Dependence of normalized numbers of ions in the trap on storage time, t, for the D₃⁺ + NH₃ reaction. The measured data are indicated as triangles (D₃⁺), circles (NH₃D⁺), squares (m/z 20), diamonds (m/z 21) and pentagons (m/z 22). The signal at m/z 30 (hexagons) corresponds to N₂D⁺ formed from reaction with background N₂. The crosses (Σ) indicate the total number of ions. The lines indicate the fit kinetic model. The data were measured at T = 200 K, [NH₃] = 1.0 × 10¹⁰ cm⁻³, and [He] = 4.9 × 10¹³ cm⁻³.