Improving the Tracking of Subatomic Particles Using the Unscented Kalman Filter With Measurement Redundancy in High Energy Physics Experiments.

In this paper, the unscented Kalman filter (UKF) is applied to a particle tracking problem in the high energy physics (HEP) experiments, where the determination of position and momentum associated to a particle with a high level of the desired accuracy, in the presence of multiple scattering and ionization energy loss, is crucial. The main issue that naturally arises due to such particle and detection dynamics is relative (marginal) observability which causes the existing track reconstruction algorithm, the Extended Kalman filter (EKF), to underperform or even diverge which has been elaborated through a comparison with the UKF. We present this challenging problem and investigate the issue of relative observability in terms of its relationship with measurement redundancy in order to improve the performance of the UKF. We also present an interesting issue where no duplicate measurements are available due to the measurement setup used at the HEP system under consideration and how in that particular scenario redundancy can be introduced.