COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 2336

                                    Konkoly Observatory
                                    Budapest
                                    23 May 1983

                                    HU ISSN 0374-0676


      NEW PHOTOMETRIC DATA FOR THE Ap STAR GY And = HD 9996

  GY And is a spectrum, magnetic and light variable Ap star suspected to
have a very long period (Preston, 1970). According to Preston and Wolff
(1970), spectrum, magnetic field and light appear to vary in the period of
22-24 years. Since that paper no light curve of GY And has been published.

                             [FIGURE 1]

  Figure 1  Photoelectric observations of GY And = HD 9996 from 1959 to
  1982. Filled circles: Abt and Golson (1962); oblique cross:
  Osawa and Hata (1962) crossed open circles: Geneva (unpublished);
  crosses: Stepien (1968); open circles: this paper.

 In August 1982, M. Dumont and B. Pernier performed photoelectric measurements 
in the Geneva color system, using the 76 cm telescope at the Jungfraujoch
Observatory (Switzerland). Figure 1 shows V and B-V curves between 1959 and
1982. Additional data come from Abt and Golson (1962), Osawa and Hata (1962),
Stepien (1968). Unpublished Geneva data have also been used. The data in
the Geneva system have been converted into standard UBV system.
 V and B-V variations confirm the possibility of a 22-24 year period. In
August 1982, GY And had a mean V magnitude of 6.27 and a mean B-V value of 0.12:
in 1982, GY And has reached the 1959 level in V and B-V. GY And was at light
minimum in about 1970.
 The authors wish to thank Dr. Rufener for permitting to use unpublished
data.





            M. DUMONT and J.F. LE BORGNE

                    GEOS

                  12 rue Bezout
                  75014 Paris
                  France





References:

Abt, H.A., and Golson, J.C. 1962, Ap.J., 136, 35 [BIBCODE 1962ApJ...136...35A ]
Osawa, K., and Hata, S. 1962, Ann. Tokyo Astr.0bs., 7, 209 [BIBCODE 1962AnTok...7..209O ]
Preston, G.W. 1970, P.A.S.P., 82, 878 [BIBCODE 1970PASP...82..878P ]
Preston, G.W., and Wolff, S.C. 1970, Ap.J., 160, 1071 [BIBCODE 1970ApJ...160.1071P ]
Stepien, K. 1968, Ap.J., 154, 945 [BIBCODE 1968ApJ...154..945S ]