In 1954, the ZETA project began at Harwell in the U.K. ZETA stands for Zero Energy Thermonuclear Assembly. The U.K. had built a number of devices to test the concept of the zeta-pinch which used magnetic fields generated by induced electrical currents to compress a plasma. ZETA was the first large scale nuclear fusion reactor built. The U.S. had also been working on pinch devices as well as stellarator machines as a path to nuclear fusion. The construction of the ZETA was seen as a major leap forward in fusion research, putting the U.K. ahead of the U.S. In the same year, Edward Teller, a theoretical physicist gave a talk in which he concluded that most proposed designs for magnetic confinement of plasmas would be unstable.
In 1956, it was revealed that the U.S.S.R. was working on tokamak systems at the Kurchatov Institute in Moscow. Their experiments were encountering problems similar to those found in the U.K. and U.S. experiments. This revelation stimulated discussions on the public release of classified fusion research documents by the U.S. and the U.K. That same year, Friedwardt Winterberg, a physicist at the University of Nevada suggested that a fusion reaction could be initiated by a convergent shockwave.
In 1957, ZETA went into operation. Neutrons were generated during each test which was a strong indication that nuclear fusion had occurred. Temperatures reached five million degrees during the experiments with ZETA. The results of the experiments matches the theoretical models of fusion. However, researchers in the U.S. conducted their own experiments and concluded that the temperatures were not correctly measured and that neutrons could be produced that were not indicative of fusion. The enthusiastic announcements of the U.K. ZETA researches had to be withdrawn which resulted in a lack of confidence in the "pinch" route to nuclear fusion. By 1961, most work on using zeta pinch to generate fusion had ended. Although the first ZETA experiments failed to produce fusion, the machine did continue to be used for plasma pinch research and produced a number of important and useful results.
In 1958, a great number of research documents were shared by the U.K., the U.S.S.R. and the U.S. at the Atoms for Peace conference in Geneva. This was the biggest conference on fusion research held to date. One conclusion of the shared research was that the basic pinch approach was not successful.
In 1963, Friedwardt Winterberg proposed bombarding a mixture of liquid 2H (deuterium) and 3H (tritium) with micro-particles which had been accelerated to one thousand kilometers per second. Winterberg made many contributions to nuclear fusion theory as well as designing some of the hardware used in fusion research. He also proposed a nuclear fusion propulsion system for spacecraft called the Winterberg/ Daedalus Class Magnetic Compression Reaction Chamber which was built at the University of Alabama. Winterberg continued to be active in fusion research and development for decades.
ZETA machine:
