COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 2435

                                     Konkoly Observatory
                                     Budapest
                                     25 November 1983

                                     HU ISSN 0374-0676


       ON THE VARIABILITY OF THE STAR SAO 072799



   The star SAO 072799 (BD+37d4713) has been reported in
I.B.V.S. No.1885 to be an eclipsing variable with a period
4.2150951d. The variability of this star was noticed during
photographic observations of the system SW Lac by Frank (1980).
A request for a confirmation of the variability of SAO 072799
led us to observe the system photoelectrically.

   The photoelectric observations were made on August 29-31
and September 1-3, 1981, as well as on September 16-19, 1982.
The observations were made at Kryonerion Astronomical Station,
Greece, with a 48-inch Cassegrain reflector and a two beam
multi-mode photometer (Goudis and Meaburn,1973). The two
intermediate pass-band filters used were selected to be in
close accordance with the standard U,B,V colour system. As
comparison star we used SAO 072816 for the period of August-
September 1981 and SAO 072787 for the period of September 1982.

  The observations made during those periods are given in
Figures 1 and 2, respectively. From an inspection  of Figure 1
it is obvious that a light minimum occurs around phase 0.5.
The ascending branch of that minimum is clearly  shown. On the
other hand, Figure 2 shows another minimum  at phase 0.18.
Here the descending branch and a small part of the ascending
one can easily be seen. Moreover, there is no indication in
both Figures that another minimum exists at  any other phase

   From the observations given in Figures 1 and 2 we can
conclude that the star SAO 072299 is certainly  variable, but
it is difficult to define the type and the period of its
variability. Therefore, more extensive observations are needed
for a better understanding of this new discovered variable
star.

                       [FIGURE 1]


       Figures 1-2   B and V light curves of SAO 072799




            P. G. NIARCHOS
            Department of Astronomy
            University of Athens
            Panepistimiopolis, Athens 621
            Greece





References:
Frank, P.: 1980, I.B.V.S. No. 1885
Goudis, C. and Meaburn, J.: 1973, Astrophys. Space Sci., 20, 149 [BIBCODE 1973Ap&SS..20..149G ]