Recent increase of the activity of the symbiotic star CH Cygni

Extract

CH Cyg has exhibited a great deal of activity in the recent times. We obtained two spectra with dispersion of 9 A/mm with the 2 m telescope of the Ondrejov Observatory on the nights of July 4/5 and August 6/7, 1981. The differences between these spectra are conspicuous. The description of the spectral changes during this period follows:

The Balmer lines became broader, the R wing of the early Balmer shell lines being partly suppressed by absorption. The inverse P Cygni profiles became apparent from H₈ to H₃₀.