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How do fusion bombs achieve "ignition"? It's not with lasers, right?

Also, couldn't the net energy from the ignition be used to continue the reaction, so you only need the lasers for startup?

Sorry for the newb questions, just curious.

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Caveat: This comment is derived from publicly available info. An H-bomb is a two part bomb. The primary bomb is a implosion plutonium bomb similar in make to the nagasaki/trinity bomb. It is theorized the Xrays from that bomb are focused on a secondary cylinder of uranium-238 that has a core of hydrogen and/or lithium. The Xrays ablate this casing at such intensity that the inward force (the opposite force of the ablation) is strong enough to propell the casing inwards at 300 km/second. This squeezes the hydrogen/lithium and causes fusion which releases a tone of energy, but more importantly a huge amount of neutrons. These neutrons cause the 238 in the casing to fission releasing an even greater amount of energy. A Neutron bomb for example replaces some/all of the 238 with lead, so the neutrons escape without causing more fision. Again, this is all speculation from scientists outside the various labs, and using publicly available information.

For power generation, since the energy from any fusion reaction is primarily emitted as heat and neutrons. The neutrons are difficult to utilize and is basically wasted energy, but the heat would just heat water, turning it into steam, then turning a turbine.

With a fission bomb.

Don’t have a good explanation for your second question, although I think the short answer is “not with the way the Livermore experiment was set up.”

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