Dielectronic recombination of Ne-like tungsten

Relativistic calculations of the dielectronic recombination (DR) cross section and rate coefficient for Ne-like tungsten (W⁶⁴⁺) in the ground state 2s²2p⁶ are performed. The DR contributions of the most important Na-like doubly excited configuration complexes, namely, (2s2p)⁷3ln^′l^′ (n^′=3–13) and (2s2p)⁷4l4l^′, are calculated by level-by-level computations. Collisional transitions following the initial electron capture are neglected. The total DR cross section is presented in the form of 5-eV-wide peaks for the purpose of revealing the detailed atomic level structure, and in the form of 50-eV-wide peaks for the purpose of comparison with planned electron-beam experiments. The (2s2p)⁷3l3l^′ complex is found to provide the dominant DR channel. The sum of the DR contributions of the (2s2p)⁷3ln^′l^′ configurations with n^′>13, evaluated by applying the complex-by-complex n^′-3 extrapolation method, is found to represent at most 3% of the total DR rate coefficient. The DR contribution of (2s2p)⁷3ln^′l^′ configurations with l^′>5 is found to be negligible (about 0.1%). The total DR rate coefficient is fitted to a convenient analytical expression which reproduces the original data with an accuracy of about 2% or better within a very wide electron temperature range.