COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1732

                                     Konkoly Observatory
                                     Budapest
                                     1980 January 24


               NEW LIGHT CURVES OF RS CVn


The eclipsing binary RS CVn has been observed at the Ege University Observatory
from March 25 to August 3, 1979. The observations in B and V were made with
the 48 cm Cassegrain telescope equipped with unrefrigerated EMI 9781 A
photomultiplier. The filters B and V are approximately in the standard UBV
system. BD+36d2347 as proposed by Hall (1976) was used as comparison star.
The phases of individual observations have been computed with the following
light elements

Min I = JD Hel. 2439834.471+4.79781d*E.

The light curves obtained in B and V colours are shown in Figures 1 and 2.

                          [FIGURE 1]

             Fig. 1.  B light curve of RS CVn.

                          [FIGURE 2]

             Fig. 2.  V light curve of RS CVn.

The wave-like distortion outside the minima is clearly seen. The amplitude of
the wave is about 0.09m in blue and 0.14m in yellow light. The maximum and
minimum of the wave fall approximately at the phases 0.22 and 0.72,
respectively. The amplitude of the wave and the phase of the minimum of the
wave agree well with the values computed from the equations given by Hall
(1972).

The observations will be carried on in the next observing seasons.


S. EVREN, Z. TUNCA, O. TUMER, A.Y. ERTAN
C. IBANOGLU and M. KURUTAC
Ege University Observatory
Bornova-Izmir, Turkey

References:

Hall, D.S., 1972, Pub. A.S.P. 84, 323 [BIBCODE 1972PASP...84..323H ]
Hall, D.S., 1976, I.A.U. Comm. 42, Circ. 2