抄録
We performed telescopic observations of Leonids radiant with CCD cameras on 2001 November 18. The precise positions of two radiant points corresponding to the dust trails of Comet 55P/Tempel-Tuttle’s perihelion passages in 1699 and 1 866 were predicted by McNaught and Asher. We employed a new line-detection method and tried to separate these two points. This method integrates the pixel values of a CCD image along a line direction, which enables us to detect 30-times fainter meteors than when using the usual detection methods. It can also precisely determine the angle of the line direction. Radiant points of the 2001 Leonids derived by this method were found to be consistent with those predicted by McNaught and Asher. We also measured the flux and magnitude distribution of faint meteors and succeeded in detection of faint meteor under 1O-magnitude. The cumulative flux of faint meteors is exponential growth with the index number of 2.1, and the flux 4.3 x 10(-4) x km(-2)s(-1)(mag≤+11). We have found no apparent cutoff in the magnitude range brighter than 11-magnitude.
