Undergo a special radiation process before they are deployed
...receive a small amount of material that can undergo fusion (deuterium and tritium) that is placed inside the core of the fission device
...use the fusion of heavy isotopes of hydrogen, deuterium, and tritium to release large numbers of neutrons
...are much more complicated and evolved and contain active safety measures
...have not been developed in the last decades because of the lack of demand
...are much simpler and have built-in passive safety measures
...is highly accessible to state and non-state actors
...forces the lighter U-238 to the top of the centrifuge, where it can be "scooped off"
...exploits the mass difference between U-235 and U-238
To obtain large quantities of Uranium 238
To increase the percentage of Uranium 235, a fissionable material, in a given mass of uranium
To mix Uranium with Plutonium in a dedicated facility
...a common practice in all countries possessing nuclear power plants
...a hotly debated topic with respect to the future of nuclear energy
...forbidden under international law
Materials whose nuclei can break apart when bombarded with neutrons, emitting more neutrons than they absorb
Materials whose nuclei never break apart when bombarded with neutrons and never release any neutrons
New materials that emerge as byproducts after a nuclear reaction
…fires two sub critical masses into one another to form one supercritical mass
…is a nuclear weapon delivered by a huge gun
…uses Plutonium to create an explosion
...use thermal energy to boost the power of the weapon
....have very clear limits to their yield
...use a fission trigger to set off a separate stage of fusion
United States, Sweden, France, Israel
United Kingdom, Switzerland, Argentina, Pakistan
Russia, South Africa, North Korea, China
10 kg of HEU and 2 kg of Plutonium
20 kg of Uranium and 5 kg of Plutonium
25 kg of HEU and 8 kg of Plutonium
The smallest entity known to humanity
A key component of every nuclear weapon
The basic building bloc of all material
A nuclear mass
A critical mass
A sub-critical mass
75 tons of low-enriched uranium
2 tons of weapons-grade plutonium
25 tons of highly-enriched uranium
Uranium and Fermium
Americium and Plutonium
Plutonium and Uranium
...requires the construction of large and relatively visible facilities
...is almost impossible for 99% of all states
...is easy and inexpensive
Enrichment and Reprocessing
Conversion and Fuel Fabrication
Mining and Milling
Heavier gas travels faster than lighter gas
Centrifuges are highly sensitive pieces of equipment
Lighter gas travels faster than heavier gas
By the Russians at Novaya Zemlya in October 1961
By the US at Alamogordo, New Mexico, in July 1945
By the French in the French Sahara in February 1960
Gun-type device
Hydrogen device
Implosion device
Highly radioactive and give off a lot of heat
Barely radioactive and can be easily handled
Slightly radioactive and extremely cold