Observation of Supersonic FRC Merging Process using Wide-View Visible-Light Tomographic Camera*

At Nihon University, experiments on the collisional merging experiments of Field-Reversed Configuration (FRC) have been conducted using the FAT-CM device. The time evolution of the internal structure during this collisional merging process, which is presumed to involve dynamic structural transitions, has not yet been observed. The tomographic camera (T-cam) has been developed to visualize FRCs through the imaging of visible light. While it has successfully reconstructed the internal structure of FRCs and determined the center of gravity of plasmoids during the translation process, it has been incapable of doing so during and after the collisional merging process due to its narrower field of view than the emission area. The observable range of the newly developed T-cam encompasses most of the area within the confinement chamber. This advancement is expected to enable the reconstruction of the collisional merging process and the subsequent state. This work reports the insights from the observations made using the newly built T-cam.