Study of cusp injection by a streak camera

Experiments were done in order to know interactions between high density hydrogen plasmas and magnetic fields. (cusped field, single coil field and mirror field) Behaviors of injected plasma were studied using streak photographs taken through a long slit imaged at the axis of the straight vacuum vessel. Experimental results are as follows. 1) Single coil field Plasma decreases its axial velocity in encountering strong field, and penetrates through it even when the field strength is more than 8,000 gauss. 2) Cusped field After penetrating through the entrance cusp, plasma takes back its original speed and goes through the zero region of the field with this constant velocity up to a certain point where the velocity changes abruptly. After then plasma moves toward the exit cusp and is reflected by a 6000-gauss field. 3) Mirror field Plasma injected into mirror field is not trapped. (author)