Thesis: Radio Interferometry: separate chapter

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Eric Teunis de Boone 2023-10-26 11:15:51 +02:00
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@ -10,7 +10,7 @@
\begin{document} \begin{document}
\chapter{Introduction} \chapter{Introduction}
\label{sec:introduction} \label{sec:introduction}
%<<<
% Intro Cosmic Ray % Intro Cosmic Ray
In the beginning of the $\mathrm{20^{th}}$~century, various types of radiation were discovered. In the beginning of the $\mathrm{20^{th}}$~century, various types of radiation were discovered.
With the balloonflight of Victor Hess \Todo{ref} in \Todo{year}, one type was determined to come from beyond the atmosphere and named ``Cosmic Rays''. With the balloonflight of Victor Hess \Todo{ref} in \Todo{year}, one type was determined to come from beyond the atmosphere and named ``Cosmic Rays''.
@ -29,16 +29,16 @@ However, advanced analyses require an even higher accuracy.
\\ \\
In this thesis, methods (and their limits) to obtain this accuracy for radio arrays are investigated. In this thesis, methods (and their limits) to obtain this accuracy for radio arrays are investigated.
% >>>
\section{Cosmic Particles}%<<<<<< \section{Cosmic Particles}%<<<<<<
%<<< %<<<
\label{sec:crs} \label{sec:crs}
Particles from outer space, %Particles from outer space,
Particle type, %Particle type,
Energy, %Energy,
magnetic fields -- origin, %magnetic fields -- origin,
%
\hrule %\hrule
% Cosmic Particles = CR + Photon + Neutrino % Cosmic Particles = CR + Photon + Neutrino
There is a variety of extra terrestrial particles with which the Earth is bombarded.\Todo{rephrase} There is a variety of extra terrestrial particles with which the Earth is bombarded.\Todo{rephrase}
@ -69,7 +69,7 @@ Note that cosmic rays are deemed\Todo{rephrase} to be charged nuclei.
% Energy % Energy
Cosmic rays span a large range of energy as illustrated in Figure~\ref{fig:cr_flux}. Cosmic rays span a large range of energy and flux as illustrated in Figure~\ref{fig:cr_flux}.
The acceleration of cosmic rays is thought to occur in highly energetic regions\Todo{expand} The acceleration of cosmic rays is thought to occur in highly energetic regions\Todo{expand}
\\ \\
@ -88,11 +88,11 @@ Likewise, with an rapidly increasing flux for lower energies, one component can
%>>> %>>>
\subsection{Air Showers}%<<< \subsection{Air Showers}%<<<
\label{sec:airshowers} \label{sec:airshowers}
Particle cascades, %Particle cascades,
Xmax?, %Xmax?,
Radio emission, %Radio emission,
%
\hrule %\hrule
When a particle with an energy above $1\;\TeV$ comes into contact with the atmosphere, secondary particles are generated, forming an air shower. When a particle with an energy above $1\;\TeV$ comes into contact with the atmosphere, secondary particles are generated, forming an air shower.
This air shower consists of a cascade of interactions producing more particles that subsequently undergo further interactions. This air shower consists of a cascade of interactions producing more particles that subsequently undergo further interactions.
Thus, the number of particles rapidly increases further down the air shower. Thus, the number of particles rapidly increases further down the air shower.
@ -200,103 +200,9 @@ This will be used later on and gives an insight into the timing accuracy require
\\ \\
Chapter~\ref{sec:waveform} reviews typical techniques to analyse waveforms to obtain timing information. Chapter~\ref{sec:waveform} reviews typical techniques to analyse waveforms to obtain timing information.
\\ \\
Chapter~\ref{sec:disciplining} introduces the concept of a beacon transmitter to synchronise an array of radio antennas using techniques from the preceding chapter to constrain the achievable timing accuracy. Chapter~\ref{sec:disciplining} introduces the concept of a beacon transmitter to synchronise an array of radio antennas and constrains the achievable timing accuracy using the techniques described in the preceding chapter.
\\ \\
Chapter~\ref{sec:single_sine_sync} shows\Todo{word} how a sine wave beacon can synchronise an array while using the radio interferometric approach to resolve\Todo{word} an airshower. Chapter~\ref{sec:single_sine_sync} shows\Todo{word} how a sine wave beacon can synchronise an array while using the radio interferometric approach to resolve\Todo{word} an airshower.
\\ \\
Finally, Chapter~\ref{sec:gnss_accuracy} investigates the limitations of the current hardware in \gls{GRAND} and its ability to record and reconstruct a beacon signal. Finally, Chapter~\ref{sec:gnss_accuracy} investigates the limitations of the current hardware of \gls{GRAND} and its ability to record and reconstruct a beacon signal.
\cleardoublepage
\chapter{Air Shower Radio Interferometry}
\label{sec:interferometry}
The radio signals emitted by the air shower (see Section~\ref{sec:airshowers}) can be recorded by radio antennas.
An array of radio antennas can be used as an interferometer.
Therefore, air showers can be analysed using radio interferometry.
\\
%
Unlike, astronomical interferometry, the source of the signal is closeby.
\begin{figure}
\centering
\includegraphics[width=0.5\textwidth]{radio_interferometry/rit_schematic_true.pdf}%
% \includegraphics[width=0.5\textwidth]{radio_interferometry/Schematic_RIT_extracted.png}
% \caption{From H. Schoorlemmer}
\end{figure}
\begin{equation}\label{eq:propagation_delay}%<<<
\Delta_i(\vec{x}) = \frac{ \left|{ \vec{x} - \vec{a_i} }\right| }{c} n_{eff}
\end{equation}%>>>
\begin{equation}\label{eq:interferometric_sum}%<<<
S(\vec{x}, t) = \sum_i S_i(t + \Delta_i(\vec{x}))
\end{equation}%>>>
\begin{figure}
\centering
\begin{subfigure}[t]{0.3\textwidth}
\includegraphics[width=\textwidth]{radio_interferometry/trace_overlap_bad.png}
\label{fig:trace_overlap:bad}
\end{subfigure}
\hfill
\begin{subfigure}[t]{0.3\textwidth}
\includegraphics[width=\textwidth]{radio_interferometry/trace_overlap_medium.png}
\label{fig:trace_overlap:medium}
\end{subfigure}
\hfill
\begin{subfigure}[t]{0.3\textwidth}
\includegraphics[width=\textwidth]{radio_interferometry/trace_overlap_best.png}
\label{fig:trace_overlap:best}
\end{subfigure}
\caption{
Trace overlap due to wrong positions
}
\label{fig:trace_overlap}
\end{figure}
\begin{figure}
\centering
\includegraphics[width=0.7\textwidth]{2006.10348/fig03_b.png}%
\caption{
From \protect \cite{Schoorlemmer:2020low}.
$\Xmax$ resolution as a function of detector-to-detector synchronisation.
}
\label{fig:xmax_synchronise}
\end{figure}
\section{Time Synchronisation}
\label{sec:timesynchro}
The main method of synchronising multiple stations is by employing a \gls{GNSS}.
This system should deliver timing with an accuracy in the order of $10\ns$ \cite{} (see Section~\ref{sec:grand:gnss}).
\\
Need reference system with better accuracy to constrain current mechanism (Figure~\ref{fig:reference-clock}).
%\begin{figure}
% \centering
% \includegraphics[width=0.5\textwidth]{clocks/reference-clock.pdf}
% \caption{
% Using a reference clock to compare two other clocks.
% \protect \todo{
% redo figure with less margins,
% remove spines,
% rotate labels
% }
% }
% \label{fig:reference-clock}
%\end{figure}
\end{document} \end{document}

