A simplified model of the task. You throw 10,000 springs of various sizes (particle trajectories) into a box and record the intersection points (hits) with a se

A simplified model of the task. You throw 10,000 springs of various sizes (particle trajectories) into a box and record the intersection points (hits) with a set of (spring-penetrable) nested cylinders (detectors) in that box. You will get on average about 10 intersection points per spring. Now given those 100,000 intersection points, reconstruct the size, position, and orientation of the 10,000 springs. Lets add the facts that all the springs are aligned along one axis and that the cylinders are nested around that axis to be geometrically closer to reality. The hardness is due to possible ambiguities of what collection of springs caused the observed intersection points, imperfections in the helical shape of the springs and the cylindrical shape of the detectors, limited resolution of the measured intersection points, and missed (detector efficiency »only« 99 %) or added (detector noise) intersection points.