TrapCad - Plasma simulation code    

download demo version TrapCad_demo.exe with built-in input files and the HELP-file, TrapCadHelp.chm

Important note! For faultless running check the properties of the files and unblock the security restraint if needed.


The original TrapCAD code was developed in the 90s to visualize the magnetic field line structure of Electron Cyclotron Resonance (ECR) ion sources and to simulate the motion of individual charged particles in magnetic traps. The upgraded version of the code retains these features and provides a user-friendly graphical interface and some new functionalities.


TrapCAD requires two input files containing the magnetic field data generated by solenoid coils and a multipole magnet. These files can be made by the user or by the SUPERFISH code. The input files contain the value of the magnetic induction (B) in discrete points of a grid.


The magnetic trap is represented by a cylinder and its longitudinal axis corresponds to the z-axis of a cylindrical coordinate system. On the window of the application the schematic front and side views of the magnetic trap are displayed. In the front view of the chamber one can move on the (r-φ) plane at a constant z-coordinate value. It is also possible to move along the z-axis. This way any points of the chamber can be reached.


The various functions of the application can be launched through the menu options or by keyboard shortcuts. The main outputs are the 14 generated text files, which allow the study of some problems using graphical codes as post-processors. Some of the files contain the initial and final attributes of the particles (positions, energies, etc.), some contain other information about the whole system (resonant zone, magnetic map file, etc.).


The figures shown below are only a few examples of problems that can be studied with the help of the output files generated by the TrapCAD. These figures were presented in the ECRIS '06 conference and the paper will be published soon.


Related publications:


Biri S. , Vámosi J.: 3D design and visualization of complex magnetic traps.

Proceedings of the 4th European Particle Accelerator Conference (EPAC). June 27 - July 1, 1994, London, United Kingdom. Word Scientific 2 (1994) 1432 [reprint]


Vámosi J., Biri S.: TrapCAD - a tool to design and study magnetic traps of ECR ion sources.

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 94 (1994) 297 [link]


Biri S., Valek A., Vámosi J.: Status of ECRIS building and recent results of trap modeling.

Proceedings of the 12th International Workshop on ECR Ion Sources. Tokyo, Japan, 25-27 April 1995. Eds: M.Sekiguchi, M., T.Nakagawa. Tokyo, RIKEN. INS-J-182 0 (1995) 207 [reprint]


Biri S., Vámosi J., Stiebing K. E., Schmidt-Böcking H.: Simulation of HCI movement in magnetic traps of ECR ion sources.

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 98 (1995) 553 [link]

Vámosi J., Biri S.: TrapCAD - program to model magnetic traps of charged particles.

Computer Physics Communications 98 (1996) 215 [link]


Biri S., Vámosi J.: Design aspects of the Debrecen ECR ion source.

Review of Scientific Instruments 67 (1996) 971 [link]

Biri S., Derzsi A., Feket É.,  Iván I.:  The upgraded TrapCAD code.
            High Energy Physics and Nuclear Physics - Chinese Edition Supplement 31 (2007)165. [link]


Maunoury L., Pierret C., Biri S., Pacquet J. Y.: Studies of the ECR plasma using the TrapCAD code.

            Plasma Sources Science and Technology 18 (2009) 015019 [link]


Biri S., Rácz R., Imrek J., Derzsi A., Lécz Zs. : Imaging of ECR plasma by computer simulation. 

            IEEE Transactions on Plasma Science 39 (2011) 11/2474-2475 [link]


S. Biri, R. Rácz, Z. Perduk, I. Vajda and J. Pálinkás: Recent developments and electron density simualtions at the Atomki 14.5 GHz ECRIS.   
            20th Int Conf. on ECRIS, Sidney, Australia, 2012. [talk]