Details

Autor(en) / Beteiligte

• Barro, G.
• Kriek, M.
• Pérez-González, P. G.
• Trump, J. R.
• Koo, D. C.
• Faber, S. M.
• Dekel, A.
• Primack, J. R.
• Guo, Y.
• Kocevski, D. D.
• Muñoz-Mateos, J. C.
• Rujoparkarn, W.
• Seth, K.

Titel

SUB-KILOPARSEC ALMA IMAGING OF COMPACT STAR-FORMING GALAXIES AT z ∼ 2.5: REVEALING THE FORMATION OF DENSE GALACTIC CORES IN THE PROGENITORS OF COMPACT QUIESCENT GALAXIES

Ist Teil von

• Astrophysical journal. Letters, 2016-08, Vol.827 (2), p.L32-L32

Ort / Verlag

United States: The American Astronomical Society

Erscheinungsjahr

2016

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• ABSTRACT We present spatially resolved Atacama Large Millimeter/submillimeter Array (ALMA) 870 m dust continuum maps of six massive, compact, dusty star-forming galaxies at z ∼ 2.5. These galaxies are selected for their small rest-frame optical sizes ( kpc) and high stellar mass densities that suggest that they are direct progenitors of compact quiescent galaxies at z ∼ 2. The deep observations yield high far-infrared (FIR) luminosities of and star formation rates (SFRs) of SFR = 200-700 M yr−1, consistent with those of typical star-forming "main sequence" galaxies. The high spatial resolution (FWHM ∼ 0 12-0 18) ALMA and Hubble Space Telescope photometry are combined to construct deconvolved, mean radial profiles of their stellar mass and (UV+IR) SFR. We find that the dusty, nuclear IR-SFR overwhelmingly dominates the bolometric SFR up to r ∼ 5 kpc, by a factor of over 100× from the unobscured UV-SFR. Furthermore, the effective radius of the mean SFR profile ( kpc) is ∼30% smaller than that of the stellar mass profile. The implied structural evolution, if such nuclear starburst last for the estimated gas depletion time of Δt = 100 Myr, is a 4× increase of the stellar mass density within the central 1 kpc and a 1.6× decrease of the half-mass-radius. This structural evolution fully supports dissipation-driven, formation scenarios in which strong nuclear starbursts transform larger, star-forming progenitors into compact quiescent galaxies.