Double Focusing Zero Dispersion Magnetic Spectrometer

A double focusing zero dispersion magnetic spectrometer has been constructed having the following properties: The spectrometer consists of two magnets, each $\text{n≅0.25}$ , 110° deflection, 30-in. radius of curvature, bending the particles in the same sense. For the central momentum $p_0$ , the useful solid angle ${\Omega }_0$ is ∼0.0055 sr with a possibility of improvement to 0.01 sr. The momentum acceptance $\mathrm{\Delta p}$ is in excess of ±4% with a useful solid angle Ω of ∼0.0015 sr at the 4% points. For a point source and for the solid angles and momentum acceptances given, over 90% of the trajectories terminate within a circle of 2-in. diameter at the focal plane.