Diffusion coefficient and wave amplification determination from pitch angle dependent kinetic energy of electrons

Abstract

A new expression for diffusion coefficient <i>D</i> (α) is derived, which is a function of pitch angle (α) dependent kinetic energy of electrons. Pitch angle diffusion of electrons along with amplification o f interacting VLF signals is studied at

<i>L= </i>5.1. Diffusion coefficient <i>D</i> (α) has been found to increase but temporal wave growth (<i>r</i>) and power gain (in dB) decrease with increase in pitch angle. The derived expression for <i>D</i> (α) is found to be convenient for numerical analysis. The results are interpreted in the light of observation/analysis of transmitted signals by Sonwalkar <i>et al. </i>[<i>J</i> <i>Geophys Res (USA), </i>102 (1997) 14363]. The non-observation of 2.55-2.9 kHz signals is attributed to scarcity of suitable pitch angle anisotropy, <i>A</i>(<i>E</i>_r) ·