COMMISSION 27 OF THE I.A.U.
              INFORMATION BULLETIN ON VARIABLE STARS
                           Number 1226

                                                    Konkoly Observatory
                                                    Budapest
                                                    1977 January 7


         PHOTOELECTRIC UBV PHOTOMETRY OF SY For

In the GCVS, SY For was classified as U Geminorum type star.
However, Wenzel (1973) doubted this classification and concluded 
from a survey on Sonneberg patrol plates that SY For is a
semiregular reddish variable star of a cycle length of 50 to 60
days and an amplitude of roughly 1.5m.
   SY For was included in a photoelectric survey of southern
U Gem stars which was carried out in Dec. 1972 with the 1 meter
telescope of the European Southern Observatory in La Silla/Chile.
The telescope was equipped with a single channel photometer and
a dry ice cooled EMI 6256 A multiplier. All observations were
obtained in the UBV system.
   The finding chart shows SY For as well as 5 field stars for
which UBV values have been obtained (Table 1). Star 1 was selected 
as main comparison star and was monitored always together with
the variable. All data were first reduced to the UBV standard
system. Afterwards, the results of the variable were corrected
according to the difference between the accompanying measurement
of the comparison star and its general mean value.
   Normally, 1 to 3 UBV sets per night were obtained. Only on
Dec. 15, SY For was monitored for 104 min revealing a total of
82 UBV observations. In none of these cases short time scale
variations exceeding 0.01m could be found. Therefore nightly 
averages were calculated and listed in Table 2.
   The present photometry confirms that SY For is a red star
probably of spectral type K. During the time of observation (10
days) it showed quite linear gradients in V and B-V (+0.042 and
-0.015 mag per day, respectively), well compatible with cycle
length and amplitude of Wenzel (1973). SY For can definitely
be excluded from the U Gem class and classified as SR star.

               Table 1

  Mean UBV Values for the Field Stars
            around SY For

Star         V     B-V     U-B    n
1          12.44   0.77    0.17  16
2          13.98   0.70    0.00   2
3          13.37   0.20    0.09   3
4          13.21   0.77   -0.11   2
5          13.93   0.72    0.15   2


              Table 2
 Nightly Averaged UBV Values of SY For

HJD          V     B-V    U-B      n
244...

1661.665   10.89   1.41   0.61     3
1664.597   11.05   1.35   0.51     2
1665.540   11.07   1.35   0.51     1
1666.573   11.09   1.34   0.42    82
1667.543   11.14   1.31   0.42     2
1668.549   11.17   1.32   0.42     2
1669.549   11.19   1.30   0.48     2
1671.559   11.31   1.26   0.49     1


                        [FIGURE 1]


                               N. VOGT
                      European Southern Observatory
                      Casilla 16317, Correo 9
                      Santiago, Chile



Reference:

Wenzel, W., 1973, IAU Inf.Bull.Var.Stars No. 763