[en] It was found that a diagnostic Hg beam can be used to determine the geometry and parameters of an essential element of the EBT concept, the ELMO rings. Consequently, an (IT)² diagnostic system would be of immense help in the EBT development program, particularly in assessing the impact of ring properties and power requirements on the overall economic feasibility of EBT reactors. The results of this study indicate strongly that an (IT)² system can not only measure the changes in ring geometry as the experimental parameters are varied, but also detailed spatial distributions of the temperature and density of the hot ring electrons. The (IT)² diagnostic system is the only method to date which appears to have the potential to perform directly these detailed measurements of the ring profiles. Furthermore, the Hg beam itself may find useful application as a heavy ion beam probe for measurements of the space potential of the confined plasma in EBT and as a tool to determine the magnetic field configuration within the ring