VLA AND ALMA IMAGING OF INTENSE GALAXY-WIDE STAR FORMATION IN z ∼ 2 GALAXIES
Dunlop, J. S.
Rieke, George H.
Ivison, R. J.
Silverman, J. D.
Alexander, David M.
Biggs, A. D.
Ballantyne, D. R.
Geach, J. E.
Hayward, C. C.
McLure, R. J.
Michałowski, M. J.
Miller, N. A.
Owen, F. N.
Robertson, Brant E.
Swinbank, A. M.
Werf, P. van der
Kampen, E. van
Windhorst, R. A.
AffiliationUniv Arizona, Steward Observ
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationVLA AND ALMA IMAGING OF INTENSE GALAXY-WIDE STAR FORMATION IN z ∼ 2 GALAXIES 2016, 833 (1):12 The Astrophysical Journal
JournalThe Astrophysical Journal
Rights© 2016. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractWe present; 0 4 resolution extinction-independent distributions of star formation and dust in 11 star-forming galaxies (SFGs) at z. =. 1.3-3.0. These galaxies are selected from sensitive blank-field surveys of the 2 x 2' Hubble Ultra-Deep Field at gimel = 5 cm and 1.3 mm using the Karl G. Jansky Very Large Array and Atacama Large Millimeter/submillimeter Array. They have star formation rates (SFRs), stellar masses, and dust properties representative of massive main-sequence SFGs at z similar to 2. Morphological classification performed on spatially resolved stellar mass maps indicates a mixture of disk and morphologically disturbed systems; half of the sample harbor X-ray active galactic nuclei (AGNs), thereby representing a diversity of z similar to 2 SFGs undergoing vigorous mass assembly. We find that their intense star formation most frequently occurs at the location of stellar-mass concentration and extends over an area comparable to their stellar-mass distribution, with a median diameter of 4.2 similar to 1.8 kpc. This provides direct evidence of galaxy-wide star formation in distant blank-field-selected main-sequence SFGs. The typical galactic-average SFR surface density is 2.5Me circle dot yr(-1) kpc(-2), sufficiently high to drive outflows. In X-ray-selected AGN where radio emission is enhanced over the level associated with star formation, the radio excess pinpoints the AGNs, which are found to be cospatial with star formation. The median extinctionindependent size of main-sequence SFGs is two times larger than those of bright submillimeter galaxies, whose SFRs are 3-8 times larger, providing a constraint on the characteristic SFR (similar to 300Me yr(-1)) above which a significant population of more compact SFGs appears to emerge.
VersionFinal published version
SponsorsWorld Premier International Research Center Initiative (WPI), MEXT, Japan; JSPS KAKENHI [JP15K17604]; Chulalongkorn University's Ratchadapiseksompot Endowment Fund; CUniverse (CUAASC); EC FP7 SPACE project ASTRODEEP ; European Research Council [COSMICISM 321302]; ERC; YCAA Prize Postdoctoral Fellowship; NSF [AST-1442650]; NASA [HST AR-13906.001, NAS5-26555]; Cottrell College Science Award; [VLA/14A-360]
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