National Ignition Facility

The National Ignition Facility , is a large laser-based inertial confinement fusion research device, located at the Lawrence Livermore National Laboratory in Livermore, California. NIF uses lasers to heat and compress a small amount of hydrogen fuel with the goal of inducing nuclear fusion reactions. NIF's mission is to achieve fusion ignition with high energy gain, and to support nuclear weapon maintenance and design by studying the behavior of matter under the conditions found within nuclear weapons. NIF is the largest and most energetic ICF device built to date, and the largest laser in the world.

The basic concept of all ICF devices is to rapidly collapse a small amount of fuel so the pressure and temperature reach fusion-relevant conditions. NIF does this by heating the outer layer of a small plastic sphere with the world's most powerful laser. The energy from the laser is so intense that it causes the plastic to explode, squeezing down on the fuel inside. The speed of this process is enormous, with the fuel reaching a peak around 350 km/s, raising the density from about that of water to about 100 times that of lead. The delivery of energy and the adiabatic process during collapse raises the temperature of the fuel to hundreds of millions of degrees. At these temperatures, fusion processes occur very rapidly, before the energy generated in the fuel causes it to explode outward as well.

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