On the group velocity of whistling atmospherics-Reference-Cited by-同舟云学术

On the group velocity of whistling atmospherics

Published:2021-12-20 Issue:4 Volume:7 Page:70-74
ISSN:2712-9640
Container-title:Solnechno-Zemnaya Fizika
language:en
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Author:

Guglielmi Anatol¹,Klain Boris²,Potapov Alexander³

Affiliation:

1. Schmidt Institute of Physics of the Earth, RAS

2. Borok Geophysical Observatory of IPE RAS

3. Institute of Solar-Terrestrial Physics SB RAS

Abstract

The dynamic spectrum of a whistling atmospheric is a signal of falling tone, and the group delay time of the signal as a function of frequency is formed as a result of propagation of a broadband pulse in a medium (magnetospheric plasma) with a quadratic dispersion law. In this paper, we show that for quadratic dispersion the group velocity is invariant under Galilean transformations. This means that, contrary to expectations, the group velocity is paradoxically independent of the velocity of the medium relative to the observer. A general invariance condition is found in the form of a differential equation. To explain the paradox, we introduce the concept of the dynamic spectrum of Green’s function of the path of propagation of electromagnetic waves from a pulse source (lightning discharge in the case of a whistling atmospheric) in a dispersive medium. We emphasize the importance of taking into account the motion of plasma in the experimental and theoretical study of electromagnetic wave phenomena in near-Earth space.

Publisher

Infra-M Academic Publishing House

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