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Abstract Many of the details of how terrestrial gamma‐ray flashes (TGFs) are produced, including their association with upward‐propagating in‐cloud lightning leader channels, remain poorly understood. Measurements of the low‐frequency radio emissions associated with TGF production continue to provide unique views and key insights into the electrodynamics of this process. Here we report further details on the connection between energetic in‐cloud pulses (EIPs) and TGFs. With coordinated measurements from both ground‐based radio sensors and space‐based gamma‐ray detectors on the Fermi and Reuven Ramaty High Energy Solar Spectroscopic Imager spacecraft, we find that all ten +EIPs that occurred within the searched space‐and‐time window are associated with simultaneous TGFs, including two new TGFs that were not previously identified by the gamma‐ray measurements alone. The results in this study not only solidify the tight connection between +EIPs and TGFs, but also demonstrate the practicability of detecting a subpopulation of TGFs with ground‐based radio sensors alone.
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This content will become publicly available on April 1, 2026
Optical Emissions Associated with Terrestrial Gamma-ray and Lightning Flashes at the Telescope Array Detector.
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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- Award ID(s):
- 2112709
- PAR ID:
- 10598468
- Publisher / Repository:
- R. Abbasi et al 2025 J. Phys.: Conf. Ser. 2985 012012
- Date Published:
- Journal Name:
- Journal of Physics: Conference Series
- Volume:
- 2985
- Issue:
- 1
- ISSN:
- 1742-6588
- Page Range / eLocation ID:
- 012012
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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