[ITAL]UBVRI[/ITAL] Light Curves of the Seyfert Galaxy NGC 7469 During 1990–1998: Microvariability

Observations of the nuclear region of the Seyfert galaxy NGC 7469 obtained at Crimean Astrophysical Observatory with the 1.25 m telescope are presented. During 64 nights on nine observational runs between 1990 September 24 and 1998 October 22 in each spectral band of the Johnson UBVRI system, about 1500 measurements have been performed simultaneously through the round aperture 20'' in diameter using differential photometry techniques. The estimated accuracy of each measurement is about 0.01 mag. During the observing period 1990–1996 the mean luminosity of the nucleus was almost constant; only overlapping brightness fluctuations were observed. The mean luminosity level has been raised in 1996 October. The peak amplitude (maximum flux/minimum flux) Fmax/Fmin = 2.09 on the light curves was observed in the U band, while the minimum amplitude Fmax/Fmin = 1.32 was in the I band for the entire observation period.

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