scholarly journals La verdad es hija del tiempo

2021 ◽  
Author(s):  
Horacio Torres-Sánchez
Keyword(s):  
Gamma Ray ◽  
Transient Luminous Events

Las descargas eléctricas atmosféricas que se generan entre las nubes y la ionosfera son fenómenos electromagnéticos que se vienen estudiando sistemáticamente a nivel mundial hace muy poco tiempo, cerca de 30 años. Su interés radica en las radiaciones de muy alta frecuencia (rayos gamma) que son muy diferentes a los rayos que hasta ahora se han estudiado en el rango de las radiofrecuencias. En este artículo se presentan los fenómenos denominados destellos de rayos gamma terrestres (Terrestrial Gamma-ray Flash, TGF) y eventos luminosos terrestres (transient luminous events, TLE), y se analiza el papel de los estudios que lleva a cabo en Colombia el grupo PAAS-UN y los beneficios que esta rigurosa y sistemática investigación representan para el futuro del conocimiento científico de los rayos en el país.

Lightning optical context associated with ASIM TGFs

2020 ◽  
Author(s):  
Andrey Mezentsev ◽  
Nikolai Østgaard ◽  
Martino Marisaldi ◽  
Pavlo Kochkin ◽  
Torsten Neubert ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Space Station ◽  
High Energy ◽  
Relative Timing ◽  
Science Data ◽  
Timing Accuracy ◽  
Transient Luminous Events ◽  
Imaging Array ◽  
Lightning Discharges ◽  
Energy Detectors

<p>Launched and installed at the International Space Station in April 2018, the Atmosphere-Space Interactions Monitor (ASIM) provides science data since June 2018. Suite of onboard instruments contains optical and high energy detectors payloads. Modular Multi-spectral Imaging Array (MMIA) includes three photometers (180-240 nm, 337 nm and 777.4 nm) sampling at 100 kHz, and two cameras (337 nm and 777.4 nm) sampling at 12 Hz. It allows for lightning and transient luminous events (TLEs) observations during the orbital eclipses. The Modular X- and Gamma-ray Sensor (MXGS) detects X- and Gamma-ray photons, and is dedicated to detection of Terrestrial Gamma-ray Flashes (TGFs). The mutual relative timing accuracy between MXGS and MMIA is as good as +/- 5 µs.</p><p> </p><p>TGFs are known to be associated with the +IC lightning discharges. ASIM provides a unique possibility for simultaneous observations of TGFs together with the underlying optical activity inside the thundercloud. In this contribution we summarize the almost two years of ASIM observations to make an overview of the various optical contexts accompanying the TGF production.</p>

scholarly journals SPRITE-SAT: a Micro Satellite for Scientific Observation of Transient Luminous Events and Terrestrial Gamma-Ray Flashes

2010 ◽  
Vol 8 (ists27) ◽  
pp. Tm_7-Tm_12 ◽  
Author(s):  
Kazuya YOSHIDA ◽  
Yukihiro TAKAHASHI ◽  
Yuji SAKAMOTO ◽  
Eriko UJIIE ◽  
Kei TAKIUCHI ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Scientific Observation ◽  
Transient Luminous Events

Scattering of lightning optical radiation by complex, inhomogeneous clouds

2020 ◽  
Author(s):  
Alejandro Luque Estepa ◽  
Francisco José Gordillo-Vázquez ◽  
Dongshuai Li ◽  
Alejandro Malagón-Romero ◽  
Sergio Soler ◽  
...  
Keyword(s):  
Optical Radiation ◽  
Multispectral Imaging ◽  
Gamma Ray ◽  
Space Station ◽  
Numerical Code ◽  
Transient Luminous Events ◽  
Spatially Resolved ◽  
Set Operations ◽  
Cloud Tops ◽  
Interpretation Of Satellite Images

<p>Lightning flashes emit intense optical radiation that can be detected from space. Several space missions work by observing this light in order to investigate lightning, thunderstorms, and other phenomena closely associated to them such as Transient Luminous Events (TLEs) and Terrestrial Gamma-ray Flashes (TGFs).</p><p>In its path towards a satellite-borne observing device, the optical radiation emitted by a flash is scattered many times by the droplets and ice crystals in the cloud. The detected signal is thus shaped by and contains information about the cloud geometry and composition. This is particularly relevant for instruments with a high spatial resolution such as the cameras in the Modular Multispectral Imaging Array (MMIA), which is part of the Atmosphere-Space Interactions Monitor (ASIM) currently onboard the International Space Station. These cameras provide images of lightning-illuminated cloud tops with a resolution of about 400 m.</p><p>We present a numerical code that can simulate light scattering in clouds with complex geometries and location-dependent droplet density and effective radius. The cloud geometry is specified by a number of elementary shapes (e.g. spheres and cylinders) that can be linearly deformed as well as combined by set operations such as unions, intersections and subtractions. The cloud composition can be specified by arbitrary functions. Designed to aid in the interpretation of satellite images, the code simulates spatially resolved observations from an arbitrary viewpoint. Some examples and applications of this tool will be discussed.</p>

