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arXiv · 1609.01740

Do galaxy global relationships emerge from local ones? The SDSS IV MaNGA surface mass density-metallicity relation

Jorge K. Barrera-Ballesteros·Timothy M. Heckman·Guangtun B. Zhu·Nadia L. Zakamska·Sebastian F. Sánchez·David Law·David Wake·Jenny E. Green·Dmitry Bizyaev·Daniel Oravetz·Audrey Simmons·Elena Malanushenko·Kaike Pan·Alexandre Roman Lopes·Richard R. Lane
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Abstract

We present the stellar surface mass density {\it vs.} gas metallicity ($Σ_*-Z$) relation for more than 500,000 spatially-resolved star-forming resolution elements (spaxels) from a sample of 653 disk galaxies included in the SDSS IV MaNGA survey. We find a tight relation between these local properties, with higher metallicities as the surface density increases. This relation extends over three orders of magnitude in the surface mass density and a factor of four in metallicity. We show that this local relationship can simultaneously reproduce two well-known properties of disk galaxies: their global mass-metallicity relationship {\it and} their radial metallicity gradients. We also find that the $Σ_* - Z$ relation is largely independent of the galaxy's total stellar mass and specific star-formation rate (sSFR), except at low stellar mass and high sSFR. These results suggest that in the present-day universe local properties play a key role in determining the gas-phase metallicity in typical disk galaxies.

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Jorge K. Barrera-Ballesteros, Timothy M. Heckman, Guangtun B. Zhu, Nadia L. Zakamska, Sebastian F. Sánchez, David Law, David Wake, Jenny E. Green, Dmitry Bizyaev, Daniel Oravetz, Audrey Simmons, Elena Malanushenko, Kaike Pan, Alexandre Roman Lopes, Richard R. Lane. 2016-09-06. Do galaxy global relationships emerge from local ones? The SDSS IV MaNGA surface mass density-metallicity relation. https://doi.org/10.1093/mnras%2Fstw1984

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