Fine-structure electron-impact excitation of Ne+ and Ne2 + for low-temperature astrophysical plasmas

Collision strengths for the electron impact of the fine-structure levels within the ground term of Ne+ and Ne2 + are calculated using the Breit–Pauli r-matrix and the Dirac atomic r-matrix code (DARC) methods. Maxwellian-averaged effective collision strengths are presented for each ion. The application of the current calculations is to very low temperature astrophysical plasmas, down to 10 K, and thus we examine the sensitivity of the effective collision strengths to the resonance positions and underlying atomic structure. The use of the various theoretical methods allows us to place estimated uncertainties on the recommended effective collision strengths. Good agreement is found with previous r-matrix calculations at higher temperatures.