COMMISSION 27 OF THE I. A. U.
          INFORMATION BULLETIN ON VARIABLE STARS
                      Number 2590

                                           Konkoly Observatory
                                           Budapest
                                           20 September 1984

                                           HU ISSN 0374-0676


                  UBV PHOTOMETRY FOR BD+37d 2356

  The variable star BD+37d 2356, classified as W UMa type variable star by
Zhukov (1982), was observed in March and  May 1984 using UBV photometer
attached to the 91 cm reflector at McDonald Observatory. Same comparison
star (HD 113 730= BD+37d 2360) with Zhukov's was used and about 300 observations
in U, B and V bands were taken for the program star.
  Six moments of minima were determined, their JD(hel) are as follows:
    2445 769.7314 (II),    2445 770.6919 (I),      2445 770.8840 (II),
    2445 773.7655 (I),     2445 773.9575 (II),     2445 841.7710 (I)
The new epoch of the primary minimum and the orbital period are:

    JD(hel) = 2445 841.7710 (+-0.0003) +0.3842105d (+-0.0000001)E

The new period is a little longer than 0.38416d given by Zhukov.
  The light curve of V magnitude is shown in Figure 1. The eclipse depths
at primary and secondary minima are almost equal. Vmax=10.228m (+-0.008m),
Vmin=10.689m (+-0.008m). The colour indexes, shown in Figure 2 and Figure 3,


                              [FIGURE 1]
                              [FIGURE 2]
                              [FIGURE 3]


vary lightly with phase. The average colour indexes are:

          _____                  _____ 
          (B-V) = 0.578m    ,    (U-B) = 0.045m   .


                      LIU XUEFU and TAN HUISONG
                      McDonald Observatory
                      The University of Texas
                      (visiting scholars from China)

Reference:

Zhukov, G.V. 1982, Inf. Bull. Var. Stars, No. 2191.