The Geminid meteor shower of 1996-2003 from forward-scatter observations: Activity and mass distribution

摘要

Observations of the Geminid meteor shower in 1996-2003 by a forward-scatter radio system for meteor observation operating simultaneously along two baselines, Bologna-Lecce (Italy) and Bologna-Modra (Slovakia), are analysed and discussed. The activity curves of long-duration echoes (≥ 8 s) and their variations indicate a complex structure of the stream. The width of the stream at a half maximum rate level is about two days. The mass distribution exponent s and its variations in the period of the shower maximum indicate a relatively stable population of meteoroids in the stream with a population of smaller particles preceding the activity peak composed of larger particles.