Ion propulsion systems with a small thrust can be used in space missions for highly accurate controllability while possessing low power and propellant consumption. At the University of Giessen, radio-frequency ion thrusters are miniaturized with thrusts in the order of micro-Newtons (μN-RIT). As the size of the thruster becomes smaller, the plasma properties can not be measured inside a closed plasma chamber. The simulations are needed to investigate plasma properties like temperature, density pro- file which would aid further opimization. The kinetic simulations of plasma inside the RIT-1.0 thruster using in-house developed PlasmaPIC code that incorporates Monte-Carlo collisions (MCC) and Direct Simulation Monte Carlo (DSMC) for neutral gas distribution. For the RIT-2.5 an one size bigger thruster we have developed Kinetic-Fluid Particle In Cell model.

At NSCL/MSU, I worked on the gas stopper project working on the principle of reverse cyclotron concept. The new system is based on slowing down the fast ions in a sector-focusing cyclotron magnet in a chamber filled with Helium buffer gas at low pressure (up to 150 mbar). RF-guiding techniques are used to extract the ions. During the postdoctoral work I used and modified this code to evaluate and optimize acceptance of the machine for different ions. It was used to design injection channel. The relativistic mover was implemented using Boris method. The beam envelopes were calculated to help design vacuum vessel. The beam optics calculation for beam passing through the A1900 separator was done using combination of two well known codes TRANSPORT and LISE++. The beam emittances were matched to the calculated acceptances.

Intense neutron source for experiments in accelerator physics, astrophysics and material science research is under construction at Stern Gerlach centre of Goethe University at Frankfurt am Main. I worked on this project to simulate beam transport through chopper system. I simulated space charge effects using Particle-in- Cell method. The numerical model includes simulation of production of secondary electrons and its effect on the pulse, simultaneous transport of multiple ion species, and effects on bunch shape from kicker pulse. A test experimental setup was also used to verify simulations which showed the space charge compensation through secondary electrons produced at beam dump.

My doctoral work was investigations on transport and storage of the high current ion beams. A storage ring with a longitudinal magnetic field was proposed for accumulation of intense ion beams. I developed numerical model using Particle-in-Cell method to calculate space charge effect using so called magnetic coordinates. A numerical model was also developed to study and compare experimental the low energy high current ion beam transport through curved sector magnets with toroidal magnetic field.

The ion beam diagnostics is one of the challenging topics. There exist various methods destructive and non destructive. Ion beam profile using rest gas interaction is one of the ways to acquire beam profile. Efforts were made in past to construct transversal profile of the beam by arranging CCD camera radially to acquire beam image and reconstruct beam profile commonly known as tomography. There has been recent development at University of Frankfurt on this subject.
The beam transport experiments in curved magnetic field, indicated necessity for unconventional type of diagnostics. I proposed for a ring device consisting photodiodes can be used to determine transversal beam profile. A circular ring with series of photodiodes was constructed and analyzed under a context of Bachelor thesis (Adem Ates, Uni. Frankfurt). The experimental results were shown to be in agreement with simulations.