Abstract

Origins and fate of the highest known redshift galaxy: Implications for JWST

Stuart Wyithe (University of Melbourne)

Simon Mutch, University of Melbourne Garth Illingworth, UC Santa Cruz Pascal Oesch, Observatoire de Genève

We have investigated the formation mechanisms and eventual fate of the recently identified z~11 galaxy GN-z11 using analog galaxies identified in the DRAGONS simulations. The modelling suggests that galaxies of similar luminosity to the remarkably bright GN-z1 (M_UV=-22.1) may not be as rare as extrapolations of lower redshift observed luminosity functions suggest, and that JWST will be able to detect the progenitors of GN-z11 analogues out to z~15. By modelling the size-luminosity relation we also show that JWST will be able to resolve the GN-z11 like progenitors, pushing the frontier of galaxy-formation observation to the very earliest stages of cosmic reionization. GN-z11 analogs are found to have smooth stellar mass growth histories with consistently high star formation rates and UV luminosities, indicating that their brightness is not transient. Moreover, although GN-z11 analogues are relatively rare outliers from the full galaxy population at z~11, they are no longer the most massive or brightest systems among the well studied population of galaxies at z~6.

Talk