HR: 0800h
AN: SM41A-1129 [Abstracts]
TI: Electron Flux Prediction in the Radiation Belt via Autoregressive Models With Solar Wind
Drivers
AU: * Presicci, M R
EM: presicci@colorado.edu
AF: Lasp/University of Colorado, 1234 Discovery Drive, Boulder, CO 80303-7814
United States
AU: Baker, D N
EM: Daniel.Baker@lasp.colorado.edu
AF: Lasp/University of Colorado, 1234 Discovery Drive, Boulder, CO 80303-7814
United States
AU: Rigler, E J
EM: jrigler@colorado.edu
AF: Lasp/University of Colorado, 1234 Discovery Drive, Boulder, CO 80303-7814
United States
AU: Weigel, R S
EM: Robert.Weigel@lasp.colorado.edu
AF: Lasp/University of Colorado, 1234 Discovery Drive, Boulder, CO 80303-7814
United States
AB:
Several prior studies have suggested the solar wind velocity acts as a driver for the relativistic electron flux in the
radiation belts. In this study, time series of ACE solar wind velocity measurements are included along with past electron
flux measurements from SAMPEX in order to predict future electron flux. Since previous flux measurements are used to predict
future flux, the autoregressive model is chosen. The inclusion of solar wind velocity measurements can also be modeled by an
autoregressive equation. Since the entire model remains autoregressive, the Kalman filter state and measurement vectors are
augmented to accommodate previous solar wind velocity along with the previous electron flux measurements. The filter
processes these measurements as they become available at different rates. ACE measurements are updated more frequently than
SAMPEX. The filter identifies the model coefficients of electron flux and solar wind velocity recursively, so that the
coefficient estimates are optimal up to the time of the most recent measurement. The improvement in prediction accuracy over
coefficient identification using Kalman filters without solar wind velocity is assessed. As a self consistent check, the
autocorrelation function for the solar wind velocity with time, using actual ACE solar wind measurement data is computed
justifying the modeling of solar wind velocity by an autoregressive equation.
DE: 2720 Energetic particles, trapped
DE: 2784 Solar wind/magnetosphere interactions
DE: 2788 Storms and substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting