Exploring the chemical content of Galaxies using the SAMI Zoom Survey: a data release of 92 spatially resolved H ii regions in nearby galaxies

Journal article

We present the SAMI Zoom Survey, spatially resolved IFU spectroscopy of 92 H ii regions from 7 nearby galaxies (distances 2–14 Mpc) utilizing the Sydney-AAO Multi-object IFS (SAMI) instrument. Each H ii region has two spectral data cubes (blue-arm sampling 1.05 Å pixel−1 between 3700–5746 Å, and red-arm sampling 0.57 Å pixel−1 between 6300–7399 Å) as well as two-dimensional emission line flux maps. The spatial sampling is 0.5 arcsec across 15 arcsec fields of view, with a mean angular resolution of 2.0 arcsec (18–150 pc). We investigate seven forms of common gas–phase metallicity determinations, contrasting metallicity calibrations including the direct electron temperature method and six strong-line methods. We determine these metallicities, temperatures, densities, and ionization parameters where possible, in spatially resolved form as well as an integrated-region data set where we focus our analysis. We find varying degrees of disparity between metallicity values using different methods, and likewise between derived abundance gradients of the host galaxies. In comparisons using metallicity as a baseline, mean disparities span 0.12–0.49 dex in oxygen abundance depending on the chosen alternative method, with a maximum of 0.65 dex when comparing against the direct electron temperature method. Host-galaxy abundance gradients deviate up to 0.66 dex in central oxygen abundance while slopes vary by up to 0.51 dex R−1. The SAMI Zoom Survey provides a data set with spatial resolution, spectral coverage, and radial extent to support the study of such astrophysical processes in nearby galaxies.

Authors: Myszka, A; Sweet, SM; Nanayakkara, T; Glazebrook, K; Groves, B

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Oxford University Press
• Journal: Monthly Notices of the Royal Astronomical Society
• Volume: 540
• Issue: 1
• Pages: 919-960
• Publication date: 2025-05-07
• Acceptance date: 2025-04-29
• DOI: 10.1093/mnras/staf742
• EISSN: 1365-2966
• ISSN: 0035-8711
• Language: English
• Keywords: ISM: abundances; H ii regions; galaxies: abundances; galaxies: evolution; galaxies: fundamental parameters