Quantifying Radiation Belt Electron Loss Processes at L < 4

Area of Science:

• Space Physics
• Plasma Physics
• Geophysics

Background:

• Earth's inner magnetosphere hosts energetic electrons.
• These electrons are lost through pitch-angle scattering.
• Understanding these loss processes is crucial for space weather prediction.

Purpose of the Study:

• To comprehensively analyze electron loss mechanisms in the inner magnetosphere.
• To quantify the timescales of electron decay due to various wave-particle interactions.
• To compare theoretical predictions with in-situ observations.

Main Methods:

• Utilized empirical models for wave spectra (hiss, lightning-generated whistler, VLF, EMIC waves).
• Computed pitch-angle diffusion coefficients and electron decay timescales.
• Incorporated Coulomb energy drag and accurate geomagnetic field models.

Main Results:

• Demonstrated good agreement between theoretical and observed electron lifetimes for L < 4.
• Showed sensitivity of decay timescales to plasmaspheric density models.
• Found Coulomb energy drag significantly improves agreement at L < 2.

Conclusions:

• Quasilinear pitch-angle scattering is a primary loss mechanism for inner magnetosphere electrons.
• Accurate modeling of plasmaspheric density and Coulomb losses is vital.
• Advanced geomagnetic field models refine lifetime calculations.