COMMISSIONS 27 AND 42 OF THE IAU
          INFORMATION BULLETIN ON VARIABLE STARS
                       Number 3865

                                           Konkoly Observatory
                                           Budapest
                                           2 April 1993

                                           HU ISSN 0374 - 0676


              PHOTOELECTRIC BVR OBSERVATIONS
              OF THE ECLIPSING VARIABLE HY Tau


On the identification chart of the Cepheid EF Tau (Zessevich, Kazanasmas, 1971)
the suspected variable star CSV 669 is also indicated.  We have observed it
together with the Cepheid photoelectrically in the BVR system.  The 60-cm
reflector of the Mt. Maidanak Observatory of the Tashkent Astronomical
Institute was used and 45 observations (Table 1) were obtained.  The estimated
error of the individual data is about +-.015 mag.  It turned out later, that
CSV 669 is identical with the eclipsing variable HY Tau (Kholopov et al., 1987)
the elements of which are as follows:

        Min=JD hel 2431530.306+3.01682d x E          (1)

HY Tau has not been observed photoelectrically before.  The elements (1) were
used in phase calculations for Table I and Figure 1.  Light curves in Figure 1
show that the elements need improvement.

                     Table 1

   JD Hel       Phase     V        B-V     V-R
   2400000+
   47083.4386   0.473   11.728    0.780   0.581
   47084.3846   0.786   11.717    0.807   0.570
   47085.4285   0.132   12.038    1.081   0.686
   47087.4265   0.795   11.656    0.815   0.583
   47088.4205   0.124   12.026    1.059   0.676
   47409.4876   0.550   11.744    0.848   0.863
   47410.4848   0.880   11.771    0.812   0.875
   47411.4915   0.214   11.768    0.815   0.918
   47413.4857   0.875   11.800    0.778   0.935
   47415.4942   0.541   11.735    0.827   -
   47416.4916   0.872   11.739    0.820   0.873
   47417.4841   0.201   11.796    0.845   0.885
   47418.4866   0.533   11.699    0.854   0.861
   47419.4894   0.865   11.658    0.866   0.836
   47420.4896   0.197   11.796    0.876   0.889
   47421.4913   0.529   11.707    0.859   0.871
   47422.4902   0.860   11.719    0.790   0.873
   47424.4841   0.521   11.683    0.815   0.870
   47425.4817   0.852   11.685    0.861   0.836
   47427.4865   0.516   11.684    0.892   0.859
   47428.4766   0.844   11.787    0.827   0.956
   47430.4882   0.511   11.697    0.838   0.863
   47431.4903   0.843   11.724    0.842   0.827
   47432.4864   0.173   11.886    0.973   0.927
   47433.4651   0.498   11.696    0.888   0.869
   47760.4865   0.897   11.730    0.846   -
   47768.4820   0.548   11.688    0.874   -
   47770.4633   0.204   11.741    0.860   0.965
   47771.4696   0.538   11.690    0.871   0.882
   47772.4744   0.871   11.715    0.840   0.898
   47773.4686   0.200   11.778    0.854   0.904
   47774.4837   0.537   11.698    0.867   -
   47775.4762   0.866   11.678    0.847   0.929
   47776.4659   0.194   11.823    0.885   0.912
   48505.4249   0.826   11.740    0.850   0.895
   48509.4427   0.157   12.086    1.066   1.033
   48510.4332   0.486   11.744    0.851   0.868
   48511.4073   0.809   11.743    0.840   0.871
   48513.4148   0.474   11.725    0.845   0.870
   48516.4181   0.470   11.736    0.859   0.889
   48517.4151   0.800   11.708    0.864   0.876
   48518.4142   0.131   11.995    1.068   0.961
   48520.4193   0.796   11.753    0.856   0.871
   48521.4301   0.131   12.007    1.067   0.974
   48523.4081   0.787   11.748    0.862   0.877


                            [FIGURE 1]


It is pleasure to thank Dr.  V.  S.  Shevchenko for the observing time
necessary to carry out the present observations.



L. N. BERDNIKOV
Sternberg State Astronomical
Institute, Moscow, Russia
University of Saratov,
Saratov, Russia

References:

Kholopov P. N. et al., 1987 General Catalogue of Variable Stars, Vol III.,
    Moscow, "Nauka" [BIBCODE 1987gcvs.book.....K ]
Zessevich, V. P., Kazanasmas, M. S., 1971, Atlas of Identification Charts of
    Variable Stars, Moscow, "Nauka"