Journal article
Spatially resolved direct method metallicity in a high-redshift analogue local galaxy: Temperature structure impact on metallicity gradients
AJ Cameron, T Yuan, M Trenti, DC Nicholls, LJ Kewley
Monthly Notices of the Royal Astronomical Society | OXFORD UNIV PRESS | Published : 2021
Abstract
We investigate how H ii region temperature structure assumptions affect 'direct-method' spatially resolved metallicity observations using multispecies auroral lines in a galaxy from the SAMI Galaxy Survey. SAMI609396B, at redshift z = 0.018, is a low-mass galaxy in a minor merger with intense star formation, analogous to conditions at high redshifts. We use three methods to derive direct metallicities and compare with strong-line diagnostics. The spatial metallicity trends show significant differences among the three direct methods. Our first method is based on the commonly used electron temperature Te([O iii]) from the [O iii]λ4363 auroral line and a traditional Te([O ii]) - Te([O iii]) cal..
View full abstractRelated Projects (1)
Grants
Awarded by Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D)
Funding Acknowledgements
We would like to thank Rob Yates for detailed discussions about the Yates et al. (2020) semidirect method and for sharing insights on using the O32 ratio to distinguish between lower and upper branch values in Fig. D1. We are grateful to Tucker Jones for valuable discussions about this work and to Jesse van de Sande and Ned Taylor for sharing SAMI-related expertise. We would also like to thank the referee for their constructive suggestions which certainly improved this work. This study was based on publicly released data from the SAMI Galaxy Survey. The SAMI Galaxy Survey is based on observations made at the Anglo-Australian Telescope. The Sydney AAO Multi-object Integral field spectrograph (SAMI) was developed jointly by the University of Sydney and the Australian Astronomical Observatory. This research was supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. AJC acknowledges support from an Australian Government Research Training Program (RTP) Scholarship.