Abstract
Three body recombination of atomic ions, where the third particle is the electron, so called collisional radiative recombination (CRR), is studied in the presented work. Theory predicts very strong inverse temperature dependence of CRR rate coefficient ($\alpha_{CRR}\approx T_e^{-4,5}$), making the process a dominant loss process of atomic ions in plasma at temperatures below 100 K.
Up to now there were no experimental studies of CRR in afterglow plasma at temperatures below 300 K. Presented is the flowing afterglow (Cryo-FALP) study of CRR in Ar+ dominated plasma at temperatures 77–300 K and electron densities up to $n_e\approx10^{10}cm^{-3}$.
The obtained ternary recombination rate coefficient at 77 K is $K_{CRR} = (1,0\pm 0,4) \times 10^{-17} cm^6s^{-1}$. The measured temperature dependence of $K_{CRR}$ is in good agreement with theoretical prediction.