The time evolution of the TOF spectrum of ³He^{2 +} ions at the lowest CH₄ pressure used

Figure 2. The time evolution of the TOF spectrum of ³He^{2 +} ions at the lowest CH₄ pressure used. Only ³He^{2 +}, m/q = 1.5, and some m/q = 2 are stored. No ion with m/q > 2 is stored. The FWHM of ³He^{2 +} is 26.1 ± 2.9 ns, 26.8 ± 3.3 ns, 25.8 ± 3.1 ns, 25.0 ± 3.0 ns and 24.8 ± 3.8 ns for the recorded times of 10, 70, 130, 190 and 250 ms, respectively. Here, t = 10 ms corresponds to 50 ms after the cathode activation, t = 70 ms corresponds to 110 ms after cathode activation, t = 130 ms corresponds to 170 ms and so on.

Abstract

We report our measured values for the sum of single and double charge transfer rate coefficients between ³He^{2 +} and H₂, CH₄, N₂ and CO. Our values are 2.4 ± 0.2 × 10⁻⁹ cm³ s⁻¹ for H₂, 6.3 ± 0.9 × 10⁻⁹ cm³ s⁻¹ for CH₄, 4.0 ± 0.3 × 10⁻⁹ cm³ s⁻¹ for N₂ and 4.7 ± 0.4 × 10⁻⁹ cm³ s⁻¹ for CO. The values are obtained at equivalent temperatures of 1200–2400 K.