COMMISSION 27 AND 42 OF THE IAU
                   INFORMATION BULLETIN ON VARIABLE STARS
                               Number 3837

                                                         Konkoly Observatory
                                                         Budapest
                                                         4 February 1993

                                                         HU ISSN 0374 - 0676


                 A NEW BRIGHT ECLIPSING VARIABLE IN CEPHEUS

                           (BAV-Mitteilung Nr. 64)

Variations in the light of HD 208106 (BD+61d2209, SAO 019685) were first
recorded photoelectrically by Sarg and Wramdemark (1970). As NSV 13911 the
star was included in the "New Catalogue of Suspected Variable Stars". The type
of variability was unknown. Up to now, an investigation of the light
variations seems not to have been undertaken.
   The star was observed on 11 nights between Nov. 1990 and Aug. 1992 with the
8-inch Newtonian at the author's observing station at Eckental (Germany). The
photometer was equipped with a 931A tube and Schott filters BG12 (1mm)+GG13
(2mm) for the B and GG14 (2mm) for the V colour. For a description see Grobel
(1992).
   Nearby comparison and check stars (see Figure 1) with closely matching
colour indices could be taken from Sarg and Wramdemark (1970):

            Star     RA(1991)    D(1991)   mag. V     (B-V)   (U-B)

  Var.   HD 208106   21h51m34s   61d41'   7.27-7.58   +0.14   -0.54
  Comp.  HD 207951   21h50m27s   61d45'   8.17        +0.14   -0.54
  Check  HD 207308   21h45m29s   62d15'   7.49        +0.25   -0.58

   Recent observations and measurements on a standard cluster showed that at
least for early type stars, the instrumental system matches the Johnson BV
system quite well.
   Each point of the lightcurve in Figure 2 is the mean of five consecutive
measurements. A total of 210 point could be taken in both colours, 85 per cent
of which show a standard deviation smaller than 0.015m. Throughout the
observation period, the magnitude difference check-comp. remained constant.


                                [FIGURE 1]

 Figure 1. Finding chart for HD 208106. The numbers refer to designations
 given in the paper Sarg and Wramdemark (1970).

                                [FIGURE 2]

 Figure 2. The differential B and V light and B-V colour curves of HD 208106.


   Respectively four (1991) and two (1992) minima could be secured. Due to
unequal coverage in the branches, they were determined with the tracing-paper
method.

Minimum (hel.)  Epoch

2448484.3938     -4       Min. I
  48490.3731      0       Min. I
  48498.6004      5.5     Min. II
  48501.5903      7.5     Min. II
  48843.3679    236       Min. I
  48872.5381    255.5     Min. II

   These minima are almost identical in depth and duration, so that minimum
attribution is arbitrary. The following provisional elements could be
calculated with the method of least squares and were used to reduce the
lightcurve:

     Min. I (hel.)=JD 2448490.3740+1.49574dxE

   Due to the period near 1.5d, the lightcurve could not be covered at one
location. To refine the given elements, the star will be observed further, but
observations from other longitudes are highly desirable for verification.


                                    R. GROBEL
                                    Bundesdeutsche Arbeitsgemeinschaft
                                    fur veranderliche Sterne e.V. (BAV)
                                    Munsterdamm 90, D-1000 Berlin 41



References:

Grobel, R., 1992, BAV Rundbrief, 41, 2, 3/4.
Sarg, K., Wramdemark, S., 1970, Astron. Astrophys. Suppl. Ser., 2, 251. [BIBCODE 1970A&AS....2..251S ]