The last few firings showed an odd "quiet period" of long stability in a system that otherwise appeared to prove itself unstable, but the experiment was generally thought to prove that pinch machines were unworkable, and the efforts with ZETA ended in 1958.
The last few firings showed an odd "quiet period" of long stability in the system, but the nature of these quiet periods, or "quiescence", was not fully researched. ZETA seemed to suggested that the pinch concept was simply unworkable, and the efforts with ZETA ended in 1958.