COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                    Number 1324

                                   Konkoly Observatory
                                   Budapest
                                   1977 August 11



          A NEW VARIABLE Be STAR : HD 218 393




   HD 218393 (MWC 397, BD+49d4045) is a well-known Be star
exhibiting very pronounced spectral variations. Struve (1944),
Halliday (1950) and Doazan and Peton (1970) observed cyclic 
appearance and disappearance of the metallic shell lines, 
repeating every 35 - 40 days. Because these variations were not 
strictly periodic, they interpreted them invariably as a consequence
of some sort of atmospheric oscillations. Kriz and Harmanec
(1975) analyzed all available velocities of the star and 
suggested that the object may be a strongly interacting spectroscopic 
binary, with a possible orbital period of 38.873 days.
Polidan (1976) proved the binary nature of the star by the 
discovery of some lines of the secondary component in the infrared
part of the spectrum. According to him, the system consists of
a B3e primary and a gK1 secondary.

   We observed the star photoelectrically, in the UBV system,
at the Hvar Observatory (Jugoslavia) during two summer periods:
in 1974 and in 1976. All the measurements were carried out 
differentially, using 5 And as the primary comparison star, and
transformed to the international UBV system (for the description 
of measuring technique and reduction see Harmanec et al.
(1977) ). From absolute photometry, using a set of standard
stars, we derived the following values for 5 And: V=5.682m,
B-V =0.434m U-B=0.011m. These values give an estimate of the
spectral type of 5 And to be F4V which well agrees with the
spectroscopic classification F5V.
   All the UBV measurements of HD 218 393, which we present in
Table 1, were derived differentially, using the above (fixed)

                       Table 1
  HJD         V       B       U      B-V       U-B    N
42266.551   6.945   7.265   6.864   0.319    -0.401   5
42267.512   6.935   7.265   6.873   0.330    -0.392   2
42272.489   6.974   7.288   6.872   0.314    -0.416   6
42274.506   7.028   7.318   6.943   0.290    -0.375   3
42276.476   7.047   7.366   6.963   0.318    -0.403   6
42277.487   7.041   7.351   6.919   0.310    -0.432   4
42278.494   7.044   7.363   6.941   0.320    -0.423   4
42998.520   6.933   7.280   6.947   0.347    -0.334   4
42999.486   7.004   7.368   7.122   0.364    -0.246   2
43003.527   6.983   7.338   7.049   0.355    -0.289   7
43012.401   6.989   7.300   6.965   0.312    -0.336   4
43012.437   6.972   7.284   6.938   0.312    -0.346   4
43012.517   6.966   7.287   6.925   0.322    -0.362   3
43013.388   6.965   7.282   6.911   0.316    -0.371   3
43014.469   6.952   7.263   6.794   0.311    -0.469   4
43015.484   7.022   7.355   6.993   0.332    -0.361   3
43016.559   6.934   7.238   6.781   0.304    -0.457   4
43018.490   7.012   7.339   6.950   0.319    -0.381   2
43019.374   7.032   7.367   7.048   0.335    -0.318   5
43024.497   6.928   7.269   6.955   0.341    -0.313   4
43027.477   6.973   7.317   7.037   0.343    -0.280   4
43029.442   6.946   7.296   7.017   0.349    -0.279   6
43031.405   6.937   7.271   6.986   0.334    -0.286   2

                     [FIGURE 1]

values for 5 And. Extinction was measured every observing night.
   Measurements in all three colours are plotted in Fig. 1.
It is apparent that the brightness of the star varies for at
least 0.1m in V and B, and 0.3m in U colour. In 1974, we observed
a gradual decline taking place during about ten days. The minimum 
corresponds roughly to the phase of maximum velocity (if
the 38.9 day period is assumed). In contrast to it, more rapid
variations prevail in 1976. Clearly, our data are insufficient
for some more detailed analysis. We continue with the observations 
and appeal also to other observers interested in the
field to secure more data about this extremely interesting Be
star.




               P. HARMANEC, J. HORN, P. KOUBSKY, S. KRIZ
               Astronomical Institute, 251 65 Ondrejov,
               Czechoslovakia

               Z. IVANOVIC, K. PAVLOVSKI
               Hvar Observatory, 58450 Hvar, Jugoslavia




References:
Doazan, V., Peton, A. (1970) Astron. Astrophys. 9, 245 [BIBCODE 1970A&A.....9..245D ]
Halliday, I. (1950) J. Roy.Astron.Soc. Canada 44, 149 [BIBCODE 1950JRASC..44..149H ]
Harmanec, P., Grygar, J., Horn, J., Koubsky, P., Kriz, S.,
       Zdarsky, F., Mayer, P., Ivanovic, Z., Pavlovski, K.,
       (1977) Bull. astr. Inst. Czech. 28, 133 [BIBCODE 1977BAICz..28..133H ]
Kriz, S., Harmanec, P. (1975) Bull. astr. Inst. Czech. 26, 65 [BIBCODE 1975BAICz..26...65K ]
Polidan, R.S., (1976) in "Be and Shell Stars" (ed. by A. Slettebak),
       D. Reidel Dordrecht-Holland, pp. 405-407 [BIBCODE 1976IAUS...70..401P ]
Struve, U. (1944) Astrophys.J. 99, 75 [BIBCODE 1944ApJ....99...75S ]