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Köhn C, Heumesser M, Chanrion O, Reglero V, Østgaard N, Christian HJ, Lang TJ, Blakeslee RJ, Neubert T. Employing optical lightning data to identify lightning flashes associated to terrestrial gamma-ray flashes. BULLETIN OF ATMOSPHERIC SCIENCE AND TECHNOLOGY 2024; 5:2. [PMID: 38586869 PMCID: PMC10996116 DOI: 10.1007/s42865-024-00065-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 03/18/2024] [Indexed: 04/09/2024]
Abstract
Terrestrial gamma-ray flashes (TGFs) are bursts of energetic X- and gamma-rays emitted from thunderstorms. The Atmosphere-Space Interactions Monitor (ASIM) mounted onto the International Space Station (ISS) is dedicated to measure TGFs and optical signatures of lightning; ISS LIS (Lightning Imaging Sensor) detects lightning flashes allowing for simultaneous measurements with ASIM. Whilst ASIM measures ∼ 300-400 TGFs per year, ISS LIS detects ∼ 10 6 annual lightning flashes giving a disproportion of four orders of magnitude. Based on the temporal evolution of lightning flashes and the spatial pattern of the constituing events, we present an algorithm to reduce the number of space-detected flashes potentially associated with TGFs by ∼ 60% and of associated LIS groups by ∼ 95%. We use ASIM measurements to confirm that the resulting flashes are indeed those associated with TGFs detected at approx. 400 km altitude and thus benchmark our algorithm preserving 70-80% of TGFs from concurrent ASIM-LIS measurements. We compare how the radiance, footprint size and the global distribution of lightning flashes of the reduced set relates to the average of all measured lightning flashes and do not observe any significant difference. Finally, we present a parameter study of our algorithm and discuss which parameters can be tweaked to maximize the reduction efficiency whilst keeping flashes associated to TGFs. In the future, this algorithm will hence be capable of facilitating the search for TGFs in a reduced set of lightning flashes measured from space.
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Affiliation(s)
- Christoph Köhn
- National Space Institute (DTU Space), Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Matthias Heumesser
- National Space Institute (DTU Space), Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Olivier Chanrion
- National Space Institute (DTU Space), Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Victor Reglero
- Processing Laboratory, University of Valencia, Valencia, Spain
| | - Nikolai Østgaard
- Birkeland Centre for Space Science, University of Bergen, Bergen, Norway
| | - H. J. Christian
- Department of Atmospheric Science, Earth System Science Center, University of Alabama in Huntsville, Huntsville, USA
| | - T. J. Lang
- NASA Marshall Space Flight Center, Huntsville, USA
| | | | - Torsten Neubert
- National Space Institute (DTU Space), Technical University of Denmark, Kgs. Lyngby, Denmark
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2
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van der Velde OA, Navarro-González J, Fabró F, Reglero V, Connell P, Chanrion O, López JA, Montanyà J, Neubert T, Østgaard N. Imaging of 3 bright terrestrial gamma-ray flashes by the atmosphere-space interactions monitor and their parent thunderstorms. Sci Rep 2024; 14:6946. [PMID: 38521847 PMCID: PMC10960811 DOI: 10.1038/s41598-024-57229-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 03/15/2024] [Indexed: 03/25/2024] Open
Abstract
The Atmosphere-Space Interactions Monitor (ASIM) on the International Space Station (ISS) includes an instrument designed to geolocate Terrestrial Gamma-ray Flashes (TGF) produced by thunderstorms. It does so with a coded aperture system shadowing the pixelated Low Energy Detector of the Modular X- and Gamma-ray Sensor (MXGS). Additionally, it locates associated lightning flashes with the Modular Multispectral Imaging Array (MMIA). Here we present 3 bright TGFs with very similar duration, fluency and observation distance. The innovative imaging capabilities allow us to determine the TGF position and correlate the TGF-lightning parent event in time and position simultaneously. The accurate position determination and distance to the observer allow us to perform a comparative study of TGF characteristics. These TGFs were produced in association with lightning flashes below the highest cloud tops of developing to mature convective cells. In one event, GLM (Geostationary Lightning Mapper) cloud flash rates were slowing down after the TGF while negative cloud-to-ground flashes suddenly ceased from 10 to 5 min before the TGF. An 8-stroke (strongest: -93 kA) cloud-to-ground flash occurred 31 s before the TGF. Vertical profiles from the ERA5 reanalysis data suggest TGFs may be produced in variety of tropical environments.
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Affiliation(s)
- Oscar A van der Velde
- Electrical Engineering Department, Universitat Politècnica de Catalunya - BarcelonaTech, Terrassa, Spain.
| | | | - Ferran Fabró
- Meteorological Service of Catalonia, Barcelona, Spain
| | - Víctor Reglero
- Image Processing Laboratory, University of Valencia, Valencia, Spain
| | - Paul Connell
- Image Processing Laboratory, University of Valencia, Valencia, Spain
| | - Olivier Chanrion
- Space and Earth Science and Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Jesús A López
- Electrical Engineering Department, Universitat Politècnica de Catalunya - BarcelonaTech, Terrassa, Spain
| | - Joan Montanyà
- Electrical Engineering Department, Universitat Politècnica de Catalunya - BarcelonaTech, Terrassa, Spain
| | - Torsten Neubert
- Space and Earth Science and Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Nikolai Østgaard
- Department of Physics and Technology, University of Bergen, Bergen, Norway
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3
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Optical observations of thunderstorms from the International Space Station: recent results and perspectives. NPJ Microgravity 2023; 9:12. [PMID: 36739448 PMCID: PMC9899213 DOI: 10.1038/s41526-023-00257-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 01/20/2023] [Indexed: 02/06/2023] Open
Abstract
The International Space Station (ISS) is in the lowest available orbit at ~400 km altitude, bringing instruments as close to the atmosphere as possible from the vantage point of space. The orbit inclination is 51.6°, which brings the ISS over all the low- and mid-latitude regions of the Earth and at all local times. It is an ideal platform to observe deep convection and electrification of thunderstorms, taken advantage of by the Lightning Imaging Sensor (LIS) and the Atmosphere Space Interaction Monitor (ASIM) experiments. In the coming years, meteorological satellites in geostationary orbit (~36,000 km altitude) will provide sophisticated cloud and lightning observations with almost complete coverage of the Earth's thunderstorm regions. In addition, Earth-observing satellite instruments in geostationary- and low-Earth orbit (LEO) will measure more atmospheric parameters at a higher resolution than we know today. The new infrastructure in space offers an opportunity to advance our understanding of the role of thunderstorms in atmospheric dynamics and climate change. Here, we discuss how observations from the ISS or other LEO platforms with instruments that view the atmosphere at slanted angles can complement the measurements from primarily nadir-oriented instruments of present and planned missions. We suggest that the slanted viewing geometry from LEO may resolve the altitude of electrical activity and the cloud structure where they occur, with implications for modelling thunderstorms' effects on the atmosphere's radiative properties and climate balance.
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4
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Skeie CA, Østgaard N, Mezentsev A, Bjørge‐Engeland I, Marisaldi M, Lehtinen N, Reglero V, Neubert T. The Temporal Relationship Between Terrestrial Gamma-Ray Flashes and Associated Optical Pulses From Lightning. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2022; 127:e2022JD037128. [PMID: 36246842 PMCID: PMC9541784 DOI: 10.1029/2022jd037128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 06/16/2023]
Abstract
We present 221 Terrestrial Gamma-ray Flashes (TGFs) and associated optical pulses observed by the Atmosphere-Space Interactions Monitor (ASIM) on board the International Space Station. The events were detected between the end of March 2019 and November 2020 and consist of X- and gamma-ray energy detections, as well as photometer data (180-230, 337, and 777 nm) and optical camera data (337 and 777 nm). Using the available ASIM data and applying a consistency check based on TGF characteristics and lightning detections from lightning radio atmospherics close in time, we determine the most likely position of the TGFs in relation to the photometer field of view (FoV), and the association to the observed optical pulses. Out of the 221 events we find 72 events where the TGF and optical data are determined to be associated and inside the photometer FoV. Using the measured TGF durations and the time between the onsets of the TGFs and optical pulses we find: (a) That the TGF onsets are always before or at the same time as the optical pulse onsets (taking into account cloud scattering). (b) A tendency for longer duration TGFs to have longer delays between onsets. (c) Two groups of events: (a) where there is a possible overlap between the TGFs and the optical emissions, as the TGFs last longer than the delay between onsets and (b) where the TGFs and optical emissions do not overlap, as there are long delays between the onsets, which cannot be explained by cloud scattering.
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Affiliation(s)
- C. A. Skeie
- Birkeland Centre for Space ScienceInstitute of Physics and TechnologyUniversity of BergenBergenNorway
| | - N. Østgaard
- Birkeland Centre for Space ScienceInstitute of Physics and TechnologyUniversity of BergenBergenNorway
| | - A. Mezentsev
- Birkeland Centre for Space ScienceInstitute of Physics and TechnologyUniversity of BergenBergenNorway
| | - I. Bjørge‐Engeland
- Birkeland Centre for Space ScienceInstitute of Physics and TechnologyUniversity of BergenBergenNorway
| | - M. Marisaldi
- Birkeland Centre for Space ScienceInstitute of Physics and TechnologyUniversity of BergenBergenNorway
- INAF‐OAS BolognaBolognaItaly
| | - N. Lehtinen
- Birkeland Centre for Space ScienceInstitute of Physics and TechnologyUniversity of BergenBergenNorway
| | - V. Reglero
- Imaging Processing LaboratoryUniversity of ValenciaValenciaSpain
| | - T. Neubert
- National Space InstituteTechnical University of DenmarkKongens LyngbyDenmark
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5
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Antunes de Sá AL, Marshall R, Deierling W. Energetic Intracloud Lightning in the RELAMPAGO Field Campaign. EARTH AND SPACE SCIENCE (HOBOKEN, N.J.) 2021; 8:e2021EA001856. [PMID: 34820482 PMCID: PMC8596440 DOI: 10.1029/2021ea001856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/20/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
A particular strength of lightning remote sensing is the variety of lightning types observed, each with a unique occurrence context and characteristically different emission. Distinct energetic intracloud (EIC) lightning discharges-compact intracloud lightning discharges (CIDs) and energetic intracloud pulses (EIPs)-produce intense RF radiation, suggesting large currents inside the cloud, and they also have different production mechanisms and occurrence contexts. A Low-Frequency (LF) lightning remote sensing instrument array was deployed during the RELAMPAGO field campaign in west central Argentina, designed to investigate convective storms that produce high-impact weather. LF data from the campaign can provide a valuable data set for researching the lightning context of EICs in a variety of subtropical convective storms. This paper describes the production of an LF-CID data set in RELAMPAGO and includes a preliminary analysis of CID prevalence. Geolocated lightning events and their corresponding observed waveforms from the RELAMPAGO LF data set are used in the classification of EICs. Height estimates based on skywave reflections are computed, where prefit residual data editing is used to improve robustness against outliers. Even if EIPs occurred within the network, given the low number of very high-peak current events and receiver saturation, automatic classification of EIPs may not be feasible using this data. The classification of CIDs, on the other hand, is straightforward and their properties, for both positive and negative polarity, are investigated. A few RELAMPAGO case studies are also presented, where high variability of CID prevalence in ordinary storms and high-altitude positive CIDs, possibly in overshooting tops, are observed.
