IMPROVEMENT OF HELIUM IONS BEAM FORMATION AND TRANSPORT SYSTEM

Works on improvement of a beam formation and transport system from an accelerating section output to the target complex on NSC KIPT helium ions linear accelerator with output energy of 4 MeV, used for carrying out of radiating researches are continued. Results of researches spent with electromagnetic quadrupole lenses, forming a triplet are presented. Experiments with injected (120 keV) and accelerated (4 MeV) helium ions beams by means of advanced beam formation and transport system to a target are continued. The proposal on decrease in thermal loading of a triplet is formulated.

ENGINEERING OF THE LOW-ENERGY BEAM TRANSPORT LINE IN THE Не⁺ IONS LINAC

The design of a low-energy beam transport line in the helium ions linear accelerator is proposed. For experiments with the low-energy helium ions the vacuum chamber in a transport line is in addition included for an irradiation of investigated materials. The mathematical modeling method investigates coordination variants of an injector beam output emittance with an accelerating structure acceptance with use of electromagnetic quadrupole lenses, electrostatic lenses and the focusing solenoid. It is shown that the optimal variant, ad hoc, is the focusing solenoid application. The calculated value of a current of the helium accelerated ions makes 4.5 mА.

PRECISION DOUBLET OF MAGNETIC QUADRUPOLE LENSES FOR ION BEAM FORMATION

The precision doublet of magnetic quadrupole lenses is presented. The doublet yoke and poles made from a single piece of soft magnetic iron. Doublet manufacturing technology provides of alignment of the geometric axes in the lenses with an accuracy of a few microns. The doublet geometry was chosen to obtain the maximum magnetic induction at the poles for a given radius of the lens aperture as a result of numerical simulation. An experimental study of the doublet properties was carried out using a setup for field reconstruction technique for magnetic quadrupole lenses. The relative position of the physical axes of the lenses (the geometrical location of points with zero magnetic induction) and the magnitudes of the parasitic multipole field components were determined.

Behaviorof Ion Beams For Triplet Quadrupole Lenses

This research includes a study to understand the behavior of charged particles beam through consideration of systems of quadrupole triplet reaching to the optimum design of beam transport through a system of triplet quadrupole triplet lenses. In this work, tracing the path of charged particles beam has been within the free field space and quadrupole electrostatic lens system which include the triplet quadrupolelens by using matrices to described particle trajectories throughout the system. Matrix representation deals with ion beam as bunched and representing phase ellipse for both horizontal and vertical planes. The present work investigated the effect of the main parameters of triplet quadruple such as length of quadrupole, the distance between the lenses, voltage applying on lenses,second field free region length. Matlab program built to study these parameters, the results indicated that good focusing properties for both horizontal and vertical plane.