SHIELDING AGAINST INITIAL RADIATIONS FROM NUCLEAR WEAPONS (A State-of-the-Art Report on Shield Design Techniques)

摘要

Neutrons and gamma rays released by in-air detonations of nuclear weapons undergo various types of interactions with the surrounding en¬vironment, some of which result, in additional radiations being born at points far removed from the original burst location. In the absence of adequate weapons test data, designers of shields to attenuate the initial radiations (those born within the first minute) must rely on information gained from "transport" calculations performed on large electronic com¬puters. In such calculations the detonation and surrounding materials, including the proposed shielded structure, are mocked up as accurately as is possible and practicable, and the intensities of the radiations reaching specified locations within the structures are computed. Such calculations are extremely difficult and very time-consuming, and much of the shielding research effort during the past decade has been devoted to the development of adequate transport methods and of the necessary input data that describe neutron and gamma-ray infractions in the pertinent materials.