London: Harrison & Sons, 1930. 1st Edition. BOUND FIRST EDITION OF THE FIRST DESCRIPTION OF THE FIRST PARTICLE ACCELERATOR TO BE INTENTIONALLY CONCEIVED. This paper describes the design and early operation of the first proton accelerator.
“The importance of Cockcroft and Walton’s work is enormous, not only because it gave an experimental proof that quantum mechanics was adequate to treat the nuclear processes, but also because, at the global level, it foreshadowed what was going to be the future of nuclear physics, and more generally, of the physics of elementary particles: no longer an isolated work, which could be done in any laboratory, but an organized enterprise, that was possible only in well-equipped centers, where the great accelerating machines could be built and operated” (Bruzzanti, Enrico Fermi,159).
Cockcroft and Walton’s “paper marks the beginning of the lines of evolution for particle accelerators. The starting point is located with nuclear protophysics in a 1930 paper [the offered paper] by Cockcroft and Walton: ‘It would appear to be very important to develop an additional line of attack on problems of the atomic nucleus. The greater part of our information on the structure of the nucleus has come from experiments with alpha particles and if we can supplement those with sources of positive ions accelerated by high potentials we should have an experimental weapon which would have many advantages over the alpha particle” (Cockroft and Walton, 1930, 477; ibid).
“The study of the scattering of charged particles has been, since the early years of the 20th century, the main tool for the experimental research in atomic and nuclear physics. However, the energy of the particles emitted in natural processes is quite small, and therefore it became necessary to design the particle accelerators, machines that dramatically changed high energy physics. One could say, establishing an analogy with an older and more familiar area of investigation, that the particle accelerators have allowed researchers to explore the structure of matter at smaller and smaller dimensions, as the telescope enlarged our knowledge of the universe at much larger scales” (Bruzzanti, 157-158).
“Cockcroft and Walton were among many scientists wanting to probe deeper into the fundamental structure of matter by penetrating the nucleus. Knowing that creating and maintaining a voltage that would allow them to accelerate alpha-particles to energies above those of radioactively-produced ’s was currently impossible, they looked to accelerate something lighter instead—protons.
“Cockcroft made estimations of the minimum energy required to penetrate a nucleus based on some calculations he found in an article circulating in the Cavendish Laboratory on the new theory of wave mechanics. The author of this article, George Gamow, a young Russian employed by Niehls Bohr’s Institute of Theoretical Physics in Copenhagen, theorized that a charged particle making a head-on collision with a nucleus has a chance of penetration (tunneling) even if it does not have as much energy as would be required by pre-wave mechanics physics (Gamow, 496).
“Cockcroft deduced that protons would be a better agent than alpha’, and that a proton with energy of 300 kilovolts (kV) would be about one-thirtieth as efficient against boron as an alpha from polonium would be against aluminum. He and Walton went straight to work. They initially used a 200 kV transformer to accelerate protons through a straight discharge tube. When this yielded no results, they concluded that they needed higher potentials.
“They decided to build a voltage multiplier consisting of a complicated set of capacitors connected to rectifying diodes acting as Figure 1. Cockcroft and Walton’s voltage multiplier (Cockcroft and Walton, 620). 4 switches. They discovered that by opening and closing these switches in various sequences they could achieve a potential of 800 kV from their 200 kV transformer. In 1932 they were vindicated when they used a potential of 500 kV to accelerate protons down a vacuum tube eight feet long towards a lithium target, and found that the protons disintegrated the lithium nucleus into two -particles This result was duplicated by a Soviet research team in Kharkov a year or so later. (Cockcroft and Walton, 621)” (Steere, A Timeline of Major Particle Accelerators, 1-2). Item #895
CONDITION & DETAILS: London: Harrison & Sons. Complete. 4to (Quarto). 10 x 7 inches (250 x 175mm). , v, , xxxviii. In text illustrations throughout. Handsomely bound in tan cloth; two gilt-lettered red morocco spine labels. Very tightly and solidly bound. Clean and bright inside and out. Very good condition.