Types of Nuclear Weapons

The distinction between these two types of weapons is blurred because they are combined in almost all advanced modern weapons. For example, a smaller fission bomb is first used to create necessary conditions of high temperature and pressure which are required for fusion. Similarly, fusion elements may also be present in the core of fission devices as well because they generate additional neutrons which increase efficiency of the fission reaction. Further, most of the fusion weapons derive substantial portion of their energy from a final stage of fissioning which is facilitated by the fusion reactions. The simplest nuclear weapons are pure fission bombs. They were the first type of nuclear weapons built during the American Manhattan Project and are considered as a building block for all advanced nuclear weapons. 

Other specific types of nuclear weapons are commonly referred to by their names such as neutron bombs (enhanced radiation weapons), cobalt bombs and salted bombs. The atomic bomb was the first nuclear weapon to be developed, tested and used. It was developed under the direction of American physicist J. Robert Oppenheimer (1904—1967) and implemented toward the end of World War... 

The destructive power of nuclear weapons derives from the core of the atom, the nucleus. One type of nuclear weapon, the fission bomb, uses the energy released when nuclei of heavy elements such as plutonium fission (split apart). A second even more powerful type of nuclear weapon, the fusion or hydrogen bomb, uses the energy released when nuclei of hydrogen are united (fused together). 

By Security Council resolution 687 the IAEA was entrusted, inter alia, with the task of carrying out immediate on-site inspections of Iraq s nuclear capabilities based on Iraq s declarations and on the designation of additional locations by the Special Commission established pursuant to Paragraph 9(b) of that resolution. Pursuant to the resolution, Iraq was to submit to the Secretary General of the United Nations and to the Director General of the IAEA within 15 days of adoption of the resolution, a declaration of the locations, amounts and types of nuclear weapons, nuclear weapons-usable material and any subsystems or components and any research, development, support or manufacturing facilities related to nuclear weapons or nuclear weapons-usable material. 

Perhaps you are familiar with the terms nuclear fission and nuclear fusion. Nuclear fission is the process by which a relatively massive nucleus is divided into smaller nuclei and one or more neutrons. Nuclear fission is the process that generates so much power in nuclear power plants and in certain types of nuclear weapons, such as the bombs that were dropped on Japan in 1945. The following equation shows an example of nuclear fission (the nuclear fission of uranium-235) ... 

At least two types of nuclear weapons can be built and fielded without any kind of... 

Tucked away on a high mesa in northern New Mexico, the Los Alamos complex constituted a third major facility of the Manhattan Project. This weapons research-and-development center, renamed after the war the Los Alamos Scientific Laboratory, had been the key meeting ground for scientists working on the bomb, and it remained the major facility for development of atomic weapons. The University of California operated it for the AEC. In 1950 the agency contracted with the university to open a second weapons-research center in Livermore, California, near San Francisco. The Livermore Laboratory concentrated on developing new and improved types of nuclear weapons. Since the university had been a pioneer in atomic research, it was a logical contractor for those facilities. 

IMPLOSION DEVICE IMPLOSION WEAPON. A type of nuclear weapon whose design features a spherical device that contains a quantity of fissionable material slightly helow critical mass at ordinary pressure. At detonation, the device undergoes implosion,having its volume suddenly reduced hy compression brought about by chemical explosives. The compression takes the fissionable material to a supercritical mass, and a nuclear explosion ensues. Plutonium is often used as the fissile material in such a design. Fat Man, the bomb dropped on Nagasaki, is an example of an implosion device. 

The neutrons in a research reactor can be used for many types of scientific studies, including basic physics, radiological effects, fundamental biology, analysis of trace elements, material damage, and treatment of disease. Neutrons can also be dedicated to the production of nuclear weapons materials such as plutonium-239 from uranium-238 and tritium, H, from lithium-6. Alternatively, neutrons can be used to produce radioisotopes for medical diagnosis and treatment, for gamma irradiation sources, or for heat energy sources in space. 

In plutonium-fueled breeder power reactors, more plutonium is produced than is consumed (see Nuclearreactors, reactor types). Thus the utilisa tion of plutonium as a nuclear energy or weapon source is especially attractive to countries that do not have uranium-enrichment faciUties. The cost of a chemical reprocessing plant for plutonium production is much less than that of a uranium-235 enrichment plant (see Uranium and uranium compounds). Since the end of the Cold War, the potential surplus of Pu metal recovered from the dismantling of nuclear weapons has presented a large risk from a security standpoint. 

The NRC also imposes special security requirements for spent fuel shipments and transport of highly enriched uranium or plutonium materials that can be used in the manufacture of nuclear weapons. These security measures include route evaluation, escort personnel and vehicles, communications capabiHties, and emergency plans. State governments are notified in advance of any planned shipment within their state of spent fuel, or any other radioactive materials requiring shipment in accident-proof. Type B containers. 

Even the ability of nuclear weapons to release radioactivity has been exploited to create different types of weapons. Clean bombs are weapons designed to produce as little radioactive fallout as possible. A hydrogen... 

Recognizing that the cessation of all nuclear weapon test explosions and all other nuclear explosions, by constraining the development and qualitative improvement of nuclear weapons and ending the development of advanced new types of nuclear... 

A second type of chemical weapon is rather new but has already attracted considerable military interest throughout the world—the large-scale use on the battlefield of chemicals which are not basically lethal in themselves but which produce a temporary and reversible incapacitation—for example, temporary mental confusion, temporary anesthesia, narcosis, paralysis, temporary blindness. Such chemicals used in conjunction with other nonnuclear arms could contribute to the success of a military operation, with a significant reduction in loss of life—particularly in comparison to the casualties associated with nuclear use. A situation where nonlethal weapons might be of considerable significance is found in so-called limited wars, or less than total wars, where military operations are limited in scale, area, participants, and degree of violence. In such wars it is desirable to stamp out aggression at the earliest possible moment and with minimum loss of life and property. 

Size Reduction The dismantlement of nuclear weapons results in many thousands of pounds of plastic bonded explosive (PBX) waste in an assortment of hemisphere sizes and odd pieces. The PBX types of interest are PBX-9404, PBX-9501, LX-10, and LX-04. Size reduction is important in the subsequent destruction or recycling of this PBX waste. 

The type of nuclear explosion produced by a nuclear weapon cannot occur in a nuclear reactor. The concentration of fissionable materials in a reactor is not sufficient to form a supercritical mass. 

This chapter on the effects of the explosion of nuclear weapons has been inserted in a book primarily concerned with the safety of nuclear installations for two reasons. Firstly, those concerned with nuclear safety may be asked questions on the effects of nuclear bombs (perhaps in discussions concerning the differences between the effects of an hypothetical accident of extreme severity in a nuclear reactor and those of the blast of a nuclear bomb). Secondly, because it may be useful, in general, to have a complete picture of the risks of various nuclear applications and of possible types of defence. 

The reprocessing involves separating the fission products from the actinides, and then separating the plntoninm from the uranium. The best known procedure of this type is the PUREX (Plutonium, URanium Extraction) process that is used for recovery of uranium and plutonium from irradiated fuel (see details in Chapter 2). The separated plutonium can be used for the production of nuclear weapons or converted into the oxide form, mixed with nraninm oxide and can be used as MOX nuclear fuel. 

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