The time evolution of the TOF spectrum of <sup>3</sup>He<sup>2 +</sup> ions at the lowest CH<sub>4</sub> pressure used

2013-09-06T00:00:00Z (GMT) by C Kyriakides B S Clarke V H S Kwong
<p><strong>Figure 2.</strong> The time evolution of the TOF spectrum of <sup>3</sup>He<sup>2 +</sup> ions at the lowest CH<sub>4</sub> pressure used. Only <sup>3</sup>He<sup>2 +</sup>, <em>m</em>/<em>q</em> = 1.5, and some <em>m</em>/<em>q</em> = 2 are stored. No ion with <em>m</em>/<em>q</em> > 2 is stored. The FWHM of <sup>3</sup>He<sup>2 +</sup> 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, <em>t</em> = 10 ms corresponds to 50 ms after the cathode activation, <em>t</em> = 70 ms corresponds to 110 ms after cathode activation, <em>t</em> = 130 ms corresponds to 170 ms and so on.</p> <p><strong>Abstract</strong></p> <p>We report our measured values for the sum of single and double charge transfer rate coefficients between <sup>3</sup>He<sup>2 +</sup> and H<sub>2</sub>, CH<sub>4</sub>, N<sub>2</sub> and CO. Our values are 2.4 ± 0.2 <b>×</b> 10<sup>−9</sup> cm<sup>3</sup> s<sup>−1</sup> for H<sub>2</sub>, 6.3 ± 0.9 <b>×</b> 10<sup>−9</sup> cm<sup>3</sup> s<sup>−1</sup> for CH<sub>4</sub>, 4.0 ± 0.3 <b>×</b> 10<sup>−9</sup> cm<sup>3</sup> s<sup>−1</sup> for N<sub>2</sub> and 4.7 ± 0.4 <b>×</b> 10<sup>−9</sup> cm<sup>3</sup> s<sup>−1</sup> for CO. The values are obtained at equivalent temperatures of 1200–2400 K.</p>