A doomsday devices - Neutron Bomb

Neutron bomb Samuel Cohen, the inventor of the neutron bomb, once described it as a 'discriminate weapon' as it kills all the people in its blast radius without decimating the buildings. It is the high-energy of the neurons that causes the killing blow, not the heat or nuclear fallout, allowing enemies to take the facilities of a city, without dealing with the pesky enemies that inhabit it.

A neutron bomb or officially known as one type of Enhanced Radiation Weapon is a low yield fission-fusion thermonuclear weapon (hydrogen bomb) in which the burst of neutrons generated by a fusion reaction is intentionally allowed to escape the weapon, rather than being absorbed by its other components. The weapon's radiation case, usually made from relatively thick uranium, lead or steel in a standard bomb, are instead made of as thin a material as possible to facilitate the greatest escape of fusion produced neutrons. The "usual" nuclear weapon yield—expressed as kilotons of TNT equivalent—is not a measure of a neutron weapon's destructive power. It refers only to the energy released (mostly heat and blast), and does not express the lethal effect of neutron radiation on living organisms.

Compared to a pure fission bomb with an identical explosive yield, a neutron bomb would emit about ten times the amount of neutron radiation. In a fission bomb at sea level, the total radiation pulse energy which is composed of both gamma rays and neutrons is approximately 5% of the entire energy released; in the neutron bomb it would be closer to 40%. Furthermore, the neutrons emitted by a neutron bomb have a much higher average energy level, closer to (14 MeV) than those released during a fission reaction (1–2 MeV). Technically speaking, all low yield nuclear weapons are radiation weapons, that is including the non-enhanced variant. Up to about 10 kilotons in yield, all nuclear weapons have prompt neutron radiation as their most far reaching lethal component, after which point the lethal blast and thermal effects radius begins to out-range the lethal ionizing radiation radius. Enhanced radiation weapons also fall into this same yield range and simply enhance the intensity and range of the neutron dose for a given yield.