> You need a lot of energy to overcome the Coulomb barrier for boron - apparently at least 148 keV [1]. For a proton to have that much kinetic energy it needs t

> You need a lot of energy to overcome the Coulomb barrier for boron - apparently at least 148 keV [1]. For a proton to have that much kinetic energy it needs to be going at 5340 km/s [2]. "The exhaust velocity of a [pulsed plasma thruster] is of the order of tens of km/s" [3]. So what gives? I'm guessing that exhaust velocity figure is for heavy ions, but are protons really that much faster? This isn't necessarily a satisfying answer, but in their patent they mention "laser-assisted fusion": > In addition, a plurality of pulsed lasers are utilized to focus on focal regions of the exhaust region to catalyze boron fusion events...The pulsed lasers are modulated to create a superposition and constructive interference region where fusion is likely to incur in the reaction region. The plurality of pulsed lasers assists fusion ignition and/or further energizes the protons frame to assist fusion reaction. It is an insight of this invention that acceleration of particles using multiple small lasers would be helpful as only small hot regions of plasma are necessary for measurable fusion results. https://patents.google.com/patent/US20240018950A1/en https://patents.google.com/patent/US20240018950A1/en