@MastersThesis{Mendizabal:2014:EsEmAl,
author = "Mendizabal, Iver Ronald Winkelmann",
title = "Estudo de emiss{\~o}es de alta energia produzidas por campos
el{\'e}tricos de rel{\^a}mpagos e nuvens de tempestades",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2014",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2014-04-01",
keywords = "Emiss{\~o}es de alta energia, tempestades, testes
estat{\'{\i}}sticos, Observat{\'o}rio de Raios C{\'o}smicos
Pierre Auger, Lightning Imaging Sensor - LIS, High energy
emissions, thunderstorms, statistical tests, Pierre Auger Cosmic
Ray Observatory, Lightning Imaging Sensor - LIS.",
abstract = "Embora teorizada na d{\'e}cada de 1920, a emiss{\~a}o de
part{\'{\i}}culas e f{\'o}tons energ{\'e}ticos por nuvens de
tempestade e rel{\^a}mpagos vem sendo alvo de intenso estudo
apenas nas {\'u}ltimas d{\'e}cadas. Essa nova {\'a}rea de
pesquisa, denominada como F{\'{\i}}sica Atmosf{\'e}rica de Alta
Energia, ganhou grande interesse com a descoberta inicial de
flashes de raios gama com origem terrestre, registrados por um dos
instrumentos do sat{\'e}lite Observat{\'o}rio Compton de Raios
Gama (CGRO). Diversos estudos experimentais e te{\'o}ricos
revelaram muitas caracter{\'{\i}}sticas da origem e da
produ{\c{c}}{\~a}o desse fen{\^o}meno, o mais energ{\'e}tico
produzido em nosso planeta. Entretanto, existem quest{\~o}es
fundamentais que permanecem sem resposta. Uma delas {\'e} o
origem do campo el{\'e}trico capaz de acelerar el{\'e}trons que
possam emitir f{\'o}tons com energias de at{\'e} 100 \emph{Me
V}. Neste trabalho, pela primeira vez, explorou-se dados de
rel{\^a}mpago, coletados pelo Sensor Imageador de Rel{\^a}mpagos
(LIS) a bordo do sat{\'e}lite Miss{\~a}o de Medida da
Precipita{\c{c}}{\~a}o Tropical (TRMM), conjuntamente com dados
de part{\'{\i}}culas/f{\'o}tons de alta energia detectados no
solo pelos sensores do Observat{\'o}rio Pierre Auger, localizado
na Argentina, na procura de tais emiss{\~o}es. Utilizando cinco
anos de dados foi realizada uma an{\'a}lise preliminar procurando
coincid{\^e}ncias com uma diferen{\c{c}}a m{\'a}xima de
\$\pm\$100 \emph{MS}, resultando apenas 1,72\% dos dados do
LIS em coincid{\^e}ncia com os eventos registrados pelo Auger.
Foram implementados testes estat{\'{\i}}sticos para averiguar se
essa percentagem poderia ou n{\~a}o ser resultado de uma
associa{\c{c}}{\~a}o puramente aleat{\'o}ria. Os testes
mostraram que a probabilidade de encontrar coincid{\^e}ncias
espa{\c{c}}o-temporais aleat{\'o}rias {\'e} aproximadamente
tr{\^e}s vezes menor do que a percentagem encontrada. Para
aperfei{\c{c}}oar a an{\'a}lise, os Grupos foram agrupados em
Flashes utilizando-se os crit{\'e}rios tempo-espaciais do LIS,
assim o conjunto de dados foi reduzido em 209 Grupos e 209 eventos
T3, eventos que est{\~a}o compostos por 841 registros de tanques
individuais. Posteriormente foi analisado o tipo de tra{\c{c}}o
registro de cada tanque, separando-os entre tra{\c{c}}os
produzidos por part{\'{\i}}culas/f{\'o}tons (73,9\%) e
tra{\c{c}}os produzidos por emiss{\~o}es VHF dos rel{\^a}mpagos
(26,1\%). Do total de tanques com tra{\c{c}}o de emiss{\~o}es
VHF 96\% foram registradas a uma dist{\^a}ncia
\$\leq\$32\$\pm\$4 \emph{km} da localiza{\c{c}}{\~a}o dos
primeiros Grupos dos Flashes. Por outro lado, cinco tanques com
tra{\c{c}}o de part{\'{\i}}culas/f{\'o}tons foram registrados
a uma dist{\^a}ncia \$\leq\$4\$\pm\$ 4 \emph{km}. Uma
an{\'a}lise detalhada dos cinco tanques foi realizada devido a
duas raz{\~o}es: 1) uma an{\'a}lise comparativa entre
distribui{\c{c}}{\~o}es de diferen{\c{c}}as espaciais mostrou
que todos os registros de tanques com
\$\Delta\$\emph{s}\$\leq\$20 \emph{km} n{\~a}o eram bem
explicados; e 2) a restri{\c{c}}{\~a}o espacial, reportada na
literatura, que estabelece o alcance m{\'a}ximo das
part{\'{\i}}culas emitidas pelas nuvens de tempestade em
\$\sim\$500 m. A an{\'a}lise detalhada dos cinco tanques
mostrou que a taxa de detec{\c{c}}{\~a}o de
part{\'{\i}}culas/f{\'o}tons emitidas pelo primeiro Grupo dos
Flashes foi de 7,8 x \$10^{-5}\$. A dura{\c{c}}{\~a}o dos
