Charged-particle stopping powers in inertial confinement fusion plasmas

The effects of large-angle scattering, important for plasmas for which the Coulomb logarithm is of order 1, have been properly treated in calculating the range (R) and the ρR (the fuel-areal density) of inertial confinement fusion plasmas. This new calculation, which also includes the important effects of plasma ion stopping, collective plasma oscillations, and quantum effects, leads to an accurate estimate, not just an upper limit of ρR. For example, 3.5 MeV α’s from D-T fusion reactions are found to directly deposit ≃47% of their energy into 20 keV deuterons and tritons. Consequently the α range (R) and ρR are reduced by about 60% from the case of pure electron stopping.