MU head echo observations of the 2010 Geminids: radiant, orbit, and meteor flux observing biases

作者：Kero J^*; Szasz C; Nakamura T

来源：Annales Geophysicae, 2013, 31(3): 439-449.

DOI：10.5194/angeo-31-439-2013

• Atmospheric composition and structure
• Middle atmosphere
• composition and chemistry
• Interplanetary physics
• Interplanetary dust
• Ionosphere
• Ion chemistry and composition

We report Geminid meteor head echo observations with the high-power large-aperture (HPLA) Shigaraki middle and upper atmosphere (MU) radar in Japan (34.85 degrees N, 136.10 degrees E). The MU radar observation campaign was conducted from 13 December 2010, 08:00 UTC to 15 December, 20:00 UTC and resulted in 48 h of radar data. A total of similar to 270 Geminids were observed among similar to 8800 meteor head echoes with precisely determined orbits. The Geminid head echo activity is consistent with an earlier peak than the visual Geminid activity determined by the International Meteor Organization (IMO). The observed flux of Geminids is a factor of similar to 3 lower than the previously reported flux of the 2009 Orionids measured with an identical MU radar setup. We use the observed flux ratio to discuss the relation between the head echo mass-velocity selection effect, the mass distribution indices of meteor showers and the mass threshold of the MU radar.

• 出版日期2013