Three-body ion–molecule processes

Abstract

The neutron emission spectrum from d + t → α + n reactions has been measured as a means to study the plasma response to radio frequency (RF) power coupled to hydrogen and deuteron minority components (through fundamental and second harmonic, respectively) in a tritium discharge at JET. The spectrum was measured with the magnetic proton recoil spectrometer and was analysed in terms of two spectral components due to thermal (TH) and high-energy (HE) deuterons interacting with the bulk ion population of thermal tritons. The results were used to derive information on the deuteron population in terms of temperatures (T TH and T HE ) as well as corresponding particle and kinetic energy densities of the plasma; the bulk ion temperature (T i = T TH ) was determined both before (with Ohmic heating only) and during the RF pulse. Similar information on protons was derived from other measurements in order to estimate the different RF effects on protons and deuterons. This paper illustrates qualitatively the type of empirical ion kinetic information that can be obtained from neutron emission spectroscopy; the data serves as a basis for comparison with results of predictive and interpretative models on RF effects in plasmas.

Comparison of classical and quantal calculations of helium three-body recombination

“…To explore other theoretical studies of recombination or its time-reverse process (collision-induced dissociation, CID) and the validity of various approximation methods, see also Refs. 12,14,[17][18][19][20][21][22][23][24] The present paper implements a general method to study classical collisions in n-dimensions. This method utilizes classical trajectory calculations to calculate the three-body recombination rate (TBRR) for helium atoms in a framework related to the pioneering formulation of F. T. Smith.…”

10 Gas phase organic ion–molecule reaction chemistry

“…In recent years, numerous reviews have been presented on topics related to gas phase organic ion chemistry including the following: organic ions, 1 electrophilic reactions with aromatic substrates, 2,3 nucleophilic displacement reactions, 4 radical anions, 5 molecular cluster reactions, 6 fullerene carbon clusters, 7,8 sulfur- 9 and silicon- 10,11 containing ions, gas phase ion^atom reactions, 12 atmospheric ion chemistry, 13 interstellar and circumstellar chemistry, 14 the analytical applications of ion^molecule reactions, 15^17 multiply charged ions, 18,19 anhydrous protein ions, 20 and three body ion^molecule reactions. 21 These reviews provide a foundation for the material presented here.…”