Energetic Sources and the Interstellar Medium: A Case Study of the Scutum Supershell

Abstract

This thesis investigates large-scale Hα spine and bow shock features associated with the Scutum Supershell using multi-wavelength observations. Through photoionisation modelling, optical spectroscopy with WiFeS, and diagnostic line ratios, we distinguish photoionised and shock-excited regions. The spine is consistent with photoionisation from OB associations, while the bow shock exhibits characteristics of low-velocity shocks. Evidence from radio, infrared, and X-ray maps supports these findings. Additionally, a circular Hough transform algorithm is developed for automated detection of shell-like structures, with applications demonstrated on radio and CO data. This work contributes to understanding high-energy feedback in the interstellar medium.