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Prediction of a geosynchronous electron environment with in situ magnetic field measurements


A new approach to predict the relativistic electron flux at geosynchronous orbit has been developed. Our prediction technique is based on a linear prediction filter with the input consisting of magnetic field variations at geosynchronous orbit for 6 consecutive days. The output is a prediction, made one day ahead, of the average daily flux of >2 MeV electrons. This technique was developed with data from GOES 7 for the period from January 1994 through April 1994. The technique’s performance was tested by comparing the output results with the fluxes observed for the period from May 1994 through May 1995. The results showed that the empirical technique using in situ magnetic field measurements provides reasonably accurate forecasts of the geosynchronous electron environment one day in advance.


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Correspondence to A. Tsutai.

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Tsutai, A., Mitsui, C. & Nagai, T. Prediction of a geosynchronous electron environment with in situ magnetic field measurements. Earth Planet Sp 51, 219–223 (1999).

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  • Relativistic Electron
  • Geomagnetic Activity
  • Linear Prediction
  • Impulse Response Function
  • Prediction Skill