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Affiliation(s)
- A. L. Antunes de Sá
- Smead Aerospace Engineering Sciences DepartmentUniversity of Colorado BoulderBoulderCOUSA
| | - R. Marshall
- Smead Aerospace Engineering Sciences DepartmentUniversity of Colorado BoulderBoulderCOUSA
| | - W. Deierling
- Smead Aerospace Engineering Sciences DepartmentUniversity of Colorado BoulderBoulderCOUSA
- National Center for Atmospheric ResearchBoulderCOUSA
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6
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Petrov NI. Synchrotron mechanism of X-ray and gamma-ray emissions in lightning and spark discharges. Sci Rep 2021; 11:19824. [PMID: 34615930 PMCID: PMC8494895 DOI: 10.1038/s41598-021-99336-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/23/2021] [Indexed: 11/13/2022] Open
Abstract
X-ray and γ-ray emissions observed in lightning and long sparks are usually connected with the bremsstrahlung of high-energy runaway electrons. Here, an alternative physical mechanism for producing X-ray and gamma-ray emissions caused by the polarization current and associated electromagnetic field moving with relativistic velocity along a curved discharge channel has been proposed. The existence of fast electromagnetic surface waves propagating along the lightning discharge channel at a speed close to the speed of light in vacuum is shown. The possibility of the production of microwave, X-ray and gamma-ray emissions by a polarization current pulse moving along a curved path via synchrotron radiation mechanism is pointed out. The existence of long tails in the power spectrum is shown, which explains observations of photon energies in the range of 10–100 MeV in the terrestrial gamma-ray flashes, as well as measured power spectrum of laboratory spark discharge.
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Affiliation(s)
- N I Petrov
- Scientific and Technological Centre of Unique Instrumentation of the Russian Academy of Sciences, 15 Butlerova str., Moscow, Russia, 117342.
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7
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Abstract
Experimental data show that in laboratory sparks, X-rays are produced in time synchronization with the meeting of streamers of opposite polarity just before the final breakdown of the discharge gap. It has been suggested that the electric field enhancement created during the collision of streamers could provide the necessary conditions for electron acceleration, even though some of the theoretical studies show that the duration of the electric field is not long enough to do so. The experimental data on laboratory discharges show that. when streamers of opposite polarity meet each other, a potential or ionization wave that renders the streamer channels conducting is initiated. This paper shows that these ionization waves that convert the discharge channels from weakly conducting to highly conducting are associated with electric fields large enough to accelerate electrons to relativistic energies.
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8
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Smith D, Trepanier J, Alnussirat ST, Cherry ML, Legault MD, Pleshinger DJ. Thunderstorms Producing Sferic-Geolocated Gamma-Ray Flashes Detected by TETRA-II. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2021; 126:e2020JD033765. [PMID: 35866003 PMCID: PMC9286440 DOI: 10.1029/2020jd033765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 06/15/2023]
Abstract
The terrestrial gamma-ray flash (TGF) and Energetic Thunderstorm Rooftop Array (TETRA-II) detected 22 X-ray/gamma-ray flash events associated with lightning between October 2015 and March 2019 across three ground-based detector locations in subtropical and tropical climates in Louisiana, Puerto Rico, and Panama. Each detector array consists of a set of bismuth germanate scintillators that record X-ray and gamma-ray bursts over the energy range 50 keV-6 MeV (million electron volts). TETRA-II events have characteristics similar to both X-ray bursts associated with lightning leaders and TGFs: sub-millisecond duration, photons up to MeV energies, and association with nearby lightning (typically within 3 km). About 20 of the 22 events are geolocated to individual lightning strokes via spatiotemporally coincident sferics. An examination of radar reflectivity and derived products related to events located within the Next Generation Weather Radar (NEXRAD) monitoring region indicates that events occur within mature cells of severe and non-severe multicellular and squall line thunderstorms, with core echo tops which are at or nearing peak altitude. Events occur in both high lightning frequency thunderstorm cells and low lightning frequency cells. Events associated with high frequency cells occur within 5 min of significant lightning jumps. Among NEXRAD-monitored events, hail is present within 8 km and 5 min of all except a single low-altitude cold weather thunderstorm. An association is seen with maximum thunderstorm development, lightning jumps, and hail cells, indicating that the TETRA-II X-ray/gamma-ray events are associated with the peak storm electrification and development of electric fields necessary for the acceleration of electrons to high energies.
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Affiliation(s)
- Deirdre Smith
- Department of Geography & AnthropologyLouisiana State UniversityBaton RougeLAUSA
| | - Jill Trepanier
- Department of Geography & AnthropologyLouisiana State UniversityBaton RougeLAUSA
| | | | - Michael L. Cherry
- Department of Physics & AstronomyLouisiana State UniversityBaton RougeLAUSA
| | - Marc D. Legault
- Department of PhysicsUniversity of Puerto Rico at BayamónBayamónPRUSA
| | - Donald J. Pleshinger
- Department of PharmacologyCenter for Lung BiologyUniversity of South AlabamaMobileALUSA
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9
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Hazards to Aircraft Crews, Passengers, and Equipment from Thunderstorm-Generated X-rays and Gamma-Rays. RADIATION 2021. [DOI: 10.3390/radiation1030015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Both observational and theoretical research in the area of atmospheric high-energy physics since about 1980 has revealed that thunderstorms produce X-rays and gamma-rays into the MeV region by a number of mechanisms. While the nature of these mechanisms is still an area of active research, enough observational and theoretical data exists to permit an evaluation of hazards presented by ionizing radiation from thunderstorms to aircraft crew, passengers, and equipment. In this paper, we use data from existing studies to evaluate these hazards in a quantitative way. We find that hazards to humans are generally low, although with the possibility of an isolated rare incident giving rise to enough radiation dose to produce noticeable symptoms. On the other hand, unshielded computer memory chips in avionics systems stand a small but non-zero chance of severe damage from thunderstorm-generated radiation and would not leave easily detectable traces of the occurrence. Should a rare phenomenon called ball lightning occur near or within an aircraft, the possibility exists of substantial damage to both equipment and personnel. Overall, radiation hazards from thunderstorms appear to be low, but should be considered and investigated with radiation monitoring equipment on sample flights.
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10
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Implications of GNSS-Inferred Tropopause Altitude Associated with Terrestrial Gamma-ray Flashes. REMOTE SENSING 2021. [DOI: 10.3390/rs13101939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The thermal structure of the environmental atmosphere associated with Terrestrial Gamma-ray Flashes (TGFs) is investigated with the combined observations from several detectors (FERMI, RHESSI, and Insight-HXMT) and GNSS-RO (SAC-C, COSMIC, GRACE, TerraSAR-X, and MetOp-A). The geographic distributions of TGF-related tropopause altitude and climatology are similar. The regional TGF-related tropopause altitude in Africa and the Caribbean Sea is 0.1–0.4 km lower than the climatology, whereas that in Asia is 0.1–0.2 km higher. Most of the TGF-related tropopause altitudes are slightly higher than the climatology, while some of them have a slightly negative bias. The subtropical TGF-producing thunderstorms are warmer in the troposphere and have a colder and higher tropopause over land than the ocean. There is no significant land–ocean difference in the thermal structure for the tropical TGF-producing thunderstorms. The TGF-producing thunderstorms have a cold anomaly in the middle and upper troposphere and have stronger anomalies than the deep convection found in previous studies.
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11
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Heumesser M, Chanrion O, Neubert T, Christian HJ, Dimitriadou K, Gordillo‐Vazquez FJ, Luque A, Pérez‐Invernón FJ, Blakeslee RJ, Østgaard N, Reglero V, Köhn C. Spectral Observations of Optical Emissions Associated With Terrestrial Gamma-Ray Flashes. GEOPHYSICAL RESEARCH LETTERS 2021; 48:2020GL090700. [PMID: 34511659 PMCID: PMC8409596 DOI: 10.1029/2020gl090700] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 06/13/2023]
Abstract
The Atmosphere-Space Interactions Monitor measures Terrestrial Gamma-Ray Flashes (TGFs) simultaneously with optical emissions from associated lightning activity. We analyzed optical measurements at 180-230, 337, and 777.4 nm related to 69 TGFs observed between June 2018 and October 2019. All TGFs are associated with optical emissions and 90% of them are at the onset of a large optical pulse, suggesting that they are connected with the initiation of current surges. A model of photon delay induced by cloud scattering suggests that the sources of the optical pulses are from 0.7 ms before to 4.4 ms after the TGFs, with a median of -10 ± 80 µs, and 1-5 km below the cloud top. The pulses have rise times comparable to lightning but longer durations. Pulse amplitudes at 337 nm are ∼3 times larger than at 777.4 nm. The results support the leader-streamer mechanism for TGF generation.
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Affiliation(s)
- Matthias Heumesser
- National Space
InstituteTechnical University of Denmark (DTU Space)Kongens LyngbyDenmark
| | - Olivier Chanrion
- National Space
InstituteTechnical University of Denmark (DTU Space)Kongens LyngbyDenmark
| | - Torsten Neubert
- National Space
InstituteTechnical University of Denmark (DTU Space)Kongens LyngbyDenmark
| | - Hugh J. Christian
- Department of Atmospheric
ScienceEarth System Science
CenterUniversity of Alabama in HuntsvilleHuntsvilleALUSA
| | - Krystallia Dimitriadou
- National Space
InstituteTechnical University of Denmark (DTU Space)Kongens LyngbyDenmark
| | | | - Alejandro Luque
- Instituto de Astrofísica de Andalucía (IAA, CSIC)GranadaSpain
| | - Francisco Javier Pérez‐Invernón
- Instituto de Astrofísica de Andalucía (IAA, CSIC)GranadaSpain
- Institut für Physik der
AtmosphäreDeutsches Zentrum für Luft‐ und Raumfahrt (DLR)OberpfaffenhofenGermany
| | | | - Nikolai Østgaard
- Birkeland Centre for Space
ScienceUniversity of BergenBergenNorway
| | - Victor Reglero
- Image Processing
LaboratoryUniversity of ValenciaValenciaSpain
| | - Christoph Köhn
- National Space
InstituteTechnical University of Denmark (DTU Space)Kongens LyngbyDenmark
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12
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Time Evolution of Storms Producing Terrestrial Gamma-Ray Flashes Using ERA5 Reanalysis Data, GPS, Lightning and Geostationary Satellite Observations. REMOTE SENSING 2021. [DOI: 10.3390/rs13040784] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In this article, we report the first investigation over time of the atmospheric conditions around terrestrial gamma-ray flash (TGF) occurrences, using GPS sensors in combination with geostationary satellite observations and ERA5 reanalysis data. The goal is to understand which characteristics are favorable to the development of these events and to investigate if any precursor signals can be expected. A total of 9 TGFs, occurring at a distance lower than 45 km from a GPS sensor, were analyzed and two of them are shown here as an example analysis. Moreover, the lightning activity, collected by the World Wide Lightning Location Network (WWLLN), was used in order to identify any links and correlations with TGF occurrence and precipitable water vapor (PWV) trends. The combined use of GPS and the stroke rate trends identified, for all cases, a recurring pattern in which an increase in PWV is observed on a timescale of about two hours before the TGF occurrence that can be placed within the lightning peak. The temporal relation between the PWV trend and TGF occurrence is strictly related to the position of GPS sensors in relation to TGF coordinates. The life cycle of these storms observed by geostationary sensors described TGF-producing clouds as intense with a wide range of extensions and, in all cases, the TGF is located at the edge of the convective cell. Furthermore, the satellite data provide an added value in associating the GPS water vapor trend to the convective cell generating the TGF. The investigation with ERA5 reanalysis data showed that TGFs mainly occur in convective environments with unexceptional values with respect to the monthly average value of parameters measured at the same location. Moreover, the analysis showed the strong potential of the use of GPS data for the troposphere characterization in areas with complex territorial morphologies. This study provides indications on the dynamics of con-vective systems linked to TGFs and will certainly help refine our understanding of their production, as well as highlighting a potential approach through the use of GPS data to explore the lightning activity trend and TGF occurrences.
