Fermi GBM Observations of the unusual Terrestrial Gamma-ray Flash 091214
Abstract
On 2009 December 14 GBM detected an unusual Terrestrial Gamma-ray Flash (TGF), which was more than sixty times longer than the typical TGF. Additionally, a 511 keV position annihilation line is present in the spectrum and the time history has a second peak that is well explained by magnetic mirroring of TGF-produced electrons and positrons in the Earth's magnetic field. These features strongly confirm that a small fraction of TGFs are detected not as gamma-rays, but rather as electrons and positions traveling along magnetic field lines and directly incident on the spacecraft.
- Publication:
-
AAS/High Energy Astrophysics Division #11
- Pub Date:
- November 2010
- Bibcode:
- 2010HEAD...11.2707B