Branching ratios of electron-ion recombination reactions of astrophysical interest

Project leader

Funding source

EU Fifth Framework Programme - Improving Human Potential

Project Details

Start date: 01/12/2002
End date: 30/11/2004
Funding: 150304 EUR


Electron-ion recombination reactions are particularly important in laser plasmas, combustion flames and the interstellar medium (ISM). The research project focuses on assessing the branching ratios of the astrophysically interesting electron recombination processes of HCO^+, HN_2^+, HCO_2^+, HCCCN^+ , C_2H_4^+, CH_3CCH^+ , C_3H_3^+(propargylium and cyclopropenium isomers) and HCCCCH^+. Whereas reaction rates of some of these processes are well known, little information is available about their ranching ratios, which are crucial for model calculations of interstellar clouds and planetary ionospheres. The CRYRING storage ring located in the Manne Siegbahn Laboratory at Stockholm University, Sweden is one of only two facilities world-wide capable of performing the proposed experiments. It allows to perform experiments at the very low collision energies encountered in dark interstellar clouds. The ions, generated in a plasma discharge source are stored in the ring and merged with the electrons. The neutral recombination products will be detected with a surface barrier detector and the transmission grid method will be used to assess the branching ratios. If successful, the proposed research will mean a great step forward in understanding of interstellar and ionospheric recombination reactions and yield reliable data that will considerably improve the quality of astrophysical model calculations.

Last updated on 2017-24-03 at 12:49