Electron capture in C6++ H collisions in Debye plasmas

The electron capture in C 6+ –H collisions taking place in a weakly coupled plasma is studied by the two-centre atomic orbital close-coupling method. The interaction between charged particles is represented by the Debye–Hückel potential, appropriate for weakly coupled (Debye) plasmas. The adopted two-centre expansion basis contains all the states with n ⩽ 8 centred on C 6+ and all the states with n ⩽ 2 centred on H + . The coupled channel calculations have been performed in the 0.5–100 keV/u energy range in which the results with the adopted basis are convergent. It is shown that the electron capture dynamics in Debye plasmas is strongly affected by the plasma screening of charged particle interactions mainly due to the reduction of electron binding energy and the number of reaction channels when the plasma screening increases. These effects are illustrated on the state-selective electron capture cross sections for a number of representative values of the interaction screening parameter and on the properties of a number of charge exchange spectral lines.