Physics
Scientific paper
Dec 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009agufmsm23a1580t&link_type=abstract
American Geophysical Union, Fall Meeting 2009, abstract #SM23A-1580
Physics
[2720] Magnetospheric Physics / Energetic Particles: Trapped, [2740] Magnetospheric Physics / Magnetospheric Configuration And Dynamics, [2774] Magnetospheric Physics / Radiation Belts
Scientific paper
The THEMIS mission consists of five spacecraft in highly elliptical orbits, which in a year, take the spacecraft into the magnetotail, dawn and dusk sectors, and the dayside region, where they make frequent passes through the magnetopause. The THEMIS spacecraft also carry a suite of instruments to measure low and high energy particles as well as electric and magnetic fields. Here, we are taking advantage of the THEMIS orbits to study an important region to Earth's trapped particle population: the region near the last closed drift shell, which defines the boundary between the stable trapping region and the quasi-trapping or loss region. Through this study, we hope to shed light on the particle behavior near this boundary, particularly as a potential source region for energetic electrons in Earth's outer radiation belt. We examine the flux and phase space density gradients at and beyond this boundary to estimate loss timescales and to determine which energies see the plasmasheet as a source region and which see it as a sink. We also develop a statistical understanding of how this boundary location changes under various solar wind or geomagnetic conditions and a more global understanding of the particle dynamics near this boundary by conducting the study throughout the four THEMIS orbital phases, which cover all magnetic local times over a broad range of latitudes throughout each year. We use THEMIS-SST electron fluxes from 10's to 100's keV for our particle data, and the last closed driftshell crossings are found using ephemeris data and the Tsyganenko 2001-storm model. Crossings are further confirmed by examining THEMIS plasma density and fields measurements and cross-referencing the times to the THEMIS magnetopause crossing database provided on NASA's CDAWeb. Overall, this study provides a glimpse into a region that is considered to be very important to the outer belt, relativistic electron population. Electron sources from this region are often used in models of radiation belt electron dynamics, though actual data from this region has not been studied extensively in the past. The gaps in L* are beyond the last closed drift shell, and it is at these boundaries that we conduct our study.
Friedel Reiner H.
Koller Josef
Li Xiaoliang
Reeves Geoff D.
Turner Lincoln D.
No associations
LandOfFree
A study of energetic electrons near the last closed drift shell using THEMIS-SST data does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A study of energetic electrons near the last closed drift shell using THEMIS-SST data, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A study of energetic electrons near the last closed drift shell using THEMIS-SST data will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1877871