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13
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Fdez-Arroyabe P, Kourtidis K, Haldoupis C, Savoska S, Matthews J, Mir LM, Kassomenos P, Cifra M, Barbosa S, Chen X, Dragovic S, Consoulas C, Hunting ER, Robert D, van der Velde OA, Apollonio F, Odzimek A, Chilingarian A, Royé D, Mkrtchyan H, Price C, Bór J, Oikonomou C, Birsan MV, Crespo-Facorro B, Djordjevic M, Salcines C, López-Jiménez A, Donner RV, Vana M, Pedersen JOP, Vorenhout M, Rycroft M. Glossary on atmospheric electricity and its effects on biology. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2021; 65:5-29. [PMID: 33025117 DOI: 10.1007/s00484-020-02013-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 08/31/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
There is an increasing interest to study the interactions between atmospheric electrical parameters and living organisms at multiple scales. So far, relatively few studies have been published that focus on possible biological effects of atmospheric electric and magnetic fields. To foster future work in this area of multidisciplinary research, here we present a glossary of relevant terms. Its main purpose is to facilitate the process of learning and communication among the different scientific disciplines working on this topic. While some definitions come from existing sources, other concepts have been re-defined to better reflect the existing and emerging scientific needs of this multidisciplinary and transdisciplinary area of research.
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Affiliation(s)
- Pablo Fdez-Arroyabe
- Geography and Planning Department, Universidad de Cantabria, 39005, Santander, Spain.
| | - Konstantinos Kourtidis
- Dept. of Environmental Engineering, Democritus University of Thrace, 67100, Xanthi, Greece
- Environmental and Networking Technologies and Applications Unit (ENTA), Athena Research and Innovation Center, 67100, Xanthi, Greece
| | - Christos Haldoupis
- Department of Physics, University of Crete, 71003 Heraklion, Crete, Greece
| | - Snezana Savoska
- Faculty of Information and Communication Technologies, University "St. Kliment Ohridski", Bitola, North Macedonia
| | - James Matthews
- School of Chemistry, Cantocks Close University of Bristol, Bristol, BS8 1TS, UK
| | - Lluis M Mir
- Université Paris-Saclay, CNRS Institut Gustave Roussy, Metabolic and systemic aspects of oncogenesis (METSY), 94805, Villejuif, France
| | - Pavlos Kassomenos
- Department of Physics, Lab. of Meteorology, University Campus, University of Ioannina, 45100, Ioannina, Greece
| | - Michal Cifra
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014, /57 182 51, Prague, Czechia
| | - Susana Barbosa
- INESC Technology and Science - INESC TEC, Porto, Portugal
| | - Xuemeng Chen
- Institute of Physics, University of Tartu, W. Ostwaldi 1, EE-50411, Tartu, Estonia
| | - Snezana Dragovic
- University of Belgrade, Vinca Institute of Nuclear Sciences, Belgrade, Serbia
| | - Christos Consoulas
- Laboratory of Experimental Physiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Ellard R Hunting
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Daniel Robert
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Oscar A van der Velde
- Lightning Research Group, Electrical Engineering Department, Polytechnic University of Catalonia - BarcelonaTech, Colon 1, 08222, Terrassa, Spain
| | - Francesca Apollonio
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome, Italy
| | - Anna Odzimek
- Institute of Geophysics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Dominic Royé
- Department of Geography, University of Santiago de Compostela, Santiago, Spain
| | | | - Colin Price
- Department of Geophysics, Porter School of the Environment and Earth Sciences, Tel Aviv University, 6997801, Tel Aviv, Israel
| | - József Bór
- Geodetic and Geophysical Institute, Research Centre for Astronomy and Earth Sciences, Sopron, Hungary
| | - Christina Oikonomou
- Frederick University 7, Y. Frederickou Str. Pallouriotisa, 1036, Nicosia, Cyprus
| | - Marius-Victor Birsan
- Department of Research and Meteo Infrastructure Projects, Meteo Romania (National Meteorological Administration), Bucharest, Romania
| | - Benedicto Crespo-Facorro
- Department of Psychiatry, University of Sevilla, HU Virgen del Rocio IBIS, CIBERSAM, Seville, Spain
| | - Milan Djordjevic
- Department of Geography, Faculty of Sciences and Mathematics, University of Niš, Niš, Serbia
| | - Ciro Salcines
- Health and Safety Unit, Infrastructure Service, University of Cantabria, Avd. de los Castros, 54 39005, Santander, Cantabria, Spain
| | - Amparo López-Jiménez
- Hydraulic and Environmental Engineering Department, Universitat Politécnica de Valencia, Camino de Vera s/n 46022, Valencia, Spain
| | - Reik V Donner
- Department of Water, Environment, Construction and Safety, Magdeburg-Stendal University of Applied Sciences, Breitscheidstr. 2, 39114, Magdeburg, Germany
- Potsdam Institute for Climate Impact Research (PIK) - Member of the Leibniz Association, Telegrafenberg A31, 14773, Potsdam, Germany
| | - Marko Vana
- Institute of Physics, University of Tartu, W. Ostwaldi 1, EE-50411, Tartu, Estonia
| | - Jens Olaf Pepke Pedersen
- National Space Institute, DTU Space, Technical University of Denmark, Centrifugevej 356, DK-2800, Kgs. Lyngby, Denmark
| | | | - Michael Rycroft
- CAESAR Consultancy, 35 Millington Road, Cambridge, CB3 9HW, UK
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14
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Abstract
Exposure of aircrew to cosmic radiation has been recognized as an occupational health risk for several decades. Based on the recommendations by the International Commission on Radiological Protection (ICRP), many countries and their aviation authorities, respectively have either stipulated legal radiation protection regulations, e.g., in the European Union or issued corresponding advisory circulars, e.g., in the United States of America. Additional sources of ionizing and non-ionizing radiation, e.g., due to weather phenomena have been identified and discussed in the scientific literature in recent years. This article gives an overview of the different generally recognized sources due to weather as well as space weather phenomena that contribute to radiation exposure in the atmosphere and the associated radiation effects that might pose a risk to aviation safety at large, including effects on human health and avionics. Furthermore, potential mitigation measures for several radiation sources and the prerequisites for their use are discussed.
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15
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Liu N, Dwyer JR, Tilles JN. Electromagnetic Radiation Spectrum of a Composite System. PHYSICAL REVIEW LETTERS 2020; 125:025101. [PMID: 32701353 DOI: 10.1103/physrevlett.125.025101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 05/27/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
In many physics fields, the radio emission of a composite system composed of a large number of randomly occurring but similar emission sources is encountered. In general, the composite system lasts longer than each individual component and individual source currents vary much more rapidly. This Letter presents a theory to understand the electromagnetic radiation spectrum of such a system. If the temporal distribution of the random occurrence of the component and the distribution to describe the relevant emission source properties are known, the spectrum of the composite system can be readily found from this theory. There are two main terms that define the spectrum: one term results from the coherent summation of the contributions from individual sources and is proportional to the square of the total number of the components in the system; the other term results from an incoherent summation and is proportional to the first power of that number. This can lead to drastically different spectral magnitudes in different spectral regions, typically with the spectral magnitude in the lower frequency region many orders of magnitude stronger than that in the higher frequency region.
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Affiliation(s)
- Ningyu Liu
- Department of Physics and Astronomy & Space Science Center (EOS), The University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Joseph R Dwyer
- Department of Physics and Astronomy & Space Science Center (EOS), The University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Julia N Tilles
- Department of Physics and Astronomy & Space Science Center (EOS), The University of New Hampshire, Durham, New Hampshire 03824, USA
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16
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Schmalzried A, Luque A. Influence of Elastic Scattering on Electron Swarm Distribution in Electrified Gases. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2020; 125:e2019JD031564. [PMID: 32728499 PMCID: PMC7380314 DOI: 10.1029/2019jd031564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 06/11/2023]
Abstract
The propagation of energetic electrons through air is one key component in the generation of high-energy atmospheric phenomena such as lightning-generated X-ray bursts, terrestrial gamma ray flashes (TGFs), and gamma ray glows. We show here that models for this propagation can be considerably affected by the parameterization of the differential cross section of elastic scattering of electrons on the molecular components of air. We assess existing parameterizations and propose a more accurate one that builds upon the most up-to-date measurements. Then we conclude that by overweighting the forward scattering probability, previous works may have overestimated the production of runaway electrons under high electric fields close to the thermal runaway threshold.
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Affiliation(s)
- A. Schmalzried
- Instituto de Astrofísica de Andalucía (IAA)CSICGranadaSpain
| | - A. Luque
- Instituto de Astrofísica de Andalucía (IAA)CSICGranadaSpain
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17
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Mailyan BG, Nag A, Dwyer JR, Said RK, Briggs MS, Roberts OJ, Stanbro M, Rassoul HK. Gamma-Ray and Radio-Frequency Radiation from Thunderstorms Observed from Space and Ground. Sci Rep 2020; 10:7286. [PMID: 32350301 PMCID: PMC7190649 DOI: 10.1038/s41598-020-63437-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 03/23/2020] [Indexed: 11/09/2022] Open
Abstract
Terrestrial gamma ray flashes (TGFs) are a class of enigmatic electrical discharges in the Earth’s atmosphere. In this study, we analyze an unprecedentedly large dataset comprised of 2188 TGFs whose signatures were simultaneously measured using space- and ground-based detectors over a five-year period. The Gamma-ray Burst Monitor (GBM) on board the Fermi spacecraft provided the energetic radiation measurements. Radio frequency (RF) measurements were obtained from the Global Lightning Dataset (GLD360). Here we show the existence of two categories of TGFs − those that were accompanied by quasi-simultaneous electromagnetic pulses (EMPs) detected by the GLD360 and those without such simultaneous EMPs. We examined, for the first time, the dependence of the TGF-associated EMP-peak-amplitude on the horizontal offset distance between the Fermi spacecraft and the TGF source. TGFs detected by the GBM with sources at farther horizontal distances are expected to be intrinsically brighter and were found to be associated with EMPs having larger median peak-amplitudes. This provides independent evidence that the EMPs and TGFs are produced by the same phenomenon, rather than the EMPs being from “regular” lightning in TGF-producing thunderstorms.