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@ -0,0 +1,94 @@
% vim: fdm=marker fmr=<<<,>>>
\documentclass[../thesis.tex]{subfiles}
\graphicspath{
{.}
{../../figures/}
{../../../figures/}
}
\begin{document}
\chapter{Air Shower Radio Interferometry}
\label{sec:interferometry}
The radio signals emitted by the air shower (see Section~\ref{sec:airshowers}) can be recorded by radio antennas.
An array of radio antennas can be used as an interferometer.
Therefore, air showers can be analysed using radio interferometry.
\\
%
Unlike, astronomical interferometry, the source of the signal is closeby.
\begin{figure}
\centering
\includegraphics[width=0.5\textwidth]{radio_interferometry/rit_schematic_true.pdf}%
% \includegraphics[width=0.5\textwidth]{radio_interferometry/Schematic_RIT_extracted.png}
% \caption{From H. Schoorlemmer}
\end{figure}
\begin{equation}\label{eq:propagation_delay}%<<<
\Delta_i(\vec{x}) = \frac{ \left|{ \vec{x} - \vec{a_i} }\right| }{c} n_{eff}
\end{equation}%>>>
\begin{equation}\label{eq:interferometric_sum}%<<<
S(\vec{x}, t) = \sum_i S_i(t + \Delta_i(\vec{x}))
\end{equation}%>>>
\begin{figure}
\centering
\begin{subfigure}[t]{0.3\textwidth}
\includegraphics[width=\textwidth]{radio_interferometry/trace_overlap_bad.png}
\label{fig:trace_overlap:bad}
\end{subfigure}
\hfill
\begin{subfigure}[t]{0.3\textwidth}
\includegraphics[width=\textwidth]{radio_interferometry/trace_overlap_medium.png}
\label{fig:trace_overlap:medium}
\end{subfigure}
\hfill
\begin{subfigure}[t]{0.3\textwidth}
\includegraphics[width=\textwidth]{radio_interferometry/trace_overlap_best.png}
\label{fig:trace_overlap:best}
\end{subfigure}
\caption{
Trace overlap due to wrong positions
}
\label{fig:trace_overlap}
\end{figure}
\begin{figure}
\centering
\includegraphics[width=0.7\textwidth]{2006.10348/fig03_b.png}%
\caption{
From \protect \cite{Schoorlemmer:2020low}.
$\Xmax$ resolution as a function of detector-to-detector synchronisation.
}
\label{fig:xmax_synchronise}
\end{figure}
\section{Time Synchronisation}
\label{sec:timesynchro}
The main method of synchronising multiple stations is by employing a \gls{GNSS}.
This system should deliver timing with an accuracy in the order of $10\ns$ \cite{} (see Section~\ref{sec:grand:gnss}).
\\
Need reference system with better accuracy to constrain current mechanism (Figure~\ref{fig:reference-clock}).
%\begin{figure}
% \centering
% \includegraphics[width=0.5\textwidth]{clocks/reference-clock.pdf}
% \caption{
% Using a reference clock to compare two other clocks.
% \protect \todo{
% redo figure with less margins,
% remove spines,
% rotate labels
% }
% }
% \label{fig:reference-clock}
%\end{figure}
\end{document}

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@ -53,6 +53,9 @@
%% Introduction %% Introduction
\subfile{chapters/introduction.tex} \subfile{chapters/introduction.tex}
%% Radio Interferometry
\subfile{chapters/radio_interferometry.tex}
%% Electric field from airshower to waveform analysis %% Electric field from airshower to waveform analysis
\subfile{chapters/radio_measurement.tex} \subfile{chapters/radio_measurement.tex}