Ion trajectory analysis program (ITAP)

ITAP is a 2 1/2-dimensional FORTRAN code developed for the first-order design of charged-particle transport systems. The Ion Trajectory Analysis Program (ITAP) utilizes the paraxial-ray equation with no space charge to determine image size and divergence along the beam line. A discretized transfer-matrix technique is used to model particle transport through drift spaces, symmetrical electrostatic lenses, quadrupoles, wein filters, sector mass separators, deflection plates, and solenoids. Dispersion effects are also included for the prisms. ITAP contains an iterative design option which can determine the excitations, thicknesses, or gaps required in the model to produce either a desired size or divergence at the pseudo-image. Multiple elements may be designed in sequence permitting complete model optimization. Output consists of trajectory data as well as summary tables which describe the focal properties of each ion-optical element. Plots of the trajectories, divergences, and specific transverse planes are also produced. (orig.)