Summary plots of the simultaneous optical-X-ray spectral analysis of Sample 1. Here the optical and X-ray fluxes are compatible with a single synchrotron spectrum. The top panel shows the X-ray (blue points) and the optical (orange points) light curves. The blue and the orange solid lines are the best-fit curves that interpolate the X-ray and optical light curves, respectively. The optical flux density extrapolated from the X-ray flux when assuming a spectral break ν_b = ν_X is shown by f_m, opt, while f_M, opt is the optical flux density extrapolated from the X-ray flux when assuming no spectral break. The grey vertical band indicates when f_opt < f_m, opt. In the middle panel, we report the evolution of the break frequency ν_b as a function of time (red error bars), while the blue line indicates the best fit with a power law (n_b ∝ t^s). In the bottom panel, we show the X-ray spectral index for each temporal bin with black error bars, while the dot-dashed line is the time-averaged value. In the same sub-plot, we also report the optical spectral index with an orange line (the yellow band is the uncertainty interval). (a) 050319, (b) 050416A, (c) 050824, (d) 051109A.