[O V] in the Ultraviolet Spectra of Gaseous Nebulae
Feibelman, W. A.; Keenan, F. P.; Hyung, S.; Aller, L. H.; McKenna, F. C.; Berrington, K. A.; Fleming, J.; Hibbert, A.
United Kingdom, United States
Abstract
Theoretical O V electron-density-sensitive emission line ratios for R = I(2s2 1S0 - 2s2p 3P2)/I(2s2 1S0 - 2s2p 3P1) are presented. Inspection of Goddard High Resolution Spectrograph Hubble Space Telescope spectra of RR Tel reveals the presence of the [O V] 2s2 1S - 2s2p 3P2 line at 1213.80 Å, which is 4.62 +/- 0.12 Å away from the 2s2 1S - 2s2p 3P2 intercombination transition at 1218.42 Å, in good agreement with the theoretical prediction of Δλ = 4.54 Å. The resultant value of R = 0.82 +/- 0.11 implies a logarithmic electron density, log Ne, of 5.2 +/- 0.2 cm-3, in good agreement with that found from other ions with high electron temperature, such as Ne VI, which also provides support for the identification.