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The article describes a medium-energy, injector-free synchrotron, which employs a strong focusing lattice for ion-beam guiding and hence is capable of accelerating ions of all the species. The synchrotron acts injector-free due to the synchronization of bunch circulation with the acceleration, which is commonly caused due to the energizing of the switching power supply by the trigger signal.

Experimental calculations of a uniform collisonless charged-particle beam indicates its instability under the forces of electrostatic and internal pressure. Increase in mode number and magnitude of the forces enhances instability, which leads to an increase in parallel temperatures and widening of the density profile. These facts indicate limitations in focusing of the lens system.

Experimental studies using a 5-m-long periodic solenoid channel over a wide range of focussing conditions help verify the smooth-approximation theory for the effective radius of a space-charge dominated beam in an axisymmetric periodic focusing channel. Smooth-approximation theory results for an average beam radius -R over one period and the ratio R/R(max) in the beam envelope, taking into account the spherical aberration, agree with the experimental data. Spherical aberration effect is large only for focusing conditions with space-charge, sigma(0) < 60 degrees, and is negligible for sigma(0) > 600 degrees.

An analytical model has helped in obtaining equilibrium quantities of interest from high-intensity charged particle beams such as the emittance, beam envelope and the number of beam halo particles. The results are particularized to the case of initially homogeneous beams, with azimuthal symmetry, and are focused by a constant magnetic field while confined in a linear channel.

The analysis of boundary conditions imposed by the infinite cathode emissivity and infinitely strong magnetic field has helped in determining the shape of the current density near the margin of the space charge. The implications for treating experimental measurements, design of high current devices, and particle beam extraction are discussed.

A study addresses the issue of applying modeling tools developed by Jansen for probe forming instruments, to projection lithography beam configuration. It is based on the premise that the inaccuracy of the extended two-particle (ETP) model for projections systems is linked to multi-dimensional fit function use. The ETP model is modified to extend their application to projection systems. The focus is on the trajectory displacement effect, a relevant interaction phenomenon.