ASIM TGFs with accompanying elves

2021 ◽  
Author(s):  
Ingrid Bjørge-Engeland ◽  
Nikolai Østgaard ◽  
Andrey Mezentsev ◽  
Torsten Neubert ◽  
Chris Alexander Skeie ◽  
...  
Keyword(s):  
Multispectral Imaging ◽  
Gamma Ray ◽  
Field Of View ◽  
Transient Luminous Events ◽  
Imaging Array ◽  
Using Data

<p><span>The Atmospheric Space Interactions Monitor (ASIM) was launched in 2018, and has since then observed Terrestrial Gamma-ray Flashes (TGFs) and Transient Luminous Events (TLEs). ASIM consists of the Modular X- and Gamma-ray Sensor (MXGS) and the Modular Multispectral Imaging Array (MMIA). Using data from both MXGS and MMIA, we investigate observations of TGFs (detected by MXGS) with accompanying elves (detected by MMIA). We study the optical signatures of the elves detected by a photometer of MMIA operating in the 180-230 nm band. Lightning sferics associated with these events have been detected by WWLLN and GLD360. Several TGFs have associated lightning sferics outside the field of view of MMIA, but due to the expanding rings of the elves we can still observe optical signatures from accompanying elves. Using GLD360 data we also study properties of the lightning strokes. </span></p>

ASIM - Fermi - AGILE simultaneous observation of Terrestrial Gamma-ray Flashes

2020 ◽  
Author(s):  
Martino Marisaldi ◽  
Andrey Mezentsev ◽  
David Sarria ◽  
Anders Lindanger ◽  
Nikolai Østgaard ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Space Station ◽  
Light Curves ◽  
Simultaneous Observation ◽  
Orbital Parameters ◽  
Location Data ◽  
Transient Luminous Events ◽  
The Earth ◽  
Production Models ◽  
Field Geometry

<p>The Atmosphere Space Interaction Monitor (ASIM) mission onboard the International Space Station is the first mission specifically dedicated to the observation of Terrestrial Gamma-ray Flashes (TGF) and Transient Luminous Events (TLE). ASIM, together with the Fermi and AGILE satellites, are the only three currently operating missions capable to detect TGFs from space. Depending on orbital parameters, pairs of these missions periodically get closer than few hundreds kilometers, observing the same region on the Earth surface for up to several tens of seconds. This offers the unique chance to observe the same TGF from two different viewing angles. Such observations allow to probe the TGF production geometry and possibly put constraints on production models and electric field geometry at the source.</p><p>Here we present four TGFs detected by ASIM and simultaneously detected by Fermi (three events) or AGILE (one event) in the period June 2018 - November 2019. We present location data, light curves, and possible constraints to emission geometry based on coupled observations and Monte Carlo simulations. </p>

On the possible gamma-ray source in Cygnus

1967 ◽  
Vol 31 ◽  
pp. 469-471
Author(s):  
J. G. Duthie ◽  
M. P. Savedoff ◽  
R. Cobb
Keyword(s):  
Gamma Rays ◽  
Gamma Ray ◽  
Right Ascension

A source of gamma rays has been found at right ascension 20h15m, declination +35°, with an uncertainty of 6° in each coordinate. Its flux is (1·5 ± 0·8) x 10-4photons cm-2sec-1at 100 MeV. Possible identifications are reviewed, but no conclusion is reached. The mechanism producing the radiation is also uncertain.

Solar Flare Energetic Neutral Emission Measurements in the Project Coronas-I

1994 ◽  
Vol 144 ◽  
pp. 635-639
Author(s):  
J. Baláž ◽  
A. V. Dmitriev ◽  
M. A. Kovalevskaya ◽  
K. Kudela ◽  
S. N. Kuznetsov ◽  
...  
Keyword(s):  
Solar Flare ◽  
Energy Range ◽  
Gamma Rays ◽  
Pulse Shape ◽  
Gamma Ray ◽  
Pulse Shape Discrimination ◽  
Shape Discrimination ◽  
Solar Neutron ◽  
Low Altitude

AbstractThe experiment SONG (SOlar Neutron and Gamma rays) for the low altitude satellite CORONAS-I is described. The instrument is capable to provide gamma-ray line and continuum detection in the energy range 0.1 – 100 MeV as well as detection of neutrons with energies above 30 MeV. As a by-product, the electrons in the range 11 – 108 MeV will be measured too. The pulse shape discrimination technique (PSD) is used.

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