Thermonuclear weapon

Multi-stage fusion-fission nuclear weapon

A thermonuclear weapon, fusion weapon, or hydrogen bomb (H-bomb) is a second-generation nuclear weapon, using nuclear fusion. The most destructive weapons ever created, their yields typically exceed first-generation nuclear weapons by twenty times, with far lower mass and volume requirements. Characteristics of fusion reactions can make possible the use of non-fissile depleted uranium as the weapon's main fuel, thus allowing more efficient use of scarce fissile material.

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