The hyperthermal ionization and high absolutemeteor velocities observed with HPLA radars |
| |
| Authors: | Asta Pellinen-Wannberg Edmond Murad Gudmund Wannberg Assar Westman |
| |
| Institution: | (1) Swedish Institute of Space Physics, Box 812 , S-981 28 Kiruna, Sweden;(2) Edmond Murad, 20 Kenrick Terrace, Newton, MA 02458, USA;(3) EISCAT Scientific Association, Box 164, S-981 23 Kiruna, Sweden |
| |
| Abstract: | High Power Large Aperture (HPLA) radars generally observe very high meteor velocities averaging over 50 km s−1. There are only a few events recorded around 30 km s−1, while meteors at 20 km s−1 or slower are very rare. This is a clear and debated contradiction to specular meteor radar results. A high plasma density
condition contributes, but the dominating phenomenon is the hyperthermal ionization mechanism due to chemical dynamics of
the ionization process. The observed high velocities can be explained in terms of high hyperthermal ionization cross-sections
for collisions between ablated meteoroid metal atoms such as Na and/or Fe and atmospheric species. |
| |
| Keywords: | HPLA hyperthermal ionization meteors velocities |
| 本文献已被 SpringerLink 等数据库收录！ |
|
