U Cephei (V = 6.8–9.0, P = 2.493 d) is an eclipsing binary consisting of a B7V primary and a G8III-IV secondary component. This binary is one of the semidetached Algol systems showing soft X-ray emission which is probably associated with a hot corona surrounding the secondary component (White and Marshall 1983).We made spectroscopic observations of U Cep with the coudé image-tube spectrograph of the 1.9-m telescope at Okayama Astrophysical Observatory on October 14, 1986. We obtained four spectrograms with a dispersion of 16 Å mm-1 covering λ λ3700—4300 Å during the primary eclipse. The first two exposures were made in a total eclipse, while the last two were slightly after the third contact. The CaII H and K emission lines appear clearly in all the spectrograms. Figure 1 represents an intensity tracing of one of these spectrograms.
Call H and K Emission in the Secondary Component of U Cephei
