The laser efficiency alone keeps ICF reactors as a pie in the sky. p-B11 is attractive but the Bremsstrahlung emissions of the heavy/highly ionized boron would exceed the power output of a steady state reactor. So knock on neutrons all you want: until you bridge 10 orders of magnitude aneutronic fusion won't be supplying anyone with power.
Keep up the good work, but don't expect results in your lifetime.
HB11 is proposing to use an "avalanche" mechanism where alpha particles from the fusion run into and accelerate protons to energies > thermal to continue the reactions (a chain reaction).
Unfortunately, this doesn't appear to work, by about two orders of magnitude.
Their proposed direct conversion scheme is also problematic, for several reasons (electrons would short out the spherical capacitor, the necessary ion current greatly exceeds the space charge limit on the current, and the alpha particles from p-11B are not monoenergetic, especially after the scattering necessary for their putative avalanche scheme, meaning that ions would either not have enough energy to reach the collecting electrode or would reach it with so much kinetic energy the surface of the electrode would experience too much heating.)
The technical hurdles to inertial confinement fusion are so absurd. Even were the output energies substantial enough to justify the cost of a production generator it would take decades to have a functioning mechanism to deliver the fuel with beam integrity. Physicists are amazing at trivializing engineer feats and love nuclear weapons funding.
This is weapons research and that's it, talking about any other scientific validity has always been a weak attempt to give it some moral ground
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[ 2.3 ms ] story [ 36.9 ms ] threadhttps://news.ycombinator.com/item?id=30841080
Keep up the good work, but don't expect results in your lifetime.
Unfortunately, this doesn't appear to work, by about two orders of magnitude.
https://iopscience.iop.org/article/10.1088/1361-6587/abf255
Their proposed direct conversion scheme is also problematic, for several reasons (electrons would short out the spherical capacitor, the necessary ion current greatly exceeds the space charge limit on the current, and the alpha particles from p-11B are not monoenergetic, especially after the scattering necessary for their putative avalanche scheme, meaning that ions would either not have enough energy to reach the collecting electrode or would reach it with so much kinetic energy the surface of the electrode would experience too much heating.)