COMMISSION 27 OF THE I. A. U.
       INFORMATION BULLETIN ON VARIABLE STARS
                   Number 1701

                               Konkoly Observatory
                               Budapest
                               1979 November 5


      PHOTOELECTRIC MINIMA OF AW UMa AND W UMa


Photoelectric observations of eclipsing systems AW UMa and W UMa were made on
twelve nights from February through April 1979 using the 38 cm. reflector at
the Villanova University Observatory. Complete light curves were obtained for
both stars. A pair of wide and narrow interference filters centered on the
H_alpha feature were used, their characteristics are: H_alpha_w (max= 6595; HW
FH=270 A), H_alpha_n (max=6569; HWFH=36 A). A further description of the
equipment and system is given by Guinan and Tomczyk (1979).

The usual sky-comp.-var.-comp.-sky observing sequence was used in the
collection of the data. The tracing paper method (Szafraniec, 1948) was used
to determine the time of minimum light for data collected through the H_alpha_w
filter. The ephemeris for AW UMa was JD Hel. 2438044.7815+0.4387318 (Kalish,
1965) and for W UMa it was JD Hel. 2433282.6828+0.3336379 (Rigterink, 1972).

Star     Time of Min. (JD Hel. )     O-C      Observer

AW UMa   2443945.7220              -0.0022    McNamara
         2443948.7927              -0.0026    Stoke

W UMa    2443924.7296              -0.0021    Hart
         2443949.7516              -0.0029    King
         2443941.7443              -0.0029    Seaman


M. KEVIN HART
KENNETH KING
BRIAN R. McNAMARA
ROBERT L. SEAMAN
JOHN STOKE
Department of Astronomy
Villanova University
Villanova, Pennsylvania 19085

References:

Guinan, E.F., and Tomczyk, S., 1979, I.B.V.S., No. 1623.
Kalish, M.S., 1965, Publ. Astron. Soc. Pacific., 77, 36. [BIBCODE 1965PASP...77...36K ]
Rigterink, P.V., 1972, Astron. J., 77, 230. [BIBCODE 1972AJ.....77..230R ]
Szafraniec, R., 1948, Acta Astron., 4, 81.