The oak ridge thermonuclear program-recent advances on the DCX

In the Oak Ridge thermonuclear experiment, 600. kev molecular ions of hydrogen or deuterium are injected into the median plane of a direct current magnetic mirror machine (DCX). A fraction of the molecular ions is dissociated (H²⁺ → H⁺ + H^o) as the ion beam passes through a high-energy carbon arc whose electrodes are located at each end of DCX. The magnetic field configuration is such that the 300-kev atomic ions thus created are trapped by virtue of the change in charge-to-moss ratio and enter a circular orbit concentric with the magnetic axis. The neutral atoms and the remaining undissociated molecular beam leave the machine. Loss processes, principally charge exchange collisions suffered by the circulating ions, have thus far prevented achieving the appreciable plasma density required for observable fusion reactions. Plasma densities In the order of 10⁺¹⁰ ions/cm³ and mean containment times of 10 to 12 msec have been observed. The experimental program at the present time is one of diagnostic measurements on the trapped ions and their environment, and of building up the plasma density by increasing the trapping rate and containment time.