Analysis of the Geminid meteor stream, 1958-1997, from radar observations

Results of long-term radar observations of the Geminids in the period 1958- 1997 are presented. Mean activity profiles along the Earth's passage throug h the stream show a systematic change of the peak activity and the width of the stream depending on the distribution of echo durations across the stre am. Faint particles are more concentrated in inner orbits while the large o nes dominate in the outer orbits. A skewness of the activity profiles is ev ident for echo durations T greater than or equal to 1 s. The patterns of ma ss-distribution index s and of the flux are also presented. The activity le vels of individual years show moderate scatter over the examined period exc ept in 1995 when low activity of the sporadic background results in an appa rent high activity of the shower.