Auxiliary slides

ISEE-1

ISEE-2

ISEE-1

B

Locus of = 90 degree pitch angles

Will plot as a sinusoid on a latitude/longitude projection of the unit sphere

ISEE-1 Energetic particle WAPS sensor

24 keV < E < 45 keV

63 keV < E < 95 keV

142 keV < E < 210 keV

24 keV < E < 45 keV

63 keV < E < 95 keV

142 keV < E < 210 keV

This and the another ISEE event described by Whitaker et al. [2006, 2007] are “smoking gun” events that establish that processes in the cusp accelerate particles in-situ to ring current energies.

The questions that now remain are what effects, if any, these particles have on magnetospheric processes?

Are they the source of the ring current via gradient and curvature drifts to the nightside inner magnetosphere?

Do these particles create, via charge separation, the cross polar-cap potential?

Conclusions

The Butterfly Pitch Angle DistributionParticle intensity with respect to pitch angle

Reduction of locally mirroring particles

Electrons Protons

Fritz, Space Science Reviews,Vol 95: 469-488, 2001.

26 October 1999 Electron PADs

• Electron intensities plotted as functions of both pitch angle and time

• The butterfly depression occurs nearly simultaneously across the energy spectrum

• Measured fluxes and the strength of the butterfly PAD are also nearly constant for all ten energy channels

Energy

Klida and Fritz, Ann Geophys. Submitted 2007

26 October 1999Ion PADs

Energy

• Pronounced Butterfly PAD in the middle energy channels

• As the energy range decreases, butterfly PAD onset is observed later

• Multiple observed injections with intensities peaked at 90º pitch angle at lower energies

• Overall decrease in total measured counts as the energy channel increases

Klida and Fritz, Ann Geophys. Submitted 2007

26 October 1999 Ion PADs(15.6 keV to 35.4 keV)

Klida and Fritz, Ann Geophys. Submitted 2007

Single Ion Modeling in a T96 Magnetosphere

Solar Wind Density

4.85 cm-3

Solar Wind Velocity

473 km s-1

Bx (GSM) 0.40 nT

By (GSM) 2.81 nT

Bz (GSM) -3.76 nT

X (GSM) -6.17 RE

Y (GSM) 1.85 RE

Z (GSM) -0.34 RE

Dst -33

Initial Conditions

Starting position modeled

backward in time

Klida and Fritz, Ann. Geophys. Submitted 2007

The extraterrestrial ring current:

Consider the variation of the prep and parallel pressure terms in this formula with a variable cusp source