Nuclear Technology

Nuclear Technology (核技術) is technology involving the of, the most notable being  and.

Given the circumstances surrounding this subject in the Toaru series, this page covers instances of nuclear technology appearing or being referenced within the series, as well as other technologies and subjects tied to nuclear technology or nuclear physics featured within the story.

Principles
The sign used to indicate nuclear and radiation hazards is a black fan, made from three triangular fans (two above and one below) around a small circle, over a yellow background.

Nuclear Physics
Two key nuclear reactions are Kaku Yūgō (核融合) and Kaku Bunretsu (核分裂). As their names suggest, nuclear fusion involves the combination of atomic nuclei while fission involves the splitting of atomic nuclei, with the mass difference between reactants and products resulting in the release or absorption of energy. Lighter elements such as and  are generally more fusible, while heavier elements like  and  are more fissionable. Under the right circumstances, a single nuclear reaction can cause an average of one or more subsequent reactions, leading to the possibility of a self-propagating series of such reactions, what is known as a.

Nuclear fusion is the reaction which generates the power produced by the Sun and other stars.

Another associated process is (also known as nuclear decay or ), where an unstable atomic nucleus loses energy via radiation - a material containing such unstable nuclei considered radioactive. The three most common types are (α),  (β), and  (γ). Of the particles released during the first two, an consists of two protons and two neutrons bound as in a helium nucleus, while a  is a high-energy/speed electron or positron. s, a penetrating form of electromagnetic radiation with the shortest wavelength of electromagnetic waves, are emitted in the latter of the three. Nuclear radiation is harmful to, one of the hazards associated with nuclear technologies, and although the circumstances under which they can inflict the most harm differ, all three of these common types of radiation are no exception.

Nuclear Reactors
A nuclear reactor (原子炉) is a device and vessel in which a nuclear reaction is contained and controlled, often for the purposes of electrical power generation.

In a common nuclear fission reactor, fissile material is inserted into the reactor's core in the form of fuel rods, while control rods are inserted or removed in order to control the rate of nuclear fission.

Some reactors are used to power large naval vessels, such as aircraft carriers (an example being the US's Hubble Lotus ) and submarines (including the ones used to carry nuclear missiles).

Although nuclear-related power generation in space probes typically comes from using radioactive decay (e.g. ), Russia has been continuing research into developing a 'clean' nuclear reactor for use in space, despite an incident involving a reactor-powered satellite falling back to Earth.

Academy City has only one nuclear reactor, in a nuclear research facility in School District 10. It was anticipated that research on Meltdowner would have applications in non-laser nuclear fusion reactors.

Nuclear Weapons
Nuclear weapons (核兵器), also referred to as nukes for short, are which involve the use of nuclear reactions.

Typical nuclear weapons involve setting off an out-of-control nuclear chain reaction (either nuclear fission or nuclear fusion) within the reaction materials within and releasing immense amounts of energy in an explosive detonation. They can come in the form of nuclear bombs (also referred to as atomic bombs (原爆), with nuclear fusion bombs also called hydrogen bombs (水爆) from the element used in the nuclear fusion), or warheads mounted on ballistic missiles, also referred to as nuclear missiles (many launch-ready ones being stored in missile silos or nuclear submarines).

Given the devastating power and consequences associated with nuclear weapons, there are strict restrictions on their possession and deployment by international law. Among weapons of mass destruction, they are included in the and  classifications (N for nuclear, B for biological, C for chemical and R for radiological).

Two named examples of nuclear weapons featured in the story are the Opasnosti strategic nuclear warheads (known as the Nu-AD1967 in America) and Solntse hydrogen bomb, both of Russian ( in the case of the former) origin.

Other
There are applications of nuclear technology for medical purposes, referred to as. One tool associated with this field is a, which utilizes gamma radiation.

Although Academy City only has one nuclear reactor, there is apparently a radiation release hazard associated with misuse of the Hula Hoop particle accelerator.

There are structures which are built to withstand the effects and fallout of nuclear weapons to a certain extent, some designated nuclear shelters or nuclear bunkers. Notably, the Windowless Building, home to Academy City's Board Chairman Aleister Crowley, was said to be capable of withstanding a direct nuclear attack.

