Terrestrial Gamma-ray Flashes Can Be Detected with Radio Measurements of Energetic In-cloud Pulses during Thunderstorms

ASIM has now observed several hundreds of TGFs since the launch in 2018. Highlights and new science from the first ten months of observations were presented in &#216;stgaard et al. (2019) paper. In this presentation we will present observational highlights from the last 1.5 year, when the relative timing accuracy between the TGF observations and the optical measurements is +/- 5 us (compared to +/- 80 us before march 2019). This includes many more simultaneous TGF and Elve observations, high flux TGFs, double TGFs simultaneous with double optical pulses and many TGFs with good radio measurements.&#160; ASIM has also observed several Gamma Ray Bursts.&#160;

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Is there a non-stationary γ-ray emission zone 42 pc from the 3C 279 core?

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834401 ◽

2019 ◽

Vol 630 ◽

pp. A56 ◽

Cited By ~ 3

Author(s):

V. M. Patiño-Álvarez ◽

S. A. Dzib ◽

A. Lobanov ◽

V. Chavushyan

Keyword(s):

Gamma Rays ◽

Gamma Ray ◽

Rank Correlation ◽

Spearman Rank Correlation ◽

Superluminal Velocity ◽

Γ Ray ◽

Gamma Ray Emission ◽

Radio Measurements ◽

The Relationship ◽

Region Feature

We investigate the relationship between the variable gamma-ray emission and jet properties in the blazar 3C 279 by combining the Fermi-LAT data spanning a period of eight years and concurrent radio measurements made at multiple epochs with VLBA at 15 and 43 GHz within the MOJAVE and VLBA-BU monitoring programmes. The aim of this paper is to compare the flux variability of the different components found in the VLBA observations, to the variability in the gamma-rays. This analysis helps us to investigate whether any of the jet components can be associated with the gamma-ray variability. Through Spearman rank correlation we found that the gamma-ray variability is correlated with a particular region (feature B in the MOJAVE images) downstream from the observed base (core) of the jet. This jet component is therefore a likely location where an important fraction of the variable gamma-ray emission is produced. We also calculated the average proper motion of the component with respect to the VLBA core and found that it moves at an apparent superluminal velocity of (3.70 ± 0.35)c, implying that one of the gamma-ray emission zones is not stationary. This jet component is also found between 6.86 mas and 8.68 mas, which translates to a distance from the radio core of at least 42 pc.

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Terrestrial Gamma‐ray Flashes Can Be Detected with Radio Measurements of Energetic In‐cloud Pulses during Thunderstorms

Geophysical Research Letters ◽

10.1029/2021gl093627 ◽

2021 ◽

Author(s):

Fanchao Lyu ◽

Steven A. Cummer ◽

Michael Briggs ◽

David M. Smith ◽

Bagrat Mailyan ◽

...

Keyword(s):

Gamma Ray ◽

Radio Measurements

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On the possible gamma-ray source in Cygnus

Symposium - International Astronomical Union ◽

10.1017/s0074180900101391 ◽

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.

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

International Astronomical Union Colloquium ◽

10.1017/s0252921100026208 ◽

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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