10.6084/m9.figshare.1012751.v1 C Kyriakides C Kyriakides B S Clarke B S Clarke V H S Kwong V H S Kwong The <sup>3</sup>He<sup>2 +</sup> ion population decay under different CH<sub>4</sub> pressures (a) and the corresponding decay rates plotted against CH<sub>4</sub> number densities (b) IOP Publishing 2013 cm CH 4 number densities CH 4 pressures co equivalent temperatures N 2 charge transfer rate coefficients ion population decay decay rates Atomic Physics Molecular Physics 2013-09-06 00:00:00 Figure https://iop.figshare.com/articles/figure/_The_sup_3_sup_He_sup_2_sup_ion_population_decay_under_different_CH_sub_4_sub_pressures_a_and_the_co/1012751 <p><strong>Figure 3.</strong> The <sup>3</sup>He<sup>2 +</sup> ion population decay under different CH<sub>4</sub> pressures (a) and the corresponding decay rates plotted against CH<sub>4</sub> number densities (b).</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>