@Article{DinizRutEbeFerSão:2018:MoNeEm,
author = "Diniz, Gabriel Sousa and Rutjes, Casper and Ebert, Ute and
Ferreira, I. S. and S{\~a}o Sabbas, Eliah Fernanda de Maria
Tavares",
affiliation = "{Universidade de Bras{\'{\i}}lia (UnB)} and {Centrum Wiskunde
\& Informatica (CWI)} and {Centrum Wiskunde \& Informatica
(CWI)} and {Universidade de Bras{\'{\i}}lia (UnB)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)}",
title = "Modeling neutron emissions in high energy atmospheric phenomena",
journal = "Journal of Geophysical Research: Atmospheres",
year = "2018",
volume = "123",
number = "22",
pages = "12726--12737",
month = "Dec.",
abstract = "Neutron emissions with different durations have been observed
during thunderstorms. These neutrons can be produced by
microsecond to millisecond fast Terrestrial Gamma-ray Flashes
correlated with lightning, or by Gamma-ray Glows lasting several
seconds to minutes. In both cases, the neutrons are produced
through a photonuclear reaction of gamma rays in the energy range
of 10 to 30 MeV with nuclei of air molecules. Here we present
simulations of gamma-ray beams propagating downward from different
source altitudes. In our analysis the primary photons with
energies between 10 and 30 MeV are separated into four energy
intervals, each of 5 MeV width. From these data, arbitrary spectra
of primary photons and of their products can be composed. Our
results indicate that the neutrons are created essentially along
the trajectory of the primary photons and that they reach ground
within a transversal area of radius below 500 m. This lateral
spreading is dominated by neutron diffusion due to collisions with
air molecules. A secondary longer lasting photon pulse at sea
level is predicted as well by our simulations. We have introduced
this Terrestrial Gamma-ray Flash afterglow already in (Rutjes et
al. 2017,
https://doi-org.ez61.periodicos.capes.gov.br/10.1002/2017GL075552).
It is due to neutron capture by air molecules, and it has recently
been observed by Bowers et al. (2017,
https://doi-org.ez61.periodicos.capes.gov.br/10.1002/2017GL075071)
and Enoto et al. (2017,
https://doi-org.ez61.periodicos.capes.gov.br/10.1038/nature24630.",
doi = "10.1029/2018JD028962",
url = "http://dx.doi.org/10.1029/2018JD028962",
issn = "2169-8996 and 2169-897X",
language = "en",
targetfile = "diniz_modeling.pdf",
urlaccessdate = "04 maio 2024"
}