\documentclass[../main.tex]{subfiles}

\begin{document}
\chapter{Airshowers}
\label{sec:airshowers}

\section{Cosmic Rays}

\section{Detectors}

Pierre Auger,
GRAND

\subsection{Surface Detector}

\subsection{Radio Detector}

\section{Interferometry}
Requires $\sigma_t \lesssim 1\ns$

\end{document}