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Affiliation(s)
- B G Mailyan
- Florida Institute of Technology, Melbourne, Florida, USA. .,The University of Alabama in Huntsville, Huntsville, Alabama, USA.
| | - A Nag
- Florida Institute of Technology, Melbourne, Florida, USA.
| | - J R Dwyer
- University of New Hampshire, Durham, New Hampshire, USA
| | - R K Said
- Vaisala Inc., Louisville, Colorado, USA
| | - M S Briggs
- The University of Alabama in Huntsville, Huntsville, Alabama, USA
| | - O J Roberts
- Universities Space Research Association, Huntsville, Alabama, USA
| | - M Stanbro
- The University of Alabama in Huntsville, Huntsville, Alabama, USA
| | - H K Rassoul
- Florida Institute of Technology, Melbourne, Florida, USA
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18
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Neubert T, Østgaard N, Reglero V, Chanrion O, Heumesser M, Dimitriadou K, Christiansen F, Budtz-Jørgensen C, Kuvvetli I, Rasmussen IL, Mezentsev A, Marisaldi M, Ullaland K, Genov G, Yang S, Kochkin P, Navarro-Gonzalez J, Connell PH, Eyles CJ. A terrestrial gamma-ray flash and ionospheric ultraviolet emissions powered by lightning. Science 2020; 367:183-186. [PMID: 31826957 DOI: 10.1126/science.aax3872] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 10/31/2019] [Indexed: 11/02/2022]
Abstract
Terrestrial gamma-ray flashes (TGFs) are transient gamma-ray emissions from thunderstorms, generated by electrons accelerated to relativistic energies in electric fields. Elves are ultraviolet and optical emissions excited in the lower ionosphere by electromagnetic waves radiated from lightning current pulses. We observed a TGF and an associated elve using the Atmosphere-Space Interactions Monitor on the International Space Station. The TGF occurred at the onset of a lightning current pulse that generated an elve, in the early stage of a lightning flash. Our measurements suggest that the current onset is fast and has a high amplitude-a prerequisite for elves-and that the TGF is generated in the electric fields associated with the lightning leader.
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Affiliation(s)
- Torsten Neubert
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark.
| | - Nikolai Østgaard
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Victor Reglero
- Image Processing Laboratory, University of Valencia, Valencia, Spain
| | - Olivier Chanrion
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark
| | - Matthias Heumesser
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark
| | - Krystallia Dimitriadou
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark
| | - Freddy Christiansen
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark
| | - Carl Budtz-Jørgensen
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark
| | - Irfan Kuvvetli
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark
| | - Ib Lundgaard Rasmussen
- National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark
| | - Andrey Mezentsev
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Martino Marisaldi
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway.,Astrophysics and Space Science Observatory, National Institute for Astrophysics, Bologna, Italy
| | - Kjetil Ullaland
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Georgi Genov
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Shiming Yang
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Pavlo Kochkin
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
| | | | - Paul H Connell
- Image Processing Laboratory, University of Valencia, Valencia, Spain
| | - Chris J Eyles
- Image Processing Laboratory, University of Valencia, Valencia, Spain
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19
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Tiberia A, Dietrich S, Porcù F, Marisaldi M, Ursi A, Tavani M. Gamma ray storms: preliminary meteorological analysis of AGILE TGFs. RENDICONTI LINCEI. SCIENZE FISICHE E NATURALI 2019. [DOI: 10.1007/s12210-019-00775-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Ten years of AGILE: the mission and scientific highlights. RENDICONTI LINCEI. SCIENZE FISICHE E NATURALI 2019. [DOI: 10.1007/s12210-019-00841-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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21
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Wada Y, Enoto T, Nakazawa K, Furuta Y, Yuasa T, Nakamura Y, Morimoto T, Matsumoto T, Makishima K, Tsuchiya H. Downward Terrestrial Gamma-Ray Flash Observed in a Winter Thunderstorm. PHYSICAL REVIEW LETTERS 2019; 123:061103. [PMID: 31491171 DOI: 10.1103/physrevlett.123.061103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/19/2019] [Indexed: 06/10/2023]
Abstract
During a winter thunderstorm on 24 November 2017, a strong burst of gamma rays with energies up to ∼10 MeV was detected coincident with a lightning discharge, by scintillation detectors installed at the Kashiwazaki-Kariwa Nuclear Power Station at sea level in Japan. The burst had a subsecond duration, which is suggestive of photoneutron production. The leading part of the burst was resolved into four intense gamma-ray bunches, each coincident with a low-frequency radio pulse. These bunches were separated by 0.7-1.5 ms, with a duration of ≪1 ms each. Thus, the present burst may be considered as a "downward" terrestrial gamma-ray flash (TGF), which is analogous to upgoing TGFs observed from space. Although the scintillation detectors were heavily saturated by these bunches, the total dose associated with them was successfully measured by ionization chambers, employed by nine monitoring posts surrounding the power plant. From this information and Monte Carlo simulations, the present downward TGF is suggested to have taken place at an altitude of 2500±500 m, involving 8_{-4}^{+8}×10^{18} avalanche electrons with energies above 1 MeV. This number is comparable to those in upgoing TGFs.
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Affiliation(s)
- Y Wada
- Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- High Energy Astrophysics Laboratory, Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Enoto
- High Energy Astrophysics Laboratory, Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- The Hakubi Center for Advanced Research and Department of Astronomy, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto, Kyoto 606-8502, Japan
| | - K Nakazawa
- Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Y Furuta
- Collaborative Laboratories for Advanced Decommissioning Science, Japan Atomic Energy Agency, 2-4 Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
| | - T Yuasa
- Block 4B, Boon Tiong Road, Singapore 165004, Singapore
| | - Y Nakamura
- Kobe City College of Technology, 8-3 Gakuen-Higashimachi, Nishi-ku, Kobe, Hyogo 651-2194, Japan
| | - T Morimoto
- Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8502, Japan
| | - T Matsumoto
- Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - K Makishima
- Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- High Energy Astrophysics Laboratory, Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8683, Japan
| | - H Tsuchiya
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency, 2-4 Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
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22
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Østgaard N, Christian HJ, Grove JE, Sarria D, Mezentsev A, Kochkin P, Lehtinen N, Quick M, Al‐Nussirat S, Wulf E, Genov G, Ullaland K, Marisaldi M, Yang S, Blakeslee RJ. Gamma Ray Glow Observations at 20-km Altitude. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2019; 124:7236-7254. [PMID: 31598449 PMCID: PMC6774313 DOI: 10.1029/2019jd030312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/18/2019] [Accepted: 04/24/2019] [Indexed: 06/10/2023]
Abstract
In the spring of 2017 an ER-2 aircraft campaign was undertaken over continental United States to observe energetic radiation from thunderstorms and lightning. The payload consisted of a suite of instruments designed to detect optical signals, electric fields, and gamma rays from lightning. Starting from Georgia, USA, 16 flights were performed, for a total of about 70 flight hours at a cruise altitude of 20 km. Of these, 45 flight hours were over thunderstorm regions. An analysis of two gamma ray glow events that were observed over Colorado at 21:47 UT on 8 May 2017 is presented. We explore the charge structure of the cloud system, as well as possible mechanisms that can produce the gamma ray glows. The thundercloud system we passed during the gamma ray glow observation had strong convection in the core of the cloud system. Electric field measurements combined with radar and radio measurements suggest an inverted charge structure, with an upper negative charge layer and a lower positive charge layer. Based on modeling results, we were not able to unambiguously determine the production mechanism. Possible mechanisms are either an enhancement of cosmic background locally (above or below 20 km) by an electric field below the local threshold or an enhancement of the cosmic background inside the cloud but then with normal polarity and an electric field well above the Relativistic Runaway Electron Avalanche threshold.
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Affiliation(s)
- N. Østgaard
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - H. J. Christian
- Department of Atmospheric ScienceUniversity of AlabamaHuntsvilleALUSA
| | - J. E. Grove
- U.S. Naval Research LaboratoryWashingtonDCUSA
| | - D. Sarria
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - A. Mezentsev
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - P. Kochkin
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - N. Lehtinen
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - M. Quick
- NASA Marshal Space Flight CenterHuntsvilleALUSA
| | - S. Al‐Nussirat
- Department of Physics and AstronomyLouisiana State UniversityBaton RougeLAUSA
| | - E. Wulf
- U.S. Naval Research LaboratoryWashingtonDCUSA
| | - G. Genov
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - K. Ullaland
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - M. Marisaldi
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
| | - S. Yang
- Birkeland Centre for Space ScienceUniversity of BergenBergenNorway
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23
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Catalog of 2017 Thunderstorm Ground Enhancement (TGE) events observed on Aragats. Sci Rep 2019; 9:6253. [PMID: 31000757 PMCID: PMC6472419 DOI: 10.1038/s41598-019-42786-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 04/04/2019] [Indexed: 12/05/2022] Open
Abstract
The natural electron accelerator in the clouds above Aragats high-altitude research station in Armenia operates continuously in 2017 providing more than 100 Thunderstorm Ground enhancements (TGEs). Most important discovery based on analysis of 2017 data is observation and detailed description of the long-lasting TGEs. We present TGE catalog for 2 broad classes according to presence or absence of the high-energy particles. In the catalog was summarized several key parameters of the TGEs and related meteorological and atmospheric discharge observations. The statistical analysis of the data collected in tables reveals the months when TGEs are more frequent, the daytime when TGEs mostly occurred, the mean distance to lightning flash that terminates TGE and many other interesting relations. Separately was discussed the sharp count rate decline and following removal of high-energy particles from the TGE flux after a lightning flash. ADEI multivariate visualization and statistical analysis platform make analytical work on sophisticated problems rather easy; one can try and test many hypotheses very fast and come to a definite conclusion allowing crosscheck and validation
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24
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Malagón‐Romero A, Luque A. Spontaneous Emergence of Space Stems Ahead of Negative Leaders in Lightning and Long Sparks. GEOPHYSICAL RESEARCH LETTERS 2019; 46:4029-4038. [PMID: 31244497 PMCID: PMC6582701 DOI: 10.1029/2019gl082063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/13/2019] [Accepted: 03/15/2019] [Indexed: 06/09/2023]
Abstract
We investigate the emergence of space stems ahead of negative leaders. These are luminous spots that appear ahead of an advancing leader mediating the leader's stepped propagation. We show that space stems start as regions of locally depleted conductivity that form in the streamers of the corona around the leader. An attachment instability enhances the electric field leading to strongly inhomogeneous, bright, and locally warmer regions ahead of the leader that explain the existing observations. Since the attachment instability is only triggered by fields above 10 kV/cm and internal electric fields are lower in positive than in negative streamers, our results explain why, although common in negative leaders, space stems, and stepping are hardly observed if not absent in positive leaders. Further work is required to fully explain the streamer to leader transition, which requires an electric current persisting for timescales longer than the typical attachment time of electrons, around 100 ns.
