Velocity Resolved [CII] and [NII] Maps of Select HII Regions of M33
Measurements of far infrared cooling lines are ideal tools for studying the interstellar medium (ISM, Wolfire et. al. 2003). The brightest of these cooling lines is often the 158 micron line from singly-ionized carbon, or the [CII] 158 μm line (Luhman et. al. 2003), making it a frequent target of study in both local and high-z galaxies (Léfvre et. al. 2020). This emission line can originate in a wide variety of ISM environments, which complicates the utility of [CII] as an indicator of ISM properties. This complication can be overcome by using velocity-resolved maps of both the [CII] emission and the 205 μm line of singly ionized nitrogen ([NII] 205 μm). Resolved [CII] 158 μm and [NII] 205 μm maps of three HII regions in M33 obtained by the GREAT instrument onboard SOFIA are currently available on the IRS SOFIA Archive. These detailed maps are useful for a wide variety of studies of ISM conditions relating to star formation.