No CrossRef data available.
Published online by Cambridge University Press: 12 April 2016
In our paper (Ch. Fehrenbach and C.C. Huang, 1981) we have described the details of our spectroscopic observations of CI Cyg in 1980. In that year, the star showed a fair presence of bright forbidden lines of [FeV ]and very strong emission lines of high and low excitation, including forbidden [0 III ] , [Ne III], [Fe II ] and [S II] and permitted 0 III, N III as well as He I and Fe II … etc … The He II 4686 A was very strong. The Balmer lines were the strongest emission features in the spectrum and Hα and Hβ were double. There were two groups of velocities in 1980, one was positive for forbidden lines and the other was negative for the permitted lines. The displacements of Balmer lines showed a regression.