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25
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Hariharan B, Chandra A, Dugad SR, Gupta SK, Jagadeesan P, Jain A, Mohanty PK, Morris SD, Nayak PK, Rakshe PS, Ramesh K, Rao BS, Reddy LV, Zuberi M, Hayashi Y, Kawakami S, Ahmad S, Kojima H, Oshima A, Shibata S, Muraki Y, Tanaka K. Measurement of the Electrical Properties of a Thundercloud Through Muon Imaging by the GRAPES-3 Experiment. PHYSICAL REVIEW LETTERS 2019; 122:105101. [PMID: 30932668 DOI: 10.1103/physrevlett.122.105101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 01/21/2019] [Indexed: 06/09/2023]
Abstract
The GRAPES-3 muon telescope located in Ooty, India records rapid (∼10 min) variations in the muon intensity during major thunderstorms. Out of a total of 184 thunderstorms recorded during the interval of April 2011-December 2014, the one on December 1, 2014 produced a massive potential of 1.3 GV. The electric field measured by four well-separated (up to 6 km) monitors on the ground was used to help estimate some of the properties of this thundercloud, including its altitude and area that were found to be 11.4 km above mean sea level and ≥380 km^{2}, respectively. A charging time of 6 min to reach 1.3 GV implied the delivery of a power of ≥2 GW by this thundercloud that was moving at a speed of ∼60 km h^{-1}. This work possibly provides the first direct evidence for the generation of gigavolt potentials in thunderclouds that could also possibly explain the production of highest-energy (100 MeV) gamma rays in the terrestrial gamma-ray flashes.
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Affiliation(s)
- B Hariharan
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - A Chandra
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - S R Dugad
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - S K Gupta
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - P Jagadeesan
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - A Jain
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - P K Mohanty
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - S D Morris
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - P K Nayak
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - P S Rakshe
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - K Ramesh
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - B S Rao
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - L V Reddy
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - M Zuberi
- Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
| | - Y Hayashi
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- Graduate School of Science, Osaka City University, Osaka 558-8585, Japan
| | - S Kawakami
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- Graduate School of Science, Osaka City University, Osaka 558-8585, Japan
| | - S Ahmad
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- Aligarh Muslim University, Aligarh 202002, India
| | - H Kojima
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- College of Engineering, Chubu University, Kasugai, Aichi 487-8501, Japan
| | - A Oshima
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- College of Engineering, Chubu University, Kasugai, Aichi 487-8501, Japan
| | - S Shibata
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- College of Engineering, Chubu University, Kasugai, Aichi 487-8501, Japan
| | - Y Muraki
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Aichi 446-8601, Japan
| | - K Tanaka
- Cosmic Ray Laboratory, Raj Bhavan, Ooty 643001, India
- Graduate School of Information Sciences, Hiroshima City University, Hiroshima 731-3194, Japan
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26
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Albrechtsen KH, Østgaard N, Berge N, Gjesteland T. Observationally Weak TGFs in the RHESSI Data. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2019; 124:287-298. [PMID: 31007988 PMCID: PMC6472622 DOI: 10.1029/2018jd029272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 11/20/2018] [Accepted: 11/22/2018] [Indexed: 06/09/2023]
Abstract
Terrestrial gamma ray flashes (TGFs) are sub-millisecond bursts of high energetic gamma radiation associated with intracloud flashes in thunderstorms. In this paper we use the simultaneity of lightning detections by World Wide Lightning Location Network to find TGFs in the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) data that are too faint to be identified by standard search algorithms. A similar approach has been used in an earlier paper, but here we expand the data set to include all years of RHESSI + World Wide Lightning Location Network data and show that there is a population of observationally weak TGFs all the way down to 0.22 of the RHESSI detection threshold (three counts in the detector). One should note that the majority of these are "normal" TGFs that are produced further away from the subsatellite point (and experience a 1/r 2 effect) or produced at higher latitudes with a lower tropoause and thus experience increased atmospheric attenuation. This supports the idea that the TGF production rate is higher than currently reported. We also show that compared to lightning flashes, TGFs are more partial to ocean and coastal regions than over land.
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Affiliation(s)
- K. H. Albrechtsen
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - N. Østgaard
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - N. Berge
- LPC2E, CNRSUniversity of OrleansOrleansFrance
| | - T. Gjesteland
- Department of Engineering ScienceUniversity of AgderGrimstadNorway
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Abbasi R, Belz J, Le Von R, Rodeheffer D, Krehbiel P, Remington J, Rison W. Ground-Based Observations of Terrestrial Gamma Ray Flashes Associated with Downward-Directed Lightning Leaders. EPJ WEB OF CONFERENCES 2019. [DOI: 10.1051/epjconf/201919703002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Terrestrial gamma-ray flashes (TGFs) are bursts of gamma-rays initiated in the Earth’s atmosphere. TGFs were serendipitously first observed over twenty years ago by the BATSE gamma ray satellite experiment. Since then, several satellite experiments have shown that TGFs are produced in the upward negative breakdown stage at the start of intracloud lightning discharges. In this proceeding, we present ground-based observation of TGFs produced by downward negative breakdown occurring at the beginning of negative cloud-to-ground flashes.
The Terrestrial gamma-ray flashes discussed in this work were detected between 2014-2017 at ground level by the Telescope Array surface detector (TASD) together with Lightning Mapping Array (LMA) and the slow electric field antenna (SA). The TASD detector is a 700 km2 ultra high energy cosmic ray detector in the southwestern desert of Utah. It is comprised of 507 (3 m2) plastic scintillator detectors on a 1.2 km square grid. The LMA detector, a three-dimensional total lightning location system, is comprised of nine stations located within and around the array. The slow electric field antenna records the electric field change in lightning discharges.
The observed Gamma ray showers were detected in the first 1-2 ms of downward negative breakdown prior to cloud-to-ground lightning strikes. The shower sources were observed by the LMA detector at altitudes of a few kilometers above ground level. The detected energetic burst showers have a footprint on the ground typically ~ 3-5 km in diameter. The bursts comprise of several (2-5) individual pulses, each of which have a span of a few to tens of microseconds and an overall duration of several hundred microseconds. Using a forward-beamed cone of half-angle of 16 degrees, GEANT simulation studies indicate that the showers are consistent with gamma rays of 1012 - 1014 primary photons. We hypothesize that the observed terrestrial gamma-ray flashes are similar to those detected by satellites, but that the ground-based observations are closer to the source and therefore are able to observe weaker sources and report on the structure of the temporal distribution at the source. This result and future studies will enable us to better identify and constrain the mechanisms of downward TGF production.
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Cohen MB, Said RK, Paschal EW, McCormick JC, Gross NC, Thompson L, Higginson-Rollins M, Inan US, Chang J. Broadband longwave radio remote sensing instrumentation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:094501. [PMID: 30278759 DOI: 10.1063/1.5041419] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 08/17/2018] [Indexed: 06/08/2023]
Abstract
We present the performance characteristics of a high-sensitivity radio receiver for the frequency band 0.5-470 kHz, known as the Low Frequency Atmospheric Weather Electromagnetic System for Observation, Modeling, and Education, or LF AWESOME. The receiver is an upgraded version of the VLF AWESOME, completed in 2004, which provided high sensitivity broadband radio measurements of natural lightning emissions, transmitting beacons, and radio emissions from the near-Earth space environment. It has been deployed at many locations worldwide and used as the basis for dozens of scientific studies. We present here a significant upgrade to the AWESOME, in which the frequency range has been extended to include the LF and part of the medium frequency (MF) bands, the sensitivity improved by 10-25 dB to be as low as 0.03 fT/ Hz , depending on the frequency, and timing error reduced to 15-20 ns range. The expanded capabilities allow detection of radio atmospherics from lightning strokes at global distances and multiple traverses around the world. It also allows monitoring of transmitting beacons in the LF/MF band at thousands of km distance. We detail the specification of the LF AWESOME and demonstrate a number of scientific applications. We also describe and characterize a new algorithm for minimum shift keying demodulation for VLF/LF transmitters for ionospheric remote sensing applications.
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Affiliation(s)
- Morris B Cohen
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0360, USA
| | - Ryan K Said
- Vaisala, Inc., Boulder Operations, Louisville, Colorado 80027, USA
| | - Evans W Paschal
- Whistler Radio Services, Anderson Island, Washington 98303, USA
| | - Jackson C McCormick
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0360, USA
| | - Nicholas C Gross
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0360, USA
| | | | - Marc Higginson-Rollins
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0360, USA
| | - Umran S Inan
- Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA
| | - Jeffrey Chang
- Omnicell, Inc., Mountain View, California 94043, USA
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29
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Köhn C, Chanrion O, Neubert T. High-Energy Emissions Induced by Air Density Fluctuations of Discharges. GEOPHYSICAL RESEARCH LETTERS 2018; 45:5194-5203. [PMID: 30034044 PMCID: PMC6049893 DOI: 10.1029/2018gl077788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 04/24/2018] [Accepted: 04/25/2018] [Indexed: 06/08/2023]
Abstract
Bursts of X-rays and γ-rays are observed from lightning and laboratory sparks. They are bremsstrahlung from energetic electrons interacting with neutral air molecules, but it is still unclear how the electrons achieve the required energies. It has been proposed that the enhanced electric field of streamers, found in the corona of leader tips, may account for the acceleration; however, their efficiency is questioned because of the relatively low production rate found in simulations. Here we emphasize that streamers usually are simulated with the assumption of homogeneous gas, which may not be the case on the small temporal and spatial scales of discharges. Since the streamer properties strongly depend on the reduced electric field E/n, where n is the neutral number density, fluctuations may potentially have a significant effect. To explore what might be expected if the assumption of homogeneity is relaxed, we conducted simple numerical experiments based on simulations of streamers in a neutral gas with a radial gradient in the neutral density, assumed to be created, for instance, by a previous spark. We also studied the effects of background electron density from previous discharges. We find that X-radiation and γ-radiation are enhanced when the on-axis air density is reduced by more than ∼25%. Pre-ionization tends to reduce the streamer field and thereby the production rate of high-energy electrons; however, the reduction is modest. The simulations suggest that fluctuations in the neutral densities, on the temporal and spacial scales of streamers, may be important for electron acceleration and bremsstrahlung radiation.
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Affiliation(s)
- C. Köhn
- National Space Institute (DTU Space)Technical University of DenmarkLyngbyDenmark
| | - O. Chanrion
- National Space Institute (DTU Space)Technical University of DenmarkLyngbyDenmark
| | - T. Neubert
- National Space Institute (DTU Space)Technical University of DenmarkLyngbyDenmark
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30
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Wolf JP. Short-pulse lasers for weather control. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:026001. [PMID: 28783040 DOI: 10.1088/1361-6633/aa8488] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Filamentation of ultra-short TW-class lasers recently opened new perspectives in atmospheric research. Laser filaments are self-sustained light structures of 0.1-1 mm in diameter, spanning over hundreds of meters in length, and producing a low density plasma (1015-1017 cm-3) along their path. They stem from the dynamic balance between Kerr self-focusing and defocusing by the self-generated plasma and/or non-linear polarization saturation. While non-linearly propagating in air, these filamentary structures produce a coherent supercontinuum (from 230 nm to 4 µm, for a 800 nm laser wavelength) by self-phase modulation (SPM), which can be used for remote 3D-monitoring of atmospheric components by Lidar (Light Detection and Ranging). However, due to their high intensity (1013-1014 W cm-2), they also modify the chemical composition of the air via photo-ionization and photo-dissociation of the molecules and aerosols present in the laser path. These unique properties were recently exploited for investigating the capability of modulating some key atmospheric processes, like lightning from thunderclouds, water vapor condensation, fog formation and dissipation, and light scattering (albedo) from high altitude clouds for radiative forcing management. Here we review recent spectacular advances in this context, achieved both in the laboratory and in the field, reveal their underlying mechanisms, and discuss the applicability of using these new non-linear photonic catalysts for real scale weather control.
