E. Nelson, P. van Dokkum, N. Schreiber, M. Franx, G. Brammer, I. Momcheva, S. Wuyts, K. Whitaker, R. Skelton, M. Fumagalli and 10 other author(s). (2015)cite arxiv:1507.03999Comment: Submitted to ApJ. Main results: Fig. 6 shows the scale lengths of ionized gas vs. stellar disks. Fig. 9 shows where Halpha in galaxies is enhanced above and suppressed below the star-forming main sequence. Data points for Halpha profiles are available upon request.