Temporal and spectral X-ray variability from the Seyfert 1 galaxy NGC 6814

The Seyfert 1 galaxy NGC 6814 was observed with the Japanese X-ray astronomy satellite Ginga in April 1990 and October 1990. Rapid flux variability with a period of ∼12000 seconds was confirmed. Furthermore, in the April observation, periodic dips in which the flux dropped nearly to zero were found. In the October observation, variability of the spectral index was found. Detailed analysis of these observations suggests an absorption model, which can explain the rapid changes in flux, as well as the the apparent variability in the spectral index.