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arXiv · 2211.15998

Galaxy And Mass Assembly (GAMA): The Dependence of Star Formation on Surface Brightness in Low Redshift Galaxies

S. Phillipps·S. Bellstedt·M. N. Bremer·R. De Propris·P. A. James·S. Casura·J. Liske·B. W. Holwerda
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Abstract

The star formation rate in galaxies is well known to correlate with stellar mass (the `star-forming main sequence'). Here we extend this further to explore any additional dependence on galaxy surface brightness, a proxy for stellar mass surface density. We use a large sample of low redshift ($z \leq 0.08$) galaxies from the GAMA survey which have both SED derived star formation rates and photometric bulge-disc decompositions, the latter providing measures of disc surface brightness and disc masses. Using two samples, one of galaxies fitted by a single component with S\'{e}rsic index below 2 and one of the discs from two-component fits, we find that once the overall mass dependence of star formation rate is accounted for, there is no evidence in either sample for a further dependence on stellar surface density.

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S. Phillipps, S. Bellstedt, M. N. Bremer, R. De Propris, P. A. James, S. Casura, J. Liske, B. W. Holwerda. 2022-11-29. Galaxy And Mass Assembly (GAMA): The Dependence of Star Formation on Surface Brightness in Low Redshift Galaxies. https://doi.org/10.1093/mnras%2Fstac3440

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