Additional Series Lines in the Spectra of C II and N II

Abstract

Several of the strong lines of C II have been identified as combinations of the ${}_{}{}^4{}_{}{}^{}P$ term of the $s{p}^2$ configuration with the quartet terms observed by Fowler and Selwyn. This fixes the term values ${}_{}{}^4{}_{}{}^{}P_1^{}{}_{}{}^{}=206810.7\mathrm{}$, ${}_{}{}^4{}_{}{}^{}P_2^{}{}_{}{}^{}=206789.2\mathrm{}$, ${}_{}{}^4{}_{}{}^{}P_3^{}{}_{}{}^{}=206760.6\mathrm{}$. In N II, the term value of the ${}_{}{}^1{}_{}{}^{}S$ term of the $s^2{p}^2$ configuration, has been fixed at 206159, and of the ${}_{}{}^1{}_{}{}^{}P$ term of the $s{p}^3$ configuration at 72084 relative to the term values given by Fowler and Freeman. The ${}_{}{}^1{}_{}{}^{}S$ term combines with the ${}_{}{}^1{}_{}{}^{}D$ term of the same configuration to give the nebular line at 5754.8A. A large number of terms including those which Fowler and Freeman designated by "$a$" have been shown to belong to the quintet system. These have the following relative term values: $s{p}^{2}s$, ${}_{}{}^5{}_{}{}^{}P_1^{}{}_{}{}^{}=90000\mathrm{}$, ${}_{}{}^5{}_{}{}^{}P_2^{}{}_{}{}^{}=89943.8\mathrm{}$, ${}_{}{}^5{}_{}{}^{}P_3^{}{}_{}{}^{}=89873.1\mathrm{}$; $s{p}^2·p$, ${}_{}{}^5{}_{}{}^{}S=65759.0\mathrm{}$, ${}_{}{}^5{}_{}{}^{}P_1^{}{}_{}{}^{}=69994.5\mathrm{}$, ${}_{}{}^5{}_{}{}^{}P_2^{}{}_{}{}^{}=69970.7\mathrm{}$, ${}_{}{}^5{}_{}{}^{}P_3^{}{}_{}{}^{}=69926.9\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_0^{}{}_{}{}^{}=71955.0\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_1^{}{}_{}{}^{}=71939.8\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_2^{}{}_{}{}^{}=71909.6\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_3^{}{}_{}{}^{}=71866.5\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_4^{}{}_{}{}^{}=71812.6\mathrm{}$; $s{p}^2·d$, ${}_{}{}^5{}_{}{}^{}D_1^{}{}_{}{}^{}=50658.5\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_2^{}{}_{}{}^{}=50650.6\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_3^{}{}_{}{}^{}=50639.3\mathrm{}$, ${}_{}{}^5{}_{}{}^{}D_4^{}{}_{}{}^{}=50624.9\mathrm{}$, ${}_{}{}^5{}_{}{}^{}F_2^{}{}_{}{}^{}=52611.4\mathrm{}$, ${}_{}{}^5{}_{}{}^{}F_3^{}{}_{}{}^{}=52585.3\mathrm{}$, ${}_{}{}^5{}_{}{}^{}F_4^{}{}_{}{}^{}=52551.6\mathrm{}$, ${}_{}{}^5{}_{}{}^{}F_5^{}{}_{}{}^{}=52511.1\mathrm{}$; $s{p}^3$, ${}_{}{}^5{}_{}{}^{}S=248812\mathrm{}(?)\mathrm{}$.