The Structural Evolution of Milky Way-like Star Forming Galaxies since
  z~1.3
  We follow the structural evolution of star forming galaxies (SFGs) like the
Milky Way by selecting progenitors to z~1.3 based on the stellar mass growth
inferred from the evolution of the star forming sequence. We select our sample
from the 3D-HST survey, which utilizes spectroscopy from the HST WFC3 G141
near-IR grism and enables precise redshift measurements for our sample of SFGs.
Structural properties are obtained from Sersic profile fits to CANDELS WFC3
imaging. The progenitors of z=0 SFGs with stellar mass M=10^{10.5} Msun are
typically half as massive at z~1. This late-time stellar mass assembly is
consistent with recent studies that employ abundance matching techniques. The
descendant SFGs at z~0 have grown in half-light radius by a factor of ~1.4
since z~1. The half-light radius grows with stellar mass as r_e M^{0.29}. While
most of the stellar mass is clearly assembling at large radii, the mass surface
density profiles reveal ongoing mass growth also in the central regions where
bulges and pseudobulges are common features in present day late-type galaxies.
Some portion of this growth in the central regions is due to star formation as
recent observations of H-alpha maps for SFGs at z~1 are found to be extended
but centrally peaked. Connecting our lookback study with galactic archeology,
we find the stellar mass surface density at R=8 kpc to have increased by a
factor of ~2 since z~1, in good agreement with measurements derived for the
solar neighborhood of the Milky Way.
