Modelling of Beam Dynamics for the New Muon g-2 Experiment at FNAL

Measurements of the anomalous magnetic moment (g-2) of the muon have indicated a small difference from the value predicted by the Standard Model of particle physics: any difference would indicate the existence of new physics. However, the precision of existing measurements is not sufficient to confirm a discrepancy between theory and measurement with any certainty. A new experiment, presently under construction at Fermilab, aims to improve the measurement precision of the muon g-2 by at least a factor of four over previous measurements. This will establish with confidence whether or not there is a significant difference between the measured and theoretical values.
The anomalous magnetic moment of the muon is measured by observing the spin precession of a bunch of muons as they move through a uniform magnetic field in a storage ring. The precision of the measurement depends critically on a detailed understanding of the properties of the particles as they are injected into the storage ring, including (for example) effects such as correlations between spin and momentum. The goal of this project is to construct a computer model including all relevant details of the accelerator systems, from the production target for pions (which decay into muons), through various transport lines to the storage ring. Using this model, it will be possible to identify the potential impact of numerous machine properties on the measured value of the muon g-2, allowing reduction of systematic errors and yielding a value for g-2 with sufficient precision to determine the existence of any new physics.