ATOMIC DATA FROM THE IRON PROJECT .2. EFFECTIVE COLLISION STRENGTHS FOR INFRARED TRANSITIONS IN CARBON-LIKE IONS

We present new calculations of cross-sections for the electron impact excitation of carbon-like ions from N II to S XI, paying particular at tention to the infrared transitions between the 2p(2) P-3 J = 0,1,2 gr ound state fine-structure levels. We also give rate coefficients, assu ming a Maxwellian electron velocity distribution, in the form of effec tive collision strengths for these transitions up to an electron tempe rature of 10(5) K. We also give results for transitions involving the other 2p(2) terms (D-1 and S-1) as well as the 2s2p(3) (S-5) term. The present results are in excellent agreement with a number of similar c alulations available in the literature but are more comprehensive in s cope.