Effective collision strengths for O II

Accurate electron collisional excitation strengths Ω, from 11 state R-matrix calculations performed in LSπ coupling, are convoluted with a Maxwellian velocity distribution to obtain effective collision strengths γ for a range of temperatures 5×10 3 K to 10 6 K for electron excitation of singly ionized atomic oxygen. This work considers electron collisional excitation of the O II ion from the 1s 2 2s 2 2p 3 ( 4 S 0 ) to the 1s 2 2s 2 2p 3 ( 2 D 0 , 2 P 0 ) and to the higher lying 1s 2 2s2p 4 ( 4 P e ) and 1s 2 2s 2 2p 2 3s ( 4 P e ) states