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Affiliation(s)
- J P Wolf
- Department of Applied Physics (GAP), University of Geneva, 1211 Geneva 4, Switzerland
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31
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Mezentsev A, Lehtinen N, Østgaard N, Pérez‐Invernón FJ, Cummer SA. Spectral Characteristics of VLF Sferics Associated With RHESSI TGFs. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2018; 123:139-159. [PMID: 29527426 PMCID: PMC5832322 DOI: 10.1002/2017jd027624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/02/2017] [Accepted: 12/03/2017] [Indexed: 06/09/2023]
Abstract
We compared the modeled energy spectral density of very low frequency (VLF) radio emissions from terrestrial gamma ray flashes (TGFs) with the energy spectral density of VLF radio sferics recorded by Duke VLF receiver simultaneously with those TGFs. In total, six events with world wide lightning location network (WWLLN) defined locations were analyzed to exhibit a good fit between the modeled and observed energy spectral densities. In VLF range the energy spectral density of the TGF source current moment is found to be dominated by the contribution of secondary low-energy electrons and independent of the relativistic electrons which play their role in low-frequency (LF) range. Additional spectral modulation by the multiplicity of TGF peaks was found and demonstrated a good fit for two TGFs whose VLF sferics consist of two overlapping pulses each. The number of seeding pulses in TGF defines the spectral shape in VLF range, which allows to retrieve this number from VLF sferics, assuming they were radiated by TGFs. For two events it was found that the number of seeding pulses is small, of the order of 10. For the rest of the events the lower boundary of the number of seeding pulses was found to be between 10 to 103.
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Affiliation(s)
- Andrew Mezentsev
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - Nikolai Lehtinen
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - Nikolai Østgaard
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | | | - Steven A. Cummer
- Electrical and Computer Engineering DepartmentDuke UniversityDurhamNCUSA
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32
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Photonuclear reactions triggered by lightning discharge. Nature 2017; 551:481-484. [DOI: 10.1038/nature24630] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 10/10/2017] [Indexed: 11/09/2022]
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Köhn C, Chanrion O, Neubert T. Electron acceleration during streamer collisions in air. GEOPHYSICAL RESEARCH LETTERS 2017; 44:2604-2613. [PMID: 28503005 PMCID: PMC5405581 DOI: 10.1002/2016gl072216] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 02/25/2017] [Accepted: 02/28/2017] [Indexed: 06/07/2023]
Abstract
High-voltage laboratory experiments show that discharges in air, generated over a gap of one meter with maximal voltage of 1 MV, may produce X-rays with photon energies up to 1 MeV. It has been suggested that the photons are bremsstrahlung from electrons accelerated by the impulsive, enhanced field during collisions of negative and a positive streamers. To explore this process, we have conducted the first self-consistent particle simulations of streamer encounters. Our simulation model is a 2-D, cylindrically symmetric, particle-in-cell code tracing the electron dynamics and solving the space charge fields, with a Monte Carlo scheme accounting for collisions and ionization. We present the electron density, the electric field, and the velocity distribution as functions of space and time. Assuming a background electric field 1.5 times the breakdown field, we find that the electron density reaches 2·1021 m-3, the size of the encounter region is ∼3·10-12 m3 and that the field enhances to ∼9 times the breakdown field during ∼10-11 s. We further find that the radial component becomes comparable to the parallel component, which together with angular scattering leads to an almost isotropic distribution of electrons. This is consistent with laboratory observations that X-rays are emitted isotropically. However, the maximum energy of electrons reached in the simulation is ∼600 eV, which is well below the energies required to explain observations. The reason is that the encounter region is small in size and duration. For the photon energies observed, the field must be enhanced in a larger region and/or for a longer time.
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Affiliation(s)
- Christoph Köhn
- DTU Space, National Space InstituteTechnical University of DenmarkKongens LyngbyDenmark
| | - Olivier Chanrion
- DTU Space, National Space InstituteTechnical University of DenmarkKongens LyngbyDenmark
| | - Torsten Neubert
- DTU Space, National Space InstituteTechnical University of DenmarkKongens LyngbyDenmark
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34
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Köhn C, Diniz G, Harakeh MN. Production mechanisms of leptons, photons, and hadrons and their possible feedback close to lightning leaders. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2017; 122:1365-1383. [PMID: 28357174 PMCID: PMC5349290 DOI: 10.1002/2016jd025445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 01/02/2017] [Accepted: 01/03/2017] [Indexed: 06/06/2023]
Abstract
It has been discussed that lightning flashes emit high-energy electrons, positrons, photons, and neutrons with single energies of several tens of MeV. In the first part of this paper we study the absorption of neutron beams in the atmosphere. We initiate neutron beams of initial energies of 350 keV, 10 MeV, and 20 MeV at source altitudes of 4 km and 16 km upward and downward and see that in all these cases neutrons reach ground altitudes and that the cross-section areas extend to several km2. We estimate that for terrestrial gamma-ray flashes approximately between 10 and 2000 neutrons per ms and m2 are possibly detectable at ground, at 6 km, or at 500 km altitude. In the second part of the paper we discuss a feedback model involving the generation and motion of electrons, positrons, neutrons, protons, and photons close to the vicinity of lightning leaders. In contrast to other feedback models, we do not consider large-scale thundercloud fields but enhanced fields of lightning leaders. We launch different photon and electron beams upward at 4 km altitude. We present the spatial and energy distribution of leptons, hadrons, and photons after different times and see that leptons, hadrons, and photons with energies of at least 40 MeV are produced. Because of their high rest mass hadrons are measurable on a longer time scale than leptons and photons. The feedback mechanism together with the field enhancement by lightning leaders yields particle energies even above 40 MeV measurable at satellite altitudes.
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Affiliation(s)
- Christoph Köhn
- DTU Space, National Space InstituteTechnical University of DenmarkLyngbyDenmark
- Center for Mathematics and Computer ScienceCWIAmsterdamNetherlands
| | - Gabriel Diniz
- Instituto Nacional de Pesquisas EspaciaisSão José dos CamposBrazil
- Instituto de FísicaUniversidade de BrasíliaBrasíliaBrazil
| | - Muhsin N. Harakeh
- KVI‐Center for Advanced Radiation TechnologyUniversity of GroningenGroningenNetherlands
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35
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Mezentsev A, Østgaard N, Gjesteland T, Albrechtsen K, Lehtinen N, Marisaldi M, Smith D, Cummer S. Radio emissions from double RHESSI TGFs. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2016; 121:8006-8022. [PMID: 27774368 PMCID: PMC5054822 DOI: 10.1002/2016jd025111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 06/06/2023]
Abstract
A detailed analysis of Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) terrestrial gamma ray flashes (TGFs) is performed in association with World Wide Lightning Location Network (WWLLN) sources and very low frequency (VLF) sferics recorded at Duke University. RHESSI clock offset is evaluated and found to experience changes on the 5 August 2005 and 21 October 2013, based on the analysis of TGF-WWLLN matches. The clock offsets were found for all three periods of observations with standard deviations less than 100 μs. This result opens the possibility for the precise comparative analyses of RHESSI TGFs with the other types of data (WWLLN, radio measurements, etc.) In case of multiple-peak TGFs, WWLLN detections are observed to be simultaneous with the last TGF peak for all 16 cases of multipeak RHESSI TGFs simultaneous with WWLLN sources. VLF magnetic field sferics were recorded for two of these 16 events at Duke University. These radio measurements also attribute VLF sferics to the second peak of the double TGFs, exhibiting no detectable radio emission during the first TGF peak. Possible scenarios explaining these observations are proposed. Double (multipeak) TGFs could help to distinguish between the VLF radio emission radiated by the recoil currents in the +IC leader channel and the VLF emission from the TGF producing electrons.
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Affiliation(s)
- Andrew Mezentsev
- Birkeland Centre for Space Science, Department of Physics and Technology University of Bergen Bergen Norway
| | - Nikolai Østgaard
- Birkeland Centre for Space Science, Department of Physics and Technology University of Bergen Bergen Norway
| | - Thomas Gjesteland
- Birkeland Centre for Space Science, Department of Physics and Technology University of Bergen Bergen Norway; Department of Engineering Sciences University of Agder Grimstad Norway
| | - Kjetil Albrechtsen
- Birkeland Centre for Space Science, Department of Physics and Technology University of Bergen Bergen Norway
| | - Nikolai Lehtinen
- Birkeland Centre for Space Science, Department of Physics and Technology University of Bergen Bergen Norway
| | - Martino Marisaldi
- Birkeland Centre for Space Science, Department of Physics and Technology University of Bergen Bergen Norway; INAF-IASF National Institute for Astrophysics Bologna Italy
| | - David Smith
- Department of Physics, Santa Cruz Institute for Particle Physics University of California Santa Cruz California USA
| | - Steven Cummer
- Electrical and Computer Engineering Department Duke University Durham North Carolina USA
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36
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Østgaard N, Carlson BE, Nisi RS, Gjesteland T, Grøndahl Ø, Skeltved A, Lehtinen NG, Mezentsev A, Marisaldi M, Kochkin P. Relativistic electrons from sparks in the laboratory. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2016; 121:2939-2954. [PMID: 27840781 PMCID: PMC5080862 DOI: 10.1002/2015jd024394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 02/22/2016] [Accepted: 02/24/2016] [Indexed: 06/06/2023]
Abstract
Discharge experiments were carried out at the Eindhoven University of Technology in 2013. The experimental setup was designed to search for electrons produced in meter-scale sparks using a 1 MV Marx generator. Negative voltage was applied to the high voltage (HV) electrode. Five thin (1 mm) plastic detectors (5 cm2 each) were distributed in various configurations close to the spark gap. Earlier studies have shown (for HV negative) that X-rays are produced when a cloud of streamers is developed 30-60 cm from the negative electrode. This indicates that the electrons producing the X-rays are also accelerated at this location, that could be in the strong electric field from counterstreamers of opposite polarity. Comparing our measurements with modeling results, we find that ∼300 keV electrons produced about 30-60 cm from the negative electrode are the most likely source of our measurements. A statistical analysis of expected detection of photon bursts by these fiber detectors indicates that only 20%-45% of the detected bursts could be from soft (∼10 keV) photons, which further supports that the majority of detected bursts are produced by relativistic electrons.
