Dasyra, Kalliopi M. and Yan, Lin and Helou, George and Surace, Jason and Sajina, Anna and Colbert, James (2008) HST NICMOS imaging of z ~ 2, 24 µm-selected ultraluminous infrared galaxies. Astrophysical Journal, 680 (1). pp. 232-245. ISSN 0004-637X http://resolver.caltech.edu/CaltechAUTHORS:DASapj08
- Published Version
Restricted to Repository administrators only
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:DASapj08
We present Hubble Space Telescope NICMOSH-band imaging of 33 ultraluminous infrared galaxies (ULIRGs) at z ~ 2 that were selected from the 24 µm catalog of the Spitzer Extragalactic First Look Survey. The images reveal that at least 17 of the 33 objects are associated with interactions. Up to one-fifth of the sources in our sample could be minor mergers, whereas only two systems are merging binaries with luminosity ratio ≤ 3 : 1, which is characteristic of local ULIRGs. The rest-frame optical luminosities of the sources are of the order 10^(10)-10^(11) L⊙ and their effective radii range from 1.4 to 4.9 kpc. The most compact sources are either those with a strong active nucleus continuum or those with a heavy obscuration in the mid-infrared regime, as determined from Spitzer Infrared Spectrograph data. The luminosity of the 7.7 µm feature produced by polycyclic aromatic hydrocarbon molecules varies significantly among compact systems, whereas it is typically large for extended systems. A bulge-to-disk decomposition performed for the six brightest (m_H < 20) sources in our sample indicates that they are best fit by disklike profiles with small or negligible bulges, unlike the bulge-dominated remnants of local ULIRGs. Our results provide evidence that the interactions associated with ultraluminous infrared activity at z ~ 2 can differ from those at z ~ 0.
|Additional Information:||© 2008 The American Astronomical Society. Received 2007 July 19; accepted 2008 February 6. K. D. wishes to thank Lee Armus and Lisa Storrie-Lombardi for useful discussions. This work is based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute (STScI). STScI is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. It is also based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL, Caltech.|
|Subject Keywords:||galaxies: evolution; galaxies: formation; galaxies: high-redshift; galaxies: interactions; infrared: galaxies|
|Official Citation:||HST NICMOS Imaging of z ~ 2, 24 μm-selected Ultraluminous Infrared Galaxies Kalliopi M. Dasyra, Lin Yan, George Helou, Jason Surace, Anna Sajina, and James Colbert 2008 ApJ 680 232-245 doi: 10.1086/587447|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Tony Diaz|
|Deposited On:||27 Aug 2009 00:07|
|Last Modified:||26 Dec 2012 10:53|
Repository Staff Only: item control page