Abstract
UV spectra of the noncoronal single K supergiant λ Vel and of the single M giant γ Cru obtained with IUE and the Hubble Space Telescope at various epochs indicate that the profiles of many lines formed in the wind exhibit striking alterations in shape with time. We parameterize the wind profiles in terms of an empirical optical depth τemp by reflecting the red wing about line center and comparing the reflected intensity with that of the blue wing. In the λ Vel wind the terminal velocity v∞ was found to be close to 40 km s-1 in 1978, 1982, and 1994, but was at least 20 km s-1 greater in 1990. The faster wind in 1990 also had a total optical depth that was a factor of 2-6 times greater than at the other epochs.
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