Description:

Abstract: The 1.4 GHz radio continuum emission from star-forming galaxies (SFGs) is primarily synchrotron radiation from electrons accelerated in the supernova remnants of short-lived (τ < 30 Myr) massive stars, making it a good tracer of current star formation that is unbiased by dust absorption and uncontaminated by older stellar populations. The local radio luminosity function of SFGs yields the star-formation rate density (SFRD) in the universe today. The radio sources in cosmologically distant SFGs are very weak, but the recent MeerKAT DEEP2 image has resolved > 96% of the SFG radio background into sources as faint as 0.25 microJy. Evolving the local radio luminosity function to match the DEEP2 faint-source counts yields an independent radio estimate of the star-formation history of the universe.

Speaker: Jim Condon, National Radio Astronomy Observatory