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Candels: The Progenitors of Compact Quiescent Galaxies at Z 2
Astrophysical Journal Letters (2011)
  • Guillermo Barro
  • S. M. Faber
  • Pablo G. P´erez-Gonz´alez
  • David C. Koo
  • Christina C. Williams
  • Dale D. Kocevski
  • Jonathan R. Trump
  • Mark Mozena
  • Elizabeth McGrath
  • Arjen van der Wel
  • Stijn Wuyts
  • Eric F. Bell
  • Darren J. Croton
  • Avishai Dekel
  • M. L. N. Ashby
  • Henry C. Ferguson
  • Adriano Fontana
  • Mauro Giavalisco, University of Massachusetts - Amherst
  • Norman A. Grogin
  • Yicheng Guo
  • Nimish P. Hathi
  • Philip F. Hopkins
  • Kuang-Han Huang
  • Anton M. Koekemoer
  • Jeyhan S. Kartaltepe
  • Kyoung-Soo Lee
  • Jeffrey A. Newman
  • Lauren A. Porter
  • Joel R. Primack
  • Russell E. Ryan
  • David Rosario
  • Rachel S. Somerville
We combine high-resolution HST/WFC3 images with multi-wavelength photometry to track the evolution of structure and activity of massive (log(M*) > 10) galaxies at redshifts z = 1.4 - 3 in two fields of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). We detect compact, star-forming galaxies (cSFGs) whose number densities, masses, sizes, and star formation rates qualify them as likely progenitors of compact, quiescent, massive galaxies (cQGs) at z = 1.5 - 3. At z > 2 most cSFGs have specific star-formation rates (sSFR = 10^-9 yr^-1) half that of typical, massive SFGs at the same epoch, and host X-ray luminous AGN 30 times (~30%) more frequently. These properties suggest that cSFGs are formed by gas-rich processes (mergers or disk-instabilities) that induce a compact starburst and feed an AGN, which, in turn, quench the star formation on dynamical timescales (few 10^8 yr). The cSFGs are continuously being formed at z = 2 - 3 and fade to cQGs by z = 1.5. After this epoch, cSFGs are rare, thereby truncating the formation of new cQGs. Meanwhile, down to z = 1, existing cQGs continue to enlarge to match local QGs in size, while less-gas-rich mergers and other secular mechanisms shepherd (larger) SFGs as later arrivals to the red sequence. In summary, we propose two evolutionary scenarios of QG formation: an early (z > 2), fast-formation path of rapidly-quenched cSFGs that evolve into cQGs that later enlarge within the quiescent phase, and a slow, late-arrival (z < 2) path for SFGs to form QGs without passing through a compact state.
  • galaxies: starburst,
  • galaxies: photometry,
  • galaxies: high-redshift
Publication Date
Publisher Statement
This paper was harvested from and ArXiv identifier is arXiv:1206.5000.
Citation Information
Guillermo Barro, S. M. Faber, Pablo G. P´erez-Gonz´alez, David C. Koo, et al.. "Candels: The Progenitors of Compact Quiescent Galaxies at Z 2" Astrophysical Journal Letters (2011)
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