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Figure 1: R-band light curve of 3C 454.3 in November 4-December 16, 2007. The episode of extremely fast variability indicated by the red arrow is shown in more detail in Fig. 3. |
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Figure 2: Examples of very fast variability of 3C 454.3 extracted from the light curve in Fig. 1. |
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Figure 3: The extraordinary episode of fast variability observed on December 12, 2007. |
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Figure 4: Spectral energy distributions (SEDs) of 3C 454.3 at different brightness levels in November-December 2007. Contemporaneous data are plotted with the same symbol and colour; filled symbols refer to Swift-UVOT data, while empty symbols represent ground-based observations. The curves show polynomial fits to the radio-to-UV data at the various epochs; dashed vertical lines correspond to the fit maxima. The values of the optical spectral indices are also indicated. |
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