First optical observations of energetic electron precipitation at 4278 Å caused by a powerful VLF transmitter

Denton, M. H. and Kosch, M. J. and Borovsky, J. E. and Clilverd, M. A. and Friedel, R. H. W. and Ulich, T. (2014) First optical observations of energetic electron precipitation at 4278 Å caused by a powerful VLF transmitter. Geophysical Research Letters, 41 (7). pp. 2237-2242. ISSN 0094-8276

[img]
Preview
PDF (grl51532)
grl51532.pdf - Published Version
Available under License Creative Commons Attribution.

Download (3MB)

Abstract

A summary is presented of experimental optical observations at 4278 Å from close to a powerful (~150 kW) VLF transmitter (call sign JXN) with a transmission frequency of 16.4 kHz. Approximately 2.5 s after transmitter turn-on, a sudden increase in optical emissions at 4278 Å was detected using a dedicated camera/charge-coupled device (CCD) monitoring system recording at a frequency of 10 Hz. The optical signal is interpreted as a burst of electron precipitation lasting ~0.5 s, due to gyro-resonant wave-particle interactions between the transmitted wave and the magnetospheric electron population. The precipitation was centered on the zenith and had no detectable spatial structure. The timing of this sequence of events is in line with theoretical predictions and previous indirect observations of precipitation. This first direct measurement of VLF-induced precipitation at 4278 Å reveals the spatial and temporal extent of the resulting optical signal close to the transmitter.

Item Type:
Journal Article
Journal or Publication Title:
Geophysical Research Letters
Additional Information:
©2014. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/1900
Subjects:
ID Code:
70485
Deposited By:
Deposited On:
21 Aug 2014 12:27
Refereed?:
Yes
Published?:
Published
Last Modified:
10 Jul 2020 03:25