Straw tube detectors operating as drift detectors are commonly used in nuclear and particle physics experiments. The straw tubes are arranged in layers and placed in areas both with and without magnetic field. In order to resolve the 3D coordinates of a track, the straws are placed in multiple overlapping layers at varying angles of inclination. By measuring the drift time and then converting it to the drift distance, a position resolution per straw can be achieved. Knowing the geometry of the detector, the position of hit straws and the drift distances, it is possible to determine the tracks of the moving particles. In the paper we present the algorithm for the 3D track reconstruction in areas without magnetic field by using vertical and skewed straws. The algorithm has been prepared for the Forward Tracker in the PANDA experiment.

Straw tube detectors operating as drift detectors are commonly used in nuclear and particle physics experiments. The straw tubes are arranged in layers and placed in areas both with and without magnetic field. In order to resolve the 3D coordinates of a track, the straws are placed in multiple overlapping layers at varying angles of inclination. By measuring the drift time and then converting it to the drift distance, a position resolution per straw can be achieved. Knowing the geometry of the detector, the position of hit straws and the drift distances, it is possible to determine the tracks of the moving particles. In the paper we present the algorithm for the 3D track reconstruction in areas without magnetic field by using vertical and skewed straws. The algorithm has been prepared for the Forward Tracker in the PANDA experiment.