Density-dependent excitation rate for the2p2P3dielectronic satellite line in a laser-produced carbon plasma

The relative intensities of the $2l2l^{\prime }$ dielectronic satellite transitions of C v have been measured as functions of electron density and temperature in a laser-produced plasma. The relative intensity of the $2p^2{}_{}{}^3{}_{}{}^{}P-1s2p{}_{}{}^3{}_{}{}^{}P$ transition is observed to vary with electron density in the range 8×${10}^{19}$ to 2×${10}^{20}$ ${\mathrm{cm}}^{-3\mathrm{}}$. In this density range, the satellite line intensities are consistent with electron collisional population of the $2p^2{}_{}{}^3{}_{}{}^{}P$ level from the $2s2p{}_{}{}^3{}_{}{}^{}P$ level, both doubly excited. The measured rate coefficient for this collisional transition, inferred from the density dependence of the $2p^2{}_{}{}^3{}_{}{}^{}P$ spectral radiation, agrees with recently calculated values. In contrast to previous higher-$Z$ experiments, electron collisional population of the $2p^2{}_{}{}^3{}_{}{}^{}P$ level from the singly excited $1s2p{}_{}{}^3{}_{}{}^{}P$ level is found to be unimportant in this experiment.