Storage-ring measurement and multiconfiguration Dirac-Fock calculations

The electron-ion recombination rate coefficient for Si IV forming Si III was measured at the heavyion storage-ring TSR. The experimental electron-ion collision energy range of 0–186 eV encompassed the 2p nl n′l′ dielectronic recombination (DR) resonances associated with 3s→ nl core excitations, 2s 2p 3s nl n′l′ resonances associated with 2s → nl (n = 3, 4) core excitations, and 2p 3s nl n′l′ resonances associated with 2p → nl (n = 3, . . . ,∞) core excitations. The experimental DR results are compared with theoretical calculations using the multiconfiguration Dirac-Fock (MCDF) method for DR via the 3s→ 3p n′l′ and 3s→ 3dn′l′ (both n′ = 3, . . . , 6) and 2p 3s 3l n′l′ (n′ = 3, 4) capture channels. Finally, the experimental and theoretical plasma DR rate coefficients for Si IV forming Si III are derived and compared with previously available results.