NIF achieves new fusion output milestone

Researchers at the National Ignition Facility (NIF) have taken another step toward their long-overdue goal of using lasers to attain a self-sustaining nuclear fusion reaction. On 14 June in Physical Review Letters, researchers described experiments that doubled previous records both for neutron yield (now at 1.9 x 10¹⁶) and fusion energy output (now at 54 kilojoules) generated from capsules containing cryogenic deuterium–tritium fusion fuel. The progress was due largely to changes to both the capsules and the hohlraums—cylinders in which the capsules are suspended—that helped maintain the symmetry of the fuel’s implosion.