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labroid t1_j0sey7h wrote

Here's a video - the very end shows the lasers hitting the walls of the "package" holding the sphere with the fuel inside. The lasers hitting the walls raises their temperature so they produce X-rays. The X-rays ablate the outside of the fuel sphere, which flies outward. The inside of the sphere reacts to the ablation by blowing inwards, compressing the fuel.

If you do a couple google searches I'm sure you'll find an appropriate level explanation.

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kepler1 t1_j0tun81 wrote

"...the beams pass through the final optical assembly, which converts the infrared light into ultraviolet light..."

Um, what??!

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labroid t1_j0tz05w wrote

Yes! I was lucky enough to get a tour of the NIF, and I asked the guide what the conversion efficiency was of the UV conversion (as those can be pretty inefficient), and he said 50%. Think about that - you go through the whole multi-building-sized process of building hundreds of terawatts of laser beams, and the last step - like 25 feet from the target it looked like - you lose HALF of the energy to UV-upconversion. Then 90% of the X-ray energy is lost. So you've got to start with a LOT of laser power. See https://lasers.llnl.gov/about/how-nif-works/final-optics.

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nicethingslover t1_j1r5jrf wrote

u\labroid, your video sounds interesting but unfortunately the link doesn't work anymore. Do you have an alternative link?

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labroid t1_j1sl7n8 wrote

It looks like the site is under maintenance. I'd give it a couple days and try again....

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