Transcript Radiation Belt Electron Transport & Energization Slot region outer belt inner belt Mary K. Hudson, Magnetospheric Thrust Participants Coupled Modeling Scheme.

Radiation Belt Electron
Transport & Energization
Slot
region
outer
belt
inner
belt
Mary K. Hudson,
Magnetospheric Thrust Participants
Coupled Modeling Scheme
Solar Cycle of SAMPEX
2-6 MeV Electrons
Li et al., GRL, 2006
Response to Solar Wind Forcing

2-3 day lag at Geo
Paulikas & Blake, 1979

Prompt peak L ~3
Vassiliadis et al., 2003
SAMPEX/Vsw correlation
2-6 MeV fluxes
ULF Wave-Relativistic Electron
Correlation
Rostoker et al., GRL, 1998
Direct Coupling of Solar Wind ULF Waves
Kepko & Spence, JGR, 2003
Or Convective Growth
Magnetopause K-H
Waves Miura, JGR, 1992;
Claudepierre et al., JGR, 2008
LFM time series analysis
Halloween ’03 2-6 and >10 MeV Electrons
See filling of slot region
on storm timescale (days)
at 2-6 MeV (Baker et al.,
2004)
SAMPEX observes > 2 month
delay in high > 10 MeV fluxes
at low altitude (longer loss time)
Halloween ’03 Shock Injection
LFM-test particle simulation

W ~ 5 MeV  15 MeV

R ~ 6 RE  2.5 RE
E = - B/t :
Bz/t  E
Kress et al., JGR, 07
Halloween ’03 Shock Injection of >10
MeV (W0=1-7 MeV) Electrons
Kress et al., 2006

Low altitude SAMPEX
observations at > 10 MeV
electrons, injected
10/29/03 Looper et al., ‘06
Simulated pitch angle distribution->
Kress et al., 2006
MHD Fields Inject RadBelt
Electrons
Plasmasheet
el injection 
Elkington et al., JASTP, 2004
MHD Fields Injection of RadBelt
Electrons
Elkington et al., JASTP, 2004
PSD calculations for other
storms…
September 1998 (final)
January 1995
•The (big) September 1998 storm shows a significant change in trapped PSD as
a result of coupling to the plasmasheet.
•The more moderate storm of January 1995 showed almost no coupling with
the plasmasheet.
Elkington et al., 2008
Diffusion Rates vs. L
Radial diffusion
rates in model
ULF wave fields
D_LL ~
Radial diffusion rates in
model ULF wave fields
DLL ~ D0LN
##
LN
Perry et al., JGR, 05, includes δEφ,
δBr, δB//, freq and L-dependent
power
ULF wave DLL studies:
Elkington et al., 2003;
Ukhorskiy et al., 2005;
Fei et al., 2006
Tau(L,E) Summers 04;
Tau = days/Kp Shprits 05
Braughtigam & Albert, 2000, N = 10; Perry et al., 2006
F. Chu et
al., AGU,
F 07
=
1000 MeV/G
↑
Radial
Diffusion for
Nov 04 Storm
Baker et al., GRL, 07
2  
df
f
  2 f 
 L
D
L

ll
dt
L 
L  
July & Nov 04 Differ by SSC
Plasmapause Control of Electron
Flux Peak and Slot Region
Shprits et al., JASTP 2008
Local accel and pitchangle scattering
due to VLF/ELF waves (Whistler, EMIC)
Magnetospheric SEP Simulations
SEP Cutoffs: Brian Kress poster
SEP Cutoff rigidities calculated in a CISM
CMIT simulation of 14 May 1997 storm
IGRF field embedded within MHD inner boundary
Handoff to Forecast Transition





Radial diffusion model with DLLdetermined by LTR
ULF wave power tabulated by vsw or Kp switch
SEP cutoffs in solar-wind parametrized MHD field
snapshots
Neither involve pushing millions of particles in
time-dependent MHD fields in real time using
appropriate input spectra;
Given input spectra, e.g. SEPs from
COHREL+parametrized shock model SEP cutoffs
Given continuously available geo fluxes radbelt
f at peak flux, typically L~3-4 at 2-6 MeV,
determined from radial diffusion code including
time-dependent plasmapause loss term