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Affiliation(s)
- N. Østgaard
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - B. E. Carlson
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
- Department of PhysicsCarthage CollegeKenoshaWisconsinUSA
| | - R. S. Nisi
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - T. Gjesteland
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - Ø. Grøndahl
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - A. Skeltved
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - N. G. Lehtinen
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - A. Mezentsev
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - M. Marisaldi
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
| | - P. Kochkin
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
- Department of Electric EngineeringTechnische Iniversiteit EindhovenEindhovenNetherlands
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37
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Gjesteland T, Østgaard N, Laviola S, Miglietta MM, Arnone E, Marisaldi M, Fuschino F, Collier AB, Fabró F, Montanya J. Observation of intrinsically bright terrestrial gamma ray flashes from the Mediterranean basin. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2015; 120:12143-12156. [PMID: 27867780 PMCID: PMC5102168 DOI: 10.1002/2015jd023704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 10/12/2015] [Accepted: 11/11/2015] [Indexed: 06/06/2023]
Abstract
We present three terrestrial gamma ray flashes (TGFs) observed over the Mediterranean basin by the Reuven Ramaty High Energy Solar Spectroscope Imager (RHESSI) satellite. Since the occurrence of these events in the Mediterranean region is quite rare, the characterization of the events was optimized by combining different approaches in order to better define the cloud of origin. The TGFs on 7 November 2004 and 16 October 2006 came from clouds with cloud top higher than 10-12 km where often a strong penetration into the stratosphere is found. This kind of cloud is usually associated with heavy precipitation and intense lightning activity. Nevertheless, the analysis of the cloud type based on satellite retrievals shows that the TGF on 27 May 2004 was produced by an unusual shallow convection. This result appears to be supported by the model simulation of the particle distribution and phase in the upper troposphere. The TGF on 7 November 2004 is among the brightest ever measured by RHESSI. The analysis of the energy spectrum of this event is consistent with a production altitude ≤12 km, which is in the upper part of the cloud, as found by the meteorological analysis of the TGF-producing thunderstorm. This event must be unusually bright at the source in order to produce such a strong signal in RHESSI. We estimate that this TGF must contain ∼3 × 1018 initial photons with energy >1 MeV. This is 1 order of magnitude brighter than earlier estimations of an average RHESSI TGF.
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Affiliation(s)
- T. Gjesteland
- Department of Engineering SciencesUniversity of AgderGrimstadNorway
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | - N. Østgaard
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
| | | | | | | | - M. Marisaldi
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenBergenNorway
- INAF‐IASF BolognaBolognaItaly
| | | | - A. B. Collier
- School of Chemistry and PhysicsUniversity of KwaZulu-NatalDurbanSouth Africa
| | - F. Fabró
- Department of Electrical EngineeringPolytechnical University of CataloniaBarcelonaSpain
| | - J. Montanya
- Department of Electrical EngineeringPolytechnical University of CataloniaBarcelonaSpain
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38
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Marisaldi M, Argan A, Ursi A, Gjesteland T, Fuschino F, Labanti C, Galli M, Tavani M, Pittori C, Verrecchia F, D'Amico F, Østgaard N, Mereghetti S, Campana R, Cattaneo P, Bulgarelli A, Colafrancesco S, Dietrich S, Longo F, Gianotti F, Giommi P, Rappoldi A, Trifoglio M, Trois A. Enhanced detection of terrestrial gamma-ray flashes by AGILE. GEOPHYSICAL RESEARCH LETTERS 2015; 42:9481-9487. [PMID: 27773951 PMCID: PMC5054821 DOI: 10.1002/2015gl066100] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/16/2015] [Accepted: 10/19/2015] [Indexed: 06/06/2023]
Abstract
At the end of March 2015 the onboard software configuration of the Astrorivelatore Gamma a Immagini Leggero (AGILE) satellite was modified in order to disable the veto signal of the anticoincidence shield for the minicalorimeter instrument. The motivation for such a change was the understanding that the dead time induced by the anticoincidence prevented the detection of a large fraction of Terrestrial Gamma-Ray Flashes (TGFs). The configuration change was highly successful resulting in an increase of one order of magnitude in TGF detection rate. As expected, the largest fraction of the new events has short duration (<100 μs), and part of them has simultaneous association with lightning sferics detected by the World Wide Lightning Location Network. The new configuration provides the largest TGF detection rate surface density (TGFs/km2/yr) to date, opening prospects for improved correlation studies with lightning and atmospheric parameters on short spatial and temporal scales along the equatorial region.
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Affiliation(s)
- M. Marisaldi
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenNorway
| | | | - A. Ursi
- INAF‐IAPS RomaRomeItaly
- Dipartimento di FisicaUniversità Tor VergataRomeItaly
| | - T. Gjesteland
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenNorway
- Department of Engineering SciencesUniversity of AgderNorway
| | - F. Fuschino
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
- Dipartimento di Fisica e AstronomiaUniversità di BolognaBolognaItaly
| | - C. Labanti
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
| | | | - M. Tavani
- INAF‐IAPS RomaRomeItaly
- Dipartimento di FisicaUniversità Tor VergataRomeItaly
| | - C. Pittori
- ASI Science Data CenterRomeItaly
- INAF‐OARMonteporzio CatoneRomeItaly
| | - F. Verrecchia
- ASI Science Data CenterRomeItaly
- INAF‐OARMonteporzio CatoneRomeItaly
| | | | - N. Østgaard
- Birkeland Centre for Space Science, Department of Physics and TechnologyUniversity of BergenNorway
| | | | - R. Campana
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
| | | | - A. Bulgarelli
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
| | - S. Colafrancesco
- INAF‐OARMonteporzio CatoneRomeItaly
- School of PhysicsUniversity of the WitwatersrandJohannesburgSouth Africa
| | | | - F. Longo
- Dipartimento di FisicaUniversità di TriesteTriesteItaly
- INFN TriesteTriesteItaly
| | - F. Gianotti
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
| | | | | | - M. Trifoglio
- INAF‐IASFNational Institute for AstrophysicsBolognaItaly
| | - A. Trois
- INAF‐Osservatorio Astronomico di CagliariCapoterraItaly
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Kulkarni SR, Ofek EO, Neill JD, Zheng Z, Juric M. GIANT SPARKS AT COSMOLOGICAL DISTANCES? ACTA ACUST UNITED AC 2014. [DOI: 10.1088/0004-637x/797/1/70] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Skeltved AB, Østgaard N, Carlson B, Gjesteland T, Celestin S. Modeling the relativistic runaway electron avalanche and the feedback mechanism with GEANT4. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2014; 119:9174-9191. [PMID: 26167437 PMCID: PMC4497459 DOI: 10.1002/2014ja020504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 10/12/2014] [Indexed: 06/04/2023]
Abstract
UNLABELLED This paper presents the first study that uses the GEometry ANd Tracking 4 (GEANT4) toolkit to do quantitative comparisons with other modeling results related to the production of terrestrial gamma ray flashes and high-energy particle emission from thunderstorms. We will study the relativistic runaway electron avalanche (RREA) and the relativistic feedback process, as well as the production of bremsstrahlung photons from runaway electrons. The Monte Carlo simulations take into account the effects of electron ionization, electron by electron (Møller), and electron by positron (Bhabha) scattering as well as the bremsstrahlung process and pair production, in the 250 eV to 100 GeV energy range. Our results indicate that the multiplication of electrons during the development of RREAs and under the influence of feedback are consistent with previous estimates. This is important to validate GEANT4 as a tool to model RREAs and feedback in homogeneous electric fields. We also determine the ratio of bremsstrahlung photons to energetic electrons Nγ /Ne . We then show that the ratio has a dependence on the electric field, which can be expressed by the avalanche time τ(E) and the bremsstrahlung coefficient α(ε). In addition, we present comparisons of GEANT4 simulations performed with a "standard" and a "low-energy" physics list both validated in the 1 keV to 100 GeV energy range. This comparison shows that the choice of physics list used in GEANT4 simulations has a significant effect on the results. KEY POINTS Testing the feedback mechanism with GEANT4Validating the GEANT4 programming toolkitStudy the ratio of bremsstrahlung photons to electrons at TGF source altitude.
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Affiliation(s)
- Alexander Broberg Skeltved
- Birkeland Centre for Space Science, Institute of Physics and Technology, University of Bergen Bergen, Norway
| | - Nikolai Østgaard
- Birkeland Centre for Space Science, Institute of Physics and Technology, University of Bergen Bergen, Norway
| | - Brant Carlson
- Birkeland Centre for Space Science, Institute of Physics and Technology, University of Bergen Bergen, Norway ; Physics and Astronomy, Carthage College Kenosha, Wisconsin, USA
| | - Thomas Gjesteland
- Birkeland Centre for Space Science, Institute of Physics and Technology, University of Bergen Bergen, Norway
| | - Sebastien Celestin
- Laboratory of Physics and Chemistry of the Environment and Space, University of Orleans, CNRS Orleans, France
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Nisi RS, Østgaard N, Gjesteland T, Collier AB. An altitude and distance correction to the source fluence distribution of TGFs. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2014; 119:8698-8704. [PMID: 26167434 PMCID: PMC4497453 DOI: 10.1002/2014ja019817] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 09/08/2014] [Indexed: 06/04/2023]
Abstract
The source fluence distribution of terrestrial gamma ray flashes (TGFs) has been extensively discussed in recent years, but few have considered how the TGF fluence distribution at the source, as estimated from satellite measurements, depends on the distance from satellite foot point and assumed production altitude. As the absorption of the TGF photons increases significantly with lower source altitude and larger distance between the source and the observing satellite, these might be important factors. We have addressed the issue by using the tropopause pressure distribution as an approximation of the TGF production altitude distribution and World Wide Lightning Location Network spheric measurements to determine the distance. The study is made possible by the increased number of Ramaty High Energy Solar Spectroscopic Imager (RHESSI) TGFs found in the second catalog of the RHESSI data. One find is that the TGF/lightning ratio for the tropics probably has an annual variability due to an annual variability in the Dobson-Brewer circulation. The main result is an indication that the altitude distribution and distance should be considered when investigating the source fluence distribution of TGFs, as this leads to a softening of the inferred distribution of source brightness.
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Affiliation(s)
- R S Nisi
- Department of Physics and Technology, University of BergenBergen, Norway
- Birkeland Center for Space ScienceBergen, Norway
| | - N Østgaard
- Department of Physics and Technology, University of BergenBergen, Norway
- Birkeland Center for Space ScienceBergen, Norway
| | - T Gjesteland
- Department of Physics and Technology, University of BergenBergen, Norway
- Birkeland Center for Space ScienceBergen, Norway
| | - A B Collier
- School of Chemistry and Physics, University of KwaZulu-NatalDurban, South Africa
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42
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Luque A. Relativistic runaway ionization fronts. PHYSICAL REVIEW LETTERS 2014; 112:045003. [PMID: 24580462 DOI: 10.1103/physrevlett.112.045003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Indexed: 06/03/2023]
Abstract
We investigate the first example of self-consistent impact ionization fronts propagating at relativistic speeds and involving interacting, high-energy electrons. These fronts, which we name relativistic runaway ionization fronts, show remarkable features such as a bulk speed within less than one percent of the speed of light and the stochastic selection of high-energy electrons for further acceleration, which leads to a power-law distribution of particle energies. A simplified model explains this selection in terms of the overrun of Coulomb-scattered electrons. Appearing as the electromagnetic interaction between electrons saturates the exponential growth of a relativistic runaway electron avalanche, relativistic runaway ionization fronts may occur in conjunction with terrestrial gamma-ray flashes and thus explain recent observations of long, power-law tails in the terrestrial gamma-ray flash energy spectrum.
