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arXiv · 1701.06242

Galaxy And Mass Assembly: The 1.4GHz SFR indicator, SFR-M* relation and predictions for ASKAP-GAMA

L. J. M. Davies·M. T. Huynh·A. M. Hopkins·N. Seymour·S. P. Driver·A. G. R. Robotham·I. K. Baldry·J. Bland-Hawthorn·N. Bourne·M. N. Bremer·M. J. I. Brown·S. Brough·M. Cluver·M. W. Grootes·M. Jarvis·J. Loveday·A. Moffet·M. Owers·S. Phillipps·E. Sadler·L. Wang·S. Wilkins·A. Wright
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Abstract

We present a robust calibration of the 1.4GHz radio continuum star formation rate (SFR) using a combination of the Galaxy And Mass Assembly (GAMA) survey and the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey. We identify individually detected 1.4GHz GAMA-FIRST sources and use a late-type, non-AGN, volume-limited sample from GAMA to produce stellar mass-selected samples. The latter are then combined to produce FIRST-stacked images. This extends the robust parametrisation of the 1.4GHz-SFR relation to faint luminosities. For both the individually detected galaxies and our stacked samples, we compare 1.4GHz luminosity to SFRs derived from GAMA to determine a new 1.4GHz luminosity-to-SFR relation with well constrained slope and normalisation. For the first time, we produce the radio SFR-M* relation over 2 decades in stellar mass, and find that our new calibration is robust, and produces a SFR-M* relation which is consistent with all other GAMA SFR methods. Finally, using our new 1.4GHz luminosity-to-SFR calibration we make predictions for the number of star-forming GAMA sources which are likely to be detected in the upcoming ASKAP surveys, EMU and DINGO.

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L. J. M. Davies, M. T. Huynh, A. M. Hopkins, N. Seymour, S. P. Driver, A. G. R. Robotham, I. K. Baldry, J. Bland-Hawthorn, N. Bourne, M. N. Bremer, M. J. I. Brown, S. Brough, M. Cluver, M. W. Grootes, M. Jarvis, J. Loveday, A. Moffet, M. Owers, S. Phillipps, E. Sadler, L. Wang, S. Wilkins, A. Wright. 2017-01-23. Galaxy And Mass Assembly: The 1.4GHz SFR indicator, SFR-M* relation and predictions for ASKAP-GAMA. https://doi.org/10.1093/mnras%2Fstw3080

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