The z = 0.2 star formation rate density and radio luminosity function measured with the Australian Square Kilometre Array Pathfinder

We present measurements of the z = 0.2 radio continuum luminosity function of star forming galaxies derived from early observations with the Australian Square Kilometre Array Pathfinder (ASKAP). Despite 50.6 square degrees being less than 0.2% of the final ASKAP survey area, the z < 0.3 volume is sufficient to measure the star formation rate density with a precision of 9%. Our parent catalogue is the 46,314 galaxies with spectroscopic redshifts in the Galaxy and Mass Assembly (GAMA) survey G23 field. Radio continuum flux densities for each of these galaxies have been measured from ASKAP 888 MHz imaging which has an RMS of 43 micro-Jansky per beam. We find the median radio flux density of i < 19.2 star forming galaxies is comparable to the RMS of the ASKAP images, implying that most GAMA star forming galaxies will be detected by planned deeper ASKAP surveys. We find the z = 0.2 star formation rate density is 0.020 Solar masses per year per cubic Megaparsec, which is higher than some previous radio continuum measurements but comparable to recent ultraviolet and infrared measurements.