A&A Supplement series, Vol. 129, May I 1998, 569-575
Received February 2, 1996; accepted September 19, 1997
G.B. Jia - X.F. Cen - H.Y. Ma - J.C. Wang
Send offprint request: G.B. Jia
Yunnan Observatory, Academia Sinica, P.O. Box 110, Kunming,
Yunnan, P.R. China
Results of BVRI CCD photometric monitoring and fast photometry in the I band
for the blazar OJ 287 in 1994-1995 are presented. The predicted outburst of
the blazar had been observed, the maximum appeared in 1994 November, after
that, the luminosity decreased by 1.6 mag for about three months and dropped
to near the level in 1994 April. Rapid variations with timescales of
minutes, hours and one day were observed in our observations, with small
amplitude. The amplitude of the most rapid variations (minutes) is in the
range of 
. The results of the statistical analysis of the
fast photometry data are as follows. In five nights out of six rapid
variability appeared in the sampling interval, which ranged from 3.4 minutes
to 6.5 minutes, with a rms amplitude of flux variations of 
.
The rapid variability can be explained by the model of shocks within turbulent jet or of vortices and magnetic flux tubes on accretion disk.
keywords: BL Lacertae objects: individual: OJ 287 -- galaxies: active