Total cross-sections have been measured for the associative ionisation of C++O-, N++O- and O++O- by means of a merged-beam set-up operating with keV beams. These original measurements might be relevant to the understanding of some astrophysical objects or laboratory-made plasmas (flames and etching plasmas). The magnitude of these cross-sections is particularly large whatever the associating system, as these are in the range of 1210-14 cm2 at thermal energies. Their behaviour as a function of energy significantly differs from one system to another, and is characterised by the Wigner law at low energy, and a rapid fall-off at higher energy due to competition with non-associative ionisation processes.
doi : 10.1140/epjd/e20020090
Voir en ligne : Eur. Phys. J. D, 19, 315-325, (2002)