Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. In nuclear engineering, a prompt neutron is a neutron immediately emitted by a nuclear fission event, as opposed to a delayed neutron decay which can occur within the same context, emitted by one of the fission products anytime from a few milliseconds to a few minutes later. Using U-235 as an example, this nucleus absorbs thermal neutrons, and the immediate mass products of a fission event are two large fission fragments, which are remnants of the formed U-236 nucleus. These fragments emit, on average, two or three free neutrons (in average 2.47), called "prompt" neutrons. A subsequent fission fragment occasionally undergoes a stage of radioactive decay that yields an additional neutron, called a "delayed" neutron. These neutron-emitting fission fragments are called delayed neutron precursor atoms. Delayed neutrons are associated with the beta decay of the fission products.

Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.