The angular momentum of disc galaxies at z=1

We investigate the relation between stellar mass (M*) and specific stellar angular momentum (j*), or Fall relation, for a sample of 17 isolated, regularly rotating disc galaxies at z similar to 1. All galaxies have rotation curves determined from H alpha emission-line data; HST imaging in optical and infrared filters; and robust determinations of their stellar masses. We use HST images in f814w and f160w filters, roughly corresponding to rest-frames B and I bands, to extract surface-brightness profiles for our systems. We robustly bracket j* by assuming that rotation curves beyond the outermost H alpha rotation point stay either flat or follow a Keplerian fall-off. By comparing our measurements with those determined for disc galaxies in the local universe, we find no evolution in the Fall relation in the redshift range 0 < z < 1, regardless of the band used and despite the uncertainties in the stellar rotation curves at large radii. This result holds unless stellar masses at z = 1 are systematically underestimated by greater than or similar to 50%. Our findings are compatible with expectations based on a ACDM cosmological framework and support a scenario where both the stellar Tully-Fisher and mass-size relations for spirals do not evolve significantly in this redshift range.