Recombination coefficients for CII lines^*

¹ Department of Physics, Montana State University, Bozeman, MT 59717-3840, U.S.A.
² Department of Physics and Astronomy, University College London, Gower St., London, WC1E 6BT, UK e-mail: rk@star.ucl.ac.uk, pjs@star.ucl.ac.uk

Send offprint request to: P.J. Storey

Received: 20 July 1999
Accepted: 4 October 1999

Abstract

Effective recombination coefficients are given for CII transitions between doublet states. The calculations are carried out in the temperature range and for an electron density of 10⁴ cm^-3. The effects of electron collisions on the excited states are included. The necessary bound-bound and bound-free radiative data are obtained from a new R-matrix calculation in which photoionization resonances are fully delineated, thereby accurately incorporating the effects of both radiative and dielectronic recombination. The R-matrix calculation includes all bound states with principal quantum number and total orbital angular momentum . The effect of moving the resonance features to their experimentally determined positions is also investigated and found to be important at low temperatures.