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The azimuthal variation of the HII region oxygen abundance in spiral galaxies is a key observable for understanding how quickly oxygen produced by massive stars can be dispersed within the surrounding interstellar medium. Observational constraints on the prevalence and magnitude of such azimuthal variations remain rare in the literature. Here, we report the discovery of pronounced azimuthal variations of HII region oxygen abundance in NGC 2997, a spiral galaxy at approximately 11.3 Mpc. Using 3D spectroscopic data from the TYPHOON Program, we study the HII region oxygen abundance at a physical resolution of 125 pc. Individual HII regions or complexes are identified in the 3D optical data and their strong emission line fluxes measured to constrain their oxygen abundances. We find 0.06 dex azimuthal variations in the oxygen abundance on top of a radial abundance gradient that is comparable to those seen in other star-forming disks. At a given radial distance, the oxygen abundances are highest in the spiral arms and lower in the inter-arm regions, similar to what has been reported in NGC 1365 using similar observations. We discuss whether the azimuthal variations could be recovered when the galaxy is observed at worse physical resolutions and lower signal-to-noise ratios.
The exploration of the spatial distribution of chemical abundances in star-forming regions in galactic discs provides clues to understand the complex interplay of physical processes that regulate the star formation activity and the chemical enrichmen
Understanding the nature of spiral structure in disk galaxies is one of the main, and still unsolved questions in galactic astronomy. However, theoretical works are proposing new testable predictions whose detection is becoming feasible with recent d
Context. The distribution of elements in galaxies forms an important diagnostic tool to characterize the systems formation and evolution. This tool is however complex to use in practice, as galaxies are subject to a range of simultaneous physical pro
We present new measurements of the interstellar gas-phase oxygen abundance along the sight lines towards 19 early-type galactic stars at an average distance of 2.6 kpc. We derive O {small I} column densities from {it HST}/STIS observations of the wea
Galactic disc chemical evolution models generally ignore azimuthal surface density variation that can introduce chemical abundance azimuthal gradients. Recent observations, however, have revealed chemical abundance changes with azimuth in the gas and