CROSS SECTIONS AND RATE COEFFICIENTS FOR EXCITATION OF THE 1s22s2p3PoJ→ 1s22s2p3PoJ′FINE-STRUCTURE TRANSITIONS IN BERYLLIUM-LIKE IONS BY HEAVY PARTICLE IMPACT

Abstract

Cross sections for excitation of the 1s22s2p3PoJ→ 1s22s2p3PoJ′fine-structure transitions in beryllium-like ions by proton, deuteron, triton, and α-particle impact have been calculated using a close-coupled impact-parameter method. This technique includes the effects of dipole coupling to the nearby triplet 2p2, 2s3s, and 2s3dconfigurations by means of a polarization potential. We consider the ions C III, N IV, O V, Ne VII, Mg IX, Al X, Si XI, S XIII, Ar XV, Ca XVII, Ti XIX, Cr XXI, Fe XXIII, and Ni XXV. Excitation rate coefficients have also been calculated from the cross sections for a range of temperatures.