Temperature equilibration of hydrogen is studied for conditions relevant to inertial confinement fusion .
New molecular-dynamics simulations and results from quantum many-body theory are compared with Landau-Spitzer ( LS ) predictions for temperatures T from 50 eV to 5000 eV , and densities with Wigner-Seitz radii r _ { s } = 1.0 and 0.5 .
The relaxation is slower than the LS result , even for temperatures in the keV range , but converges to agreement in the high- T limit .