Tracking with A Common Tracking Software

Abstract: In high energy physics (HEP) experiments, the reconstruction of charged particle trajectories is one of the most fundamental yet computationally expensive parts of event processing. At future hadron colliders such as the High-Luminosity Large Hadron Collider (HL-LHC), there can be up to ten thousand particles per event. This increases the track reconstruction time by a factor about 5 compared to the current tracking environment. Efficient and fast tracking software is necessary to maintain and improve the tracking performance. This can benefit from both fast tracking algorithms and modern computing architectures with many cores and accelerators. The Acts (A Common Tracking Software) project encapsulates the current ATLAS tracking software into an experiment-independent software designed for modern computing architectures. It provides a set of high-level track reconstruction tools agnostic to the details of the detector and magnetic field configuration. Particular emphasis is placed on thread-safety of the code in order to support concurrent event processing with context-dependent detector conditions, such as detector alignments or calibrations. Acts aims in addition to be a research and development platform for studying innovative tracking techniques and exploiting modern hardware architectures.