Solar Wind Ion Composition

Abstract

In addition to the two ion species previously observed in the solar wind, $^{1}\mathrm{H}^{+}$ and $^{4}\mathrm{He}^{++}$, Vela satellite measurements reveal the presence of ions of $^{3}\mathrm{He}^{++}$, $^{4}\mathrm{He}^{+}$, various ion species of $^{16}\mathrm{O}$, and other unidentified heavy ions. From the number ratios of the ${\mathrm{O}}^{+7}$, ${\mathrm{O}}^{+6}$, and ${\mathrm{O}}^{+5}$ ion species measured near earth, it may be inferred that the ionization state ratios are established deep within the solar corona at million-degree temperatures.