registros variou entre 0,27\$\mu\$\emph{s} e
0,50\$\mu\$\emph{s} e sua energia ficou entre 489,4
\emph{MeV} e 2493,2 \emph{MeV}. O \$\Delta\$\emph{t} entre
eles e os Flashes associados variou entre -31\$\pm\$26
\$\mu\$\emph{s} e 11\$\pm\$26 \$\mu\$\emph{s} e em um
dos casos foi poss{\'{\i}}vel estabelecer que o Grupo aconteceu
antes do registro no tanque. ABSTRACT: Theorized in the 1920s,
emission of particles and energetic photons by thunderclouds and
lightning has beem the subject of intense study within the last
couple of decades. This new area of research, called High-Energy
Atmospheric Physics, became subject of great interest with the
accidental discovery of gamma-ray burst of terrestrial origin, as
registered by one of the instruments of the satellite Compton
Gamma- Ray Observatory (CGRO). Several experimental and
theoretical studies have revealed many of the features related to
the origin and production of this phenomenon, the most energetic
produced in our planet. However, there are fundamental questions
that remain unanswered. One is the origin of the electric field
capable of accelerating electrons that can emit photons with
energies up to 100 \emph{M eV}. In this work, the data of the
Lightning Imaging Sensor (LIS), onboard the Tropical Rainfall
Measurement Mission (TRMM) satellite, was explored for the first
time in combination with the high energy particlejphoton data of
the tank detectors of the Pierre Auger Observatory, located in
Argentina, in seeking of such emissions. Using five years of data,
a preliminary analysis was performed looking for coincidences with
a maximum difference of \$\pm\$100 \emph{ms}, resulting in
only 1.72\% of the LIS data in coincidence with the events
recorded by Auger. Statistical tests were implemented to determine
whether this percentage could result from a purely random
association or noto The tests showed that the probability of
finding space-time random coincidences is approximately three
times less than the percentage found. In order to refine the
analysis, we grouped the Group data into Flashes using 11S
space-time criteria, such that the resulting data set was reduced
to 209 Groups and 209 events T3, events that are composed of 841
individual detector tanks records. Subsequently we analyzed the
type of trace recorded in each tank, classifying them into traces
produced by particlesjphotons (73.9\%) and traces produced by VHF
emissions (26.1\%). Of the total of the tanks with VHF emission
traces 96\% were recorded at a distance \$\leq\$32\$\pm\$4
\emph{km} from the location of the first Group of the Flash. On
the other hand, five tanks with particlesjphotons traces were
recorded at a distance \$\leq\$4\$\pm\$4 km. A detailed
analysis of the five tanks was carried out for two reasons: 1) a
comparative analysis of spatial differences between distributions
showed that all records with tanks \$\Delta\$s \$\leq\$20
\emph{km} were not well explained; and 2) the spatial constraint,
reported in the literature, establishing the maximum range of
particles emitted by thunderclouds in \$\sim\$500 \emph{m}.
Detailed analysis of five tanks showed that the detection rate of
particlesjphotons per group was 7.8x \$10^{-5}\$. The duration
of the records varied between 0.27\$\mu\$s and 0.50\$\mu\$s
and their energy varied between 489.4 \emph{MeV} and 2493.2
\emph{MeV}. The \$\Delta\$t between the records and the
associated Flashes ranged from -31\$\pm\$26 \$\mu\$s and
11\$\pm\$26 \$\mu\$s, and in one of the cases it was
possible to establish that the Group happened before the recording
of the tank trace.",
committee = "Echer, Ezequiel (presidente) and Tavares, Fernanda de S{\~a}o
Sabbas (orientadora) and Gobbi, Delano and Dallaqua, Renato
S{\'e}rgio and Martin, Inacio Malmonge",
englishtitle = "Study of high energy emissions produced by electrical fields of
lightning and thunderstorms",
language = "pt",
pages = "116",
ibi = "8JMKD3MGP5W34M/3GBBC7E",
url = "http://urlib.net/ibi/8JMKD3MGP5W34M/3GBBC7E",
targetfile = "publicacao.pdf",
urlaccessdate = "04 jun. 2024"
}