders such as the Large Hadron Collider and the Future Linear Collider, while still keeping the lessons learned in current and past experiments, we need to test these models using as much information as we can extract from existing data. This is a non-trivial matter since many measurements of different complex observables, made with different colliding beams, are involved. These observables depend on the model parameters in various different ways and it is easy to tune a model to one set of data only to find that the agreement with other data has been lost.

Last updated: Thu Jan 18 10:54:33 2007