Bulge-forming galaxies with an extended rotating disk at z~2

Understand

We present 0".2-resolution Atacama Large Millimeter/submillimeter Array observations at 870 um for 25 Halpha-seleced star-forming galaxies (SFGs) around the main-sequence at z=2.2-2.5.

• We detect significant 870 um continuum emission in 16 (64%) of these SFGs.
• The high-resolution maps reveal that the dust emission is mostly radiated from a single region close to the galaxy center.
• Exploiting the visibility data taken over a wide $uv$ distance range, we measure the half-light radii of the rest-frame far-infrared emission for the best sample of 12 massive galaxies with logM*>11.