On the nature of the 125 day cepheid V810 CEN (=HR 4511) : IUE spectra.
Pakull, M.; van Genderen, A. M.; Heck, A.; Lub, J.; Eichendorf, W.; Isserstedt, J.; Reipurth, B.
Germany, Netherlands, Denmark
Abstract
Low and high resolution IUE spectra of the possible extremely long-period, low-amplitude classical Cepheid V 810 Cen (equals HR 4511), are analyzed to determine the effects of its hot blue companion on the observed optical light - and radial velocity - curves. From these spectra we conclude that the early B - type companion is hardly detectable in the optical, and furthermore, that the observed amplitudes and amplitude ratios cannot be explained by a binary system. The observed optical features are clearly due to V 810 Cen itself.