[leephillips]

NIF people like to call this the “target gain”, but someone there has been whispering “net gain” to the journalists, in their ongoing campaign of deliberately deceptive hype. But “target gain” isn’t even (pellet output)/(laser output). The denominator is laser energy deposited in the hohlraum; the rest of it doesn’t count. And this deposited laser energy is estimated based on a model of laser deposition—it’s not measured. (At least, this is the way it was the last time I bothered reading a paper from NIF. I got bored with it a while ago.) The modeling codes are classified; no one without a need to know gets to examine them, and they are not well benchmarked. So the actual target gain is likely < 1 in any case.

[dmix]

> The modeling codes are classified

What is the justification for keeping it classified?

[zardo]

NIFs purpose is to validate simulations of thermonuclear weapon detonations. The default is going to be classified, it's making something public that would have to be justified.

[Schroedingersat]

Because it's a weapons program that is entirely unrelated to power generation.