\documentclass[herrin-thesis.tex]{subfiles}
\begin{document}

For a particle incident from zenith angle \(\theta\) and azimuthal angle \(\phi\), the effective area of a cylinder on its side is
\begin{equation}
A(\theta,\phi) = \pi r^2 |\cos(\phi)|\sin(\theta) + 2 r h \sqrt{1-\sin(\theta)^2 \cos(\phi)^2}
\end{equation}
when \(\phi=0\) is parallel to the cylinder's axis and where \(r\) is the cylinder's radius and \(h\) is its height.

\end{document}
Add in the start of the muon chapter. Also bring in some packages.
Add in the start of the muon chapter. Also bring in some packages.
