Exploring the Correlation of Oxygen Abundance and Ionization Parameter in NGC 628 with SIGNALS

Image Credit: ESA/Webb, NASA & CSA, J. Lee and the PHANGS-JWST Team


The variations of oxygen abundance and ionization parameter in HII regions are usually thought to be the dominant factors that produce the variations seen in observed emission line spectra. However, if and how these two quantities are physically related is hotly debated in the literature. We present ongoing research into the correlation between abundance and ionization parameter using the Star formation, Ionized Gas, and Nebular Abundances Legacy Survey’s (SIGNALS) large sample of Local Universe HII regions collected with the CFHT imaging spectrograph SITELLE. Using a combination of this large observational data set and photoionization models, we show that the correlation (if any) between ionization parameter and oxygen abundance is highly model dependent.

Apr 18, 2024
Space Telescope Science Institute
3700 San Martin Dr, Baltimore, MD 21218
Ray Garner
Ray Garner
TAMU Astronomy Postdoctoral Researcher

I’m a scientist, Star Wars fan, and amateur photographer raised in Georgia. My research interests include galaxy evolution, star formation, satellite galaxies, and nebular diagnostics.