NEW EXCITATION RATES AND LINE RATIOS FOR [FE-II]

Improved rate coefficients and line ratios are reported for the diagnostics of IR spectra of Fe II based on extensive new calculations of collision strengths using a 38 state close-coupling expansion. Results presented pertain to all 16 lowest levels and 120 transitions. The present rates are generally higher from previous works by significant factors, predicting brighter IR line flux for a given iron abundance, and are likely to affect the derived densities, temperatures, and abundances in a wide range of IR sources.