Fig. 3.
From: Determining interstellar dust properties with scattered X-ray halo
Light curves of Cyg X-1 and its halo. The solid line is the light curve of the source, derived from the streak line of the observation. The gray solid line shows the light curve of the halo at 10 arcsec away from the source. The other two dashed lines show the light curves at 20 arcsec and 30 arcsec, respectively. The bin width is 5 arcsec and all of the light curves are smoothed with a window of 2 kiloseconds. PSF contaminations have been removed in the light curves of the halo.