The immense power associated with nuclear weapons and nuclear reactors is sometimes used as a benchmark in comparisons with technologies, supernatural powers and other subjects possessing a similar level of power.

Background
Scientific discoveries pertaining to the phenomena that nuclear technologies would utilize were made in the early part of the 20th century. During World War II, the worked to develop nuclear weapons for the Allies, with the first artificial nuclear reactor and first human-made self-sustaining nuclear chain reaction being achieved in 1942, eventually leading to the first and at present only use of nuclear weapons in armed conflict, the 1945, which resulted in Japan's surrender and the conclusion of the war in Asia. Nuclear technologies developed further during the subsequent between the United States and the, accompanied by a build-up of nuclear weapons and an escalation in their destructive power.

Following the end of the Cold War and the collapse of the Soviet Union, nuclear warheads leaked from Russia, with the nuclear material being exchanged from the original outer shell to a new one to bypass the security lock and confirmation code required for detonation. Organizations seeking independence from Russia created these exchanged warheads, but Russia later hunted them down in special military operations. Although official records stated they were dismantled and the material reused as reactor fuel, a number (Opasnosti) were kept as 'reserves' which could be fired at any time without permission from the president.

At some point in the past, Russia launched a satellite with a nuclear reactor, but lost control with the satellite falling back to Earth, though they continued research into nuclear reactors for use in space.

A few years before the British Halloween, under the influence of the Roman Catholic Church, the European Union adopted a treaty that specifically banned the weapons the United Kingdom had been developing, as well as their nuclear weapons, which would be given to France who would be the sole possessor of nuclear weapons within the EU and have the technology needed for safe disassembly, with the official reason a cover to the actual intent to undermine the UK.

British Royal Family Arc
During Princess Carissa's coup d'état, France had a nuclear submarine hidden in the Strait of Dover with a nuclear missile aimed at London.

World War III Arc
During World War III, officials in Moscow were concerned about the possibility of Academy City seizing Russia's nuclear silos and activated the Kremlin Report, the manual for their defense, measures including dissemination of a bacteriological weapon.

In the latter stages of the war, Nikolai Tolstoy attempted to have an independent military under his command fire Opasnosti strategic nuclear warheads against the Star of Bethlehem after Fiamma of the Right betrayed him, despite the repercussions of exploding a nuclear weapon at that altitude. The attempt failed due to the intervention of Misaka Mikoto and Misaka 10777.

Magic God Invasion Arc
In the Alpha World, Academy City's supply lines were cut off through the use of nuclear landmines.

Operation Handcuffs Arc
During the events of Operation Handcuffs, it was noted that the discharge machine oil that Ladybird used, reducing frictional wear on her joints and allowing her to safely release excess energy as a room temperature superconductive fluid, would put the building of a manned space probe within reach when combined with an outer space nuclear reactor.

Los Angeles Arc
While talking about space travel and beliefs that set in with state-run programs, Othinus refers to the Russian belief that nuclear energy made for a clean power system, how they once launched a running nuclear reactor into zero-G space but lost control, with the satellite falling back to Earth, and how they still continued research into developing a clean nuclear reactor for use in space.

Level Upper Arc
During the AIM Burst's rampage, it threatened Academy City's sole nuclear facility in School District 10.

Toaru Kagaku no Railgun SS2: Ability Demonstration Trip
Much of the events surrounding Misaka Mikoto's visit to the Russian Shopping Center, involved a plot by at least two Academy City cooperative institutions to destroy the city with a Solntse hydrogen bomb, ultimately thwarted. Besides the real threat of the hydrogen bomb itself, these events included rumors of a ornmanent, and false rumors spread by the shopping center higher-ups that the Level 5 had brought a nuclear weapon, setting a mob after her. When faced with the hydrogen bomb, units in Academy City were forced to rely on older manual methods of disarmament and dismantling, as the methods of bomb disposal more prevalent in Academy City, such as using chemical agents to change the composition of the explosives to something safe or relocating it to an area where it could be safely detonated, could not be used in this case.