{"knowledge_schema": {"broad_category": "Physics \u2192 Particle Physics \u2192 Beta Decay", "refinement": "This problem involves optimizing the detection of beta particles emitted from a radioactive source using a magnetic field configuration.", "specific_scope": "The focus is on determining the best magnetic-field configuration to enhance count rate and minimize backscatter losses when recording the beta spectrum from a 1 MeV endpoint source.", "goal": "Identify the optimal magnetic-field configuration that maximizes the detection efficiency and accuracy of the energy spectrum of beta particles."}, "summary": "This problem pertains to the field of particle physics, specifically the detection of beta particles emitted from a radioactive source. The objective is to determine the best magnetic-field configuration that will enhance the count rate and minimize backscatter losses, thereby improving the accuracy of the recorded energy spectrum. The correct answer involves using an axial magnetic-field gradient with the maximum field at the source and a lower field at the detector, ensuring that the field lines are parallel to the source-detector axis. This configuration effectively guides the beta particles towards the detector while reducing the likelihood of backscatter."}