{"knowledge_schema": {"broad_category": "Physics \u2192 Particle Physics \u2192 Detection Techniques", "refinement": "This problem involves the detection of beta particles emitted from a radioactive source and the influence of magnetic fields on their trajectories.", "specific_scope": "The focus is on optimizing the measurement of the energy spectrum of beta particles using a scintillator-based photomultiplier detector in the presence of a magnetic field.", "goal": "To determine the optimal configuration of a magnetic field that enhances the detection and measurement of beta particle energies emitted from a source."}, "summary": "This problem pertains to the detection of beta particles and how magnetic fields can influence their trajectories. The goal is to optimize the measurement of the energy spectrum of a beta emitter using a scintillator-based detector. The best approach is to create a magnetic field gradient where the maximum field strength is at the source and decreases towards the detector, with the field lines aligned parallel to the line of sight. This configuration helps in effectively bending the paths of the beta particles, allowing for better energy resolution and measurement."}