The US$3.5 billion National Ignition Facility (NIF), at the Lawrence Livermore National Laboratory in Livermore, California, is designed to crush tiny pellets of hydrogen isotopes until they fuse into helium. The goal is to release more energy than goes into the pellet and in doing so roughly mimic conditions inside a modern nuclear warhead.
That was the goal, but a six-year “ignition campaign” came up short in September, sparking introspection amongst scientists, federal officials and congressional funders. Introspection in Washington inevitably leads to reports, and in November and December, a series of reviews of the project were released—including plans to shift the giant laser facility away from ignition work and towards weapons.
The gist of the conclusion given in the committee report is in this paragraph:
The important conclusion from the NIC is that the pressent understanding of the physics of the hahlraum and capsule implosion as embodied in modeling and computer simulation is insufficient to predict the results of the implosion experiments aimed at achieving ignition. Reviewers indicated that, while progress towards ignition had been made, a program of scientific experiments and modeling focused on understanding the various physical effects, in isolation, that impact the integrated implosion experiments provides the best approach to eventually either achieve ignition, or to understand definitively why it may not be achievable with indirect drive using the NIF laser. Executing such a program will also require enhancing the number of diagnostic measurements of both the future focused experiments and integrated implosion experiments.
The ignition program certainly has a major task ahead of it, and this failure to initiate ignition certainly generates even strong skepticism of its program.
Zz.
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