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Affiliation(s)
- A Luque
- Instituto de Astrofísica de Andalucía, IAA-CSIC, P.O. Box 3004, 18080 Granada, Spain
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43
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Boeck WL, Vaughan OH, Blakeslee RJ, Vonnegut B, Brook M, McKune J. Observations of lightning in the stratosphere. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/94jd02432] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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44
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Dwyer JR, Babich LP. Low-energy electron production by relativistic runaway electron avalanches in air. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011ja016494] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Joseph R. Dwyer
- Department of Physics and Space Sciences; Florida Institute of Technology; Melbourne Florida USA
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Levan AJ, Tanvir NR, Cenko SB, Perley DA, Wiersema K, Bloom JS, Fruchter AS, Postigo ADU, O’Brien PT, Butler N, van der Horst AJ, Leloudas G, Morgan AN, Misra K, Bower GC, Farihi J, Tunnicliffe RL, Modjaz M, Silverman JM, Hjorth J, Thöne C, Cucchiara A, Cerón JMC, Castro-Tirado AJ, Arnold JA, Bremer M, Brodie JP, Carroll T, Cooper MC, Curran PA, Cutri RM, Ehle J, Forbes D, Fynbo J, Gorosabel J, Graham J, Hoffman DI, Guziy S, Jakobsson P, Kamble A, Kerr T, Kasliwal MM, Kouveliotou C, Kocevski D, Law NM, Nugent PE, Ofek EO, Poznanski D, Quimby RM, Rol E, Romanowsky AJ, Sánchez-Ramírez R, Schulze S, Singh N, van Spaandonk L, Starling RLC, Strom RG, Tello JC, Vaduvescu O, Wheatley PJ, Wijers RAMJ, Winters JM, Xu D. An Extremely Luminous Panchromatic Outburst from the Nucleus of a Distant Galaxy. Science 2011; 333:199-202. [PMID: 21680811 DOI: 10.1126/science.1207143] [Citation(s) in RCA: 258] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- A. J. Levan
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - N. R. Tanvir
- Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | - S. B. Cenko
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - D. A. Perley
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - K. Wiersema
- Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | - J. S. Bloom
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - A. S. Fruchter
- Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
| | - A. de Ugarte Postigo
- Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - P. T. O’Brien
- Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | - N. Butler
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - A. J. van der Horst
- Universities Space Research Association, National Space Science and Technology Center, 320 Sparkman Drive, Huntsville, AL 35805, USA
| | - G. Leloudas
- Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - A. N. Morgan
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - K. Misra
- Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
| | - G. C. Bower
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - J. Farihi
- Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | | | - M. Modjaz
- Columbia Astrophysics Laboratory, Columbia University, New York, NY 10024, USA
| | - J. M. Silverman
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - J. Hjorth
- Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - C. Thöne
- Instituto de Astrofísica de Andalucía–Consejo Superior de Investigaciones Científicas (IAA-CSIC), Glorieta de la Astronomía s/n, E-18008 Granada, Spain
| | - A. Cucchiara
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
| | - J. M. Castro Cerón
- Herschel Science Operations Centre, European Space Astronomy Centre, European Space Agency (ESA), Post Office Box 78, 28691 Villanueva de la Caada, Madrid, Spain
| | - A. J. Castro-Tirado
- Instituto de Astrofísica de Andalucía–Consejo Superior de Investigaciones Científicas (IAA-CSIC), Glorieta de la Astronomía s/n, E-18008 Granada, Spain
| | - J. A. Arnold
- University of California Observatories/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - M. Bremer
- Institut de RadioAstronomie Millimétrique, 300 rue de la Piscine, Domaine Universitaire, 38406 Saint Martin d’Hères, France
| | - J. P. Brodie
- University of California Observatories/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - T. Carroll
- Joint Astronomy center, 660 North A’ohoku Place, University Park, Hilo, HI 96720, USA
| | - M. C. Cooper
- Center for Galaxy Evolution, University of California, Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697, USA
| | - P. A. Curran
- Astrophysique Interactions Multi-échelles, Commissariat à l’Énergie Atomique/Direction des Sciences de la Matière–CNRS, Irfu/Service d’Astrophysique, Centre de Saclay, Bâtiment 709, FR-91191 Gif-sur-Yvette Cedex, France
| | - R. M. Cutri
- Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125, USA
| | - J. Ehle
- Joint Astronomy center, 660 North A’ohoku Place, University Park, Hilo, HI 96720, USA
| | - D. Forbes
- Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn VIC 3122 Australia
| | - J. Fynbo
- Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - J. Gorosabel
- Instituto de Astrofísica de Andalucía–Consejo Superior de Investigaciones Científicas (IAA-CSIC), Glorieta de la Astronomía s/n, E-18008 Granada, Spain
| | - J. Graham
- Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
| | - D. I. Hoffman
- Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125, USA
| | - S. Guziy
- Instituto de Astrofísica de Andalucía–Consejo Superior de Investigaciones Científicas (IAA-CSIC), Glorieta de la Astronomía s/n, E-18008 Granada, Spain
| | - P. Jakobsson
- Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhaga 5 IS-107 Reykjavik, Iceland
| | - A. Kamble
- Center for Gravitation and Cosmology, University of Wisconsin-Milwaukee, 1900 East Kenwood Boulevard, Milwaukee,WI 53211, USA
| | - T. Kerr
- Joint Astronomy center, 660 North A’ohoku Place, University Park, Hilo, HI 96720, USA
| | - M. M. Kasliwal
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA
| | - C. Kouveliotou
- Space Science Office, VP62, NASA/Marshall Space Flight Center Huntsville, AL 35812, USA
| | - D. Kocevski
- University of California Observatories/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - N. M. Law
- Dunlap Institute for Astronomy and Astrophysics, University of Toronto, Toronto, M5S 3H4 Ontario, Canada
| | - P. E. Nugent
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
- Computational Cosmology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - E. O. Ofek
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA
| | - D. Poznanski
- Department of Astronomy, University of California, Berkeley, CA 94720–3411, USA
- Computational Cosmology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - R. M. Quimby
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA
| | - E. Rol
- Astronomical Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - A. J. Romanowsky
- University of California Observatories/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - R. Sánchez-Ramírez
- Instituto de Astrofísica de Andalucía–Consejo Superior de Investigaciones Científicas (IAA-CSIC), Glorieta de la Astronomía s/n, E-18008 Granada, Spain
| | - S. Schulze
- Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhaga 5 IS-107 Reykjavik, Iceland
| | - N. Singh
- University of California Observatories/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
- Centre for Astronomy, National University of Ireland, Galway, Ireland
| | - L. van Spaandonk
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
- Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Hatfield AL10 9AB, UK
| | - R. L. C. Starling
- Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | - R. G. Strom
- Astronomical Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
- Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, 7990 AA Dwingeloo, Netherlands
| | - J. C. Tello
- Instituto de Astrofísica de Andalucía–Consejo Superior de Investigaciones Científicas (IAA-CSIC), Glorieta de la Astronomía s/n, E-18008 Granada, Spain
| | - O. Vaduvescu
- Isaac Newton Group of Telescopes, Apartado de correos 321 E-38700, Santa Cruz de la Palma, Canary Islands, Spain
| | - P. J. Wheatley
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - R. A. M. J. Wijers
- Astronomical Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - J. M. Winters
- Institut de RadioAstronomie Millimétrique, 300 rue de la Piscine, Domaine Universitaire, 38406 Saint Martin d’Hères, France
| | - D. Xu
- Benoziyo Center for Astrophysics, Faculty of Physics, Weizmann Institute of Science, Rehovot, 76100, Israel
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Lu G, Cummer SA, Li J, Han F, Smith DM, Grefenstette BW. Characteristics of broadband lightning emissions associated with terrestrial gamma ray flashes. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010ja016141] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Gaopeng Lu
- Electrical and Computer Engineering Department; Duke University; Durham North Carolina USA
| | - Steven A. Cummer
- Electrical and Computer Engineering Department; Duke University; Durham North Carolina USA
| | - Jingbo Li
- Electrical and Computer Engineering Department; Duke University; Durham North Carolina USA
| | - Feng Han
- Electrical and Computer Engineering Department; Duke University; Durham North Carolina USA
| | - David M. Smith
- Department of Physics, Santa Cruz Institute for Particle Physics; University of California; Santa Cruz California USA
| | - Brian W. Grefenstette
- Space Radiation Laboratory; California Institute of Technology; Pasadena California USA
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Celestin S, Pasko VP. Energy and fluxes of thermal runaway electrons produced by exponential growth of streamers during the stepping of lightning leaders and in transient luminous events. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010ja016260] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sebastien Celestin
- Department of Electrical Engineering, Communications and Space Sciences Laboratory; Pennsylvania State University; University Park Pennsylvania USA
| | - Victor P. Pasko
- Department of Electrical Engineering, Communications and Space Sciences Laboratory; Pennsylvania State University; University Park Pennsylvania USA
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Tavani M, Marisaldi M, Labanti C, Fuschino F, Argan A, Trois A, Giommi P, Colafrancesco S, Pittori C, Palma F, Trifoglio M, Gianotti F, Bulgarelli A, Vittorini V, Verrecchia F, Salotti L, Barbiellini G, Caraveo P, Cattaneo PW, Chen A, Contessi T, Costa E, D'Ammando F, Del Monte E, De Paris G, Di Cocco G, Di Persio G, Donnarumma I, Evangelista Y, Feroci M, Ferrari A, Galli M, Giuliani A, Giusti M, Lapshov I, Lazzarotto F, Lipari P, Longo F, Mereghetti S, Morelli E, Moretti E, Morselli A, Pacciani L, Pellizzoni A, Perotti F, Piano G, Picozza P, Pilia M, Pucella G, Prest M, Rapisarda M, Rappoldi A, Rossi E, Rubini A, Sabatini S, Scalise E, Soffitta P, Striani E, Vallazza E, Vercellone S, Zambra A, Zanello D. Terrestrial gamma-ray flashes as powerful particle accelerators. PHYSICAL REVIEW LETTERS 2011; 106:018501. [PMID: 21231775 DOI: 10.1103/physrevlett.106.018501] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Indexed: 05/30/2023]
Abstract
Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x rays and γ rays lasting a few milliseconds or less. We present in this Letter new TGF timing and spectral data based on the observations of the Italian Space Agency AGILE satellite. We determine that the TGF emission above 10 MeV has a significant power-law spectral component reaching energies up to 100 MeV. These results challenge TGF theoretical models based on runaway electron acceleration. The TGF discharge electric field accelerates particles over the large distances for which maximal voltages of hundreds of megavolts can be established. The combination of huge potentials and large electric fields in TGFs can efficiently accelerate particles in large numbers, and we reconsider here the photon spectrum and the neutron production by photonuclear reactions in the atmosphere.
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Affiliation(s)
- M Tavani
- INAF-IASF Roma, via del Fosso del Cavaliere 100, I-00133 Roma, Italy
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Said RK, Inan US, Cummins KL. Long-range lightning geolocation using a VLF radio atmospheric waveform bank. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd013863] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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