A comprehensive parametric experimental study of inertial electrostatic confinement plasma in two different external magnetic field configurations

An experimental study of plasma behavior in a cylindrical inertial electrostatic confinement (IEC) device has been carried out in the presence of an external magnetic field to investigate its effect on the various plasma parameters. The magnetic field was mapped in both axial and radial directions using a Hall probe, and its influence on plasma parameters was examined using Langmuir and Mach probe diagnostics. Mach probe measurements confirmed the presence of E × B drift around the cathode grid. Radial profiles of floating potential, electron temperature, and ion density were obtained for varying cathode voltages and magnetic field strength, as well as orientation. In the cusp configuration, the floating potential inside the cathode region becomes more negative due to the magnetic mirror effect and electron cusp losses, while in the uniform field case, the potential shifts from negative near the cathode to less negative or positive values near the wall. Electron temperature decreases in both configurations with increasing magnetic field strength, with a more steady profile observed under uniform field conditions. Ion density increases by nearly two orders of magnitude in the uniform field, compared to about one order in the cusp field. These results confirm that an external magnetic field enhances confinement of electrons, which in turn substantially enhances plasma density, providing a pathway toward improved neutron yield in IEC devices.