  We discuss the reconstruction of low-energy nuclear reaction kinematics from
charged-particle tracks in solenoidal spectrometers working in Active Target
Time Projection Chamber mode. In this operation mode, reaction products are
tracked within the active gas medium of the Active Target with a three
dimensional space point cloud. We have inferred the reaction kinematics from
the point cloud using an algorithm based on a linear quadratic estimator
(Kalman filter). The performance of this algorithm has been evaluated using
experimental data from nuclear reactions measured with the Active Target Time
Projection Chamber (AT-TPC) detector.

Instrumentation and Detectors;Nuclear Experiment