From Rings to Bulges: Evidence for Rapid Secular Galaxy Evolution at z ∼ 2 from Integral Field Spectroscopy in the SINS Survey

We present Hα integral field spectroscopy of well-resolved, UV/optically selected z ~ 2 star-forming galaxies as part of the SINS survey with SINFONI on the ESO VLT. Our laser guide star adaptive optics and good seeing data show the presence of turbulent rotating star-forming outer rings/disks, plus central bulge/inner disk components, whose mass fractions relative to the total dynamical mass appear to scale with the [N II]/Hα flux ratio and the star formation age. We propose that the buildup of the central disks and bulges of massive galaxies at z ~ 2 can be driven by the early secular evolution of gas-rich proto-disks. High-redshift disks exhibit large random motions. This turbulence may in part be stirred…

• LF
  LGS Foundation
• MF
  Max-Planck-Institut für Astronomie