COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1540

                                 Konkoly Observatory
                                 Budapest
                                 1979 January 31




   HD 61429, A POSSIBLE NEW W UMa ECLIPSING BINARY SYSTEM


   Photoelectric observations of HD 61429 have been obtained with the
Bochum University 61 cm telescope, at La Silla, Chile. Used as a comparison
for HD 63462 and HD 62623 it turned out to be variable itself.
    Of spectral type B9, HD 61429 is a visual double stars (ADS 6246)
with a companion of similar spectral type and magnitude at 0.1 arcseconds
distance. Radial velocity variations of the order of 70 km/sec have been
reported in the Publ. Lick Obs. (1928). They might be due to the presence
of a third, unseen companion.
   Between January 3 and January 31, 1977 observations relative to
HD 60863 were made on 23 nights. Reduction procedures were the same as those
described by Stift (1978). The combination of the observations of each
night yields an internal precision of ~0.002m. The observations were
analyzed with the help of a period search program using a five component
Fourier least squares fit. The final period retained of 2.57895 days yields
by far the smallest scatter and the resulting light curve in V is shown in
Fig. 1. Colour variations are marginal. Despite the imperfect phase
coverage a W UMa or beta Lyr type eclipsing binary nature of HD 61429 appears
very likely. This would account for the observed variations in radial
velocity; most unfortunately the RV data are too few and of low precision
to derive a curve of RV variations.
     We shall mention two alternative periods which give considerable
scatter but cannot be ruled out completely. A period of 0.56371 days
suggests non-radial pulsations of a star related to beta Cep variable 
(Smith, 1977).

                             [FIGURE 1]

   Figure 1: Light curve of HD 61429 relative to HD 60863. The phases are
   given by Phi = (J.D. - 2443100) 2.57895 ^-1 .

Photometry in the Maitzen system (Maitzen, private communication) excludes
an Ap-Si star. A period of 4.488 days is neither convincing nor would
HD 61429 fit into any known variable class.
     As so often we have to call on more observations, photoelectric and
spectroscopic, for further clarification.




                            M.J. STIFT
                            Institut fur Astronomie
                            Universitats-Sternwarte
                            Wien



References:

Smith, M.A.: 1977, Ap.J. 215, 574 [BIBCODE 1977ApJ...215..574S ]
Stift, M.J.: Astron.Astrophys.Suppl. 32, 343 [BIBCODE 1978A&AS...32..343S ]