%info@http:://golem.fjfi.cvut.cz/wiki/root/GW4reports

\def\GWslide{\slide{Tokamak mission: \\ to create $\mu$Sun in the terrestrial conditions}{
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%\GWig{width=\tw}{Theory/Fusion/FusionIntro/FusionReaction/fig/Landscape.png}
}
{0.55}{\GWig{width=1\tw}{Theory/Fusion/FusionIntro/TokamakMission/figs/reacteur_gb.jpg}}
\bc \DTreactionfull\\ The task: to heat (up to 100 million degrees) DT fuel and confine it (up to 30 years) in the high temperature plasma state of matter to produce He \& fusion energy.\ec
}
}

\def\default{
Tokamaks are machines with a strong magnetic field whose mission is to, one day, become fusion reactors fueling clean and safe power plants. The basic task of a tokamak reactor is to heat and confine its fuel, a 50:50 mixture of deuterium and tritium, allowing thermonuclear fusion reactions to take place. These reactions generate heat (14.1 MeV per reaction) which is subsequently converted into electricity via the standard steam-turbine cycle.
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One of the main challenges in current tokamak research is to confine the burning fuel. Although the fuel is very thin (its density is 5-8 orders of magnitude lower than the density of air), its temperature is extremely high, up to $\sim$100 million K. This is to ensure that when deuterium and tritium nuclei collide, they have sufficient energy to overcome the repulsive electrostatic barrier and fuse, hence \textit{thermonuclear} fusion. Such high temperatures mean that the fuel is in the state of plasma, a collection of ionized nuclei and free electrons, and also that it must never directly touch the reactor walls. (For one, the plasma would cool down and cease to exist; for two, the reactor walls might melt.) Tokamaks confine the fuel using the Lorentz force $q \textbf{v} \times \textbf{B}$, which forces charged particles to rotate around magnetic field lines rather than travel across them freely. Thus the strong magnetic field confines the plasma in the center of the tokamak chamber.}