Tritium consists of about 4.5 kilograms of plutonium-239. Since tritium undergoes radioactive decay, and is also difficult to confine physically, the much larger secondary charge of heavy hydrogen isotopes needed in a true hydrogen bomb uses solid lithium deuteride as its source of deuterium and tritium, producing the tritium "in situ" during secondary ignition. During the detonation of the primary fission bomb stage in a thermonuclear weapon (Teller-Ullam staging), the sparkplug, a cylinder of U-235/Pu-239 at the center of the fusion stage(s), begins to fission in a chain reaction, from excess neutrons channeled from the primary. The neutrons released from the
Radioactive Isotope Beam Factory atomic magic numbers. Radioactive Isotope Beam Factory The Radioactive Isotope Beam Factory is a multistage particle accelerator complex operated by Japan's Nishina Center for Accelerator-Based Science which is itself a part of the Institute of Physical and Chemical Research. Located in Saitama, the RIBF generates unstable nuclei of all elements up to uranium and studies their properties. According to physicist Robert Janssens, ""[it] can produce the most intense beams of primary particles in the world."" RIBF took ten years to construct and its Superconducting Ring Cyclotron (SRC) can achieve energies of 2,600 MeV. Work at the RIBF has contributed to