The SAMI Galaxy Survey: the discovery of a luminous, low-metallicity H II complex in the dwarf galaxy GAMA J141103.98-003242.3 ...

• Main Authors: Richards, S. N., Bloom, J. V., Brough, S., Fogarty, L. M. R., Goodwin, M., Green, A. W., Ho, I. - T., Kewley, L. J., Koribalski, B. S., Lawrence, J. S., Owers, M. S., Schaefer, A. L., Sadler, E. M., Sharp, R., Lopez-Sanchez, A. R., Croom, S. M., Bryant, J. J., Sweet, Sarah, Konstantopoulos, I. S., Allen, J. T., Bland-Hawthorn, J.
• Format: Text
• Language: unknown
• Published: Swinburne 2024
• Subjects: Cosmology and extragalactic astronomy; sami
• Online Access: https://dx.doi.org/10.25916/sut.26243039; https://swinburne.figshare.com/articles/journal_contribution/The_SAMI_Galaxy_Survey_the_discovery_of_a_luminous_low-metallicity_H_II_complex_in_the_dwarf_galaxy_GAMA_J141103_98-003242_3/26243039

We present the discovery of a luminous unresolved H ii complex on the edge of dwarf galaxy GAMA J141103.98−003242.3 using data from the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. This dwarf galaxy is situated at a distance of ∼100 Mpc and contains an unresolved region of H ii emission that contributes ∼70 per cent of the galaxy's Hα luminosity, located at the top end of established H ii region luminosity functions. For the H ii complex, we measure a star formation rate of 0.147 ± 0.041 M⊙ yr−1and a metallicity of 12+log(O/H) = 8.01 ± 0.05 that is lower than the rest of the galaxy by ∼0.2 dex. Data from the H i Parkes All-Sky Survey (HIPASS) indicate the likely presence of neutral hydrogen in the galaxy to potentially fuel ongoing and future star-forming events. We discuss various triggering mechanisms for the intense star formation activity of this H ii complex, where the kinematics of the ionized gas are well described by a rotating disc and do not show any features indicative ...