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Abstract Terrestrial Gamma-ray Flashes (TGFs) are intense bursts of gamma rays originating from the Earth’s atmosphere, primarily produced by lightning flashes through relativistic runaway electron avalanches. Observations from the Telescope Array in Utah, equipped with a variety of lightning detection instruments, have revealed detailed insights into TGF initiation and propagation, including their optical emissions. High-speed video cameras and spectroscopic systems have captured optical emissions linked to TGFs, revealing key insights into their initiation and propagation. These findings enhance our understanding of the complex processes underlying TGFs and lightning flashes during thunderstorms.
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Three‐Dimensional Mapping of Lightning‐Produced Ionospheric Reflections
Abstract The powerful high‐frequency/very high frequency radio emissions that occur during lightning flashes can be used as a signal of opportunity to study the bottom side ionosphere. The lightning emission is bright, broad spectrum, and short in duration, providing an ideal signal of opportunity for making ionograms. This study continues previous work in Obenberger et al. (2018), where the direct line of sight signal from lightning can be cross correlated with megahertz frequency radio telescope observations to reveal ionogram traces created from the reflected lightning signals. This process was further developed to automate production of ionograms made from individual lightning flashes over the course of several hours, as well as create new techniques to detect the lightning signal using the all‐sky‐imaging mode. By using the Long Wavelength Array Sevilleta radio telescope as an interferometer, the point of reflection of the lightning signal for each frequency of the ionogram can be located in the ionosphere, instantaneously revealing density gradients within the ionosphere on minute time scales. We also explore the minimum size stations required for the application of this technique, which we found to be at least 32 antennas.
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- Award ID(s):
- 1835400
- PAR ID:
- 10458547
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Radio Science
- Volume:
- 54
- Issue:
- 11
- ISSN:
- 0048-6604
- Page Range / eLocation ID:
- p. 1129-1141
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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