A parametrized Kalman filter for fast track fitting at LHCb

We present an alternative implementation of the Kalman filter employed for track fitting within the LHCb experiment. It uses simple parametrizations for the extrapolation of particle trajectories in the field of the LHCb dipole magnet and for the effects of multiple scattering in the detector material. A speedup of more than a factor of four is achieved while maintaining the quality of the estimated track quantities. This Kalman filter implementation could be used in the purely software-based trigger of the LHCb upgrade. (C) 2021 The Authors. Published by Elsevier B.V.

Automated summary

The paper presents an alternative implementation of the Kalman filter used for track fitting in the LHCb experiment, achieving a speedup of more than four times while maintaining the quality of estimated track quantities. This implementation uses simple parametrizations for particle trajectory extrapolation and considers the effects of multiple scattering in detector material.