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

## TL;DR

This paper calibrates the 1.4GHz radio continuum as a star formation rate indicator using GAMA and FIRST data, establishing a new SFR-M* relation and predicting ASKAP survey detections.

## Contribution

It provides the first robust calibration of 1.4GHz SFR relation over a wide stellar mass range and predicts future survey detections based on this calibration.

## Key findings

- New 1.4GHz luminosity-to-SFR relation with well-constrained parameters.
- First SFR-M* relation derived from radio data over two decades in stellar mass.
- Predictions for ASKAP survey detections of star-forming galaxies.

## 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.