Ionization efficiencies, ﹩\beta \left(v\right)﹩, resulting from collisions with CO₂ molecules in the upper atmosphere of Venus, as a function of the entry velocity for the main meteoric atoms (panel (a)) and the most relevant oxides (panel (b)), predicted by CABMOD. The vertical dashed lines illustrate the values of the average input velocities for each meteoroid population (see Figure 3(b)).