Inelastic Heavy Particle Collisions Involving the Crossing of Potential Energy Curves III: Charge Transfer from Negative Ions of Atomic Hydrogen to Protons

Cosmological Implications of the Uncertainty in H−Destruction Rate Coefficients

“…The lower value is said to be derived from the experimental results of Szucs et al (1984) and Peart et al (1985), which lie close to the theoretical cross section predictions of Bates & Lewis (1955). However, Figure 2 shows that the lower recommended value of Dalgarno & Lepp is a factor of %3 times smaller than that of Bates & Lewis (1955). Also, these experimental results were carried out for collision energies in excess of 5 eV, which is of little relevance for early universe chemistry.…”

“…The higher value is said to be based on the results of Moseley et al (1970), but as can be seen in Figure 2, lies a factor of %4 below their results. The lower value is said to be derived from the experimental results of Szucs et al (1984) and Peart et al (1985), which lie close to the theoretical cross section predictions of Bates & Lewis (1955). However, Figure 2 shows that the lower recommended value of Dalgarno & Lepp is a factor of %3 times smaller than that of Bates & Lewis (1955).…”

“…Using their cross section results and extrapolating below 0.1 eV, they produced an experimentally derived rate coefficient (Moseley et al 1970;Peterson et al 1971). Their experimental rate coefficient is a factor of %3 times larger than the LZ results of Bates & Lewis (1955). Dalgarno & McCray (1973) write that the rate coefficient for…”

Formation ofH3−by radiative association ofH2

“…We take the value of k ± ∼ 10 −7 cm 3 /s for the H − +H + →H+H reaction [36][37][38] at 10 meV. Therefore, we derive the equilibrium abundance of H − : n(H − ) = ζn(H 2 )f DA /(k ± n + ) ∼ 5 × 10 −7 cm −7 .…”

Отрицательные Ионы

“…Ρ e к о м б и н а[ц и я Сечение рекомбинации медленных положительных и отрицатель-ных ионов водорода было рассчитано в работе 177 . На рис 27. приве-дены кривые зависимости лога-рифма сечения рекомбинации (в единицах таг") от логарифма энер-гии столкновения для процессов: 180 .…”