Electron–Ion Temperature Ratio in Astrophysical Shocks

Collisionless shock waves in supernova remnants and the solar wind heat electrons less effectively than they ions, as is predicted by kinetic simulations. However, values of T$_e$/T$_p$ inferred from H alpha profiles remnant shocks behave differently a function Mach number or Alfv\'{e}n what measured Here we determine for using profiles, speeds proper motions, electron temperatures X-ray spectra. We also improve estimates sound speed used to numbers. find that determinations are robust discrepancies among shocks, computer-simulated remain. discuss some possible contributing factors, including precursors, turbulence varying preshock conditions.