Nick Seymour et al. 2007 ApJS 171 353 doi:10.1086/517887
The Massive Hosts of Radio Galaxies across Cosmic Time
FREE ISSUENick Seymour1, Daniel Stern2, Carlos De Breuck3, Joel Vernet3, Alessandro Rettura4, Mark Dickinson5, Arjun Dey6, Peter Eisenhardt2, Robert Fosbury3, Mark Lacy1, Pat McCarthy6, George Miley7, Brigitte Rocca-Volmerange8, Huub Röttgering9, S. Adam Stanford10,11, Harry Teplitz1, Wil van Breugel10,11 and Andrew Zirm4
Show affiliationsWe present the results of a comprehensive Spitzer survey of 69 radio galaxies across 1 < z < 5.2. Using IRAC (3.6-8.0 μm), IRS (16 μm), and MIPS (24-160 μm) imaging, we decompose the rest-frame optical to infrared spectral energy distributions into stellar, AGN, and dust components and determine the contribution of host galaxy stellar emission at rest-frame H band. Stellar masses derived from rest-frame near-IR data, where AGN and young star contributions are minimized, are significantly more reliable than those derived from rest-frame optical and UV data. We find that the fraction of emitted light at rest-frame H band from stars is >60% for ~75% of the high-redshift radio galaxies. As expected from unified models of AGNs, the stellar fraction of the rest-frame H-band luminosity has no correlation with redshift, radio luminosity, or rest-frame mid-IR (5 μm) luminosity. In addition, while the stellar H-band luminosity does not vary with stellar fraction, the total H-band luminosity anticorrelates with the stellar fraction as would be expected if the underlying hosts of these radio galaxies comprise a homogeneous population. The resultant stellar luminosities imply stellar masses of 1011-1011.5 M
even at the highest redshifts. Powerful radio galaxies tend to lie in a similar region of mid-IR color-color space as unobscured AGNs, despite the stellar contribution to their mid-IR SEDs at shorter wavelengths. The mid-IR luminosities alone classify most HzRGs as LIRGs or ULIRGs with even higher total-IR luminosities. As expected, these exceptionally high mid-IR luminosities are consistent with an obscured, highly accreting AGN. We find a weak correlation of stellar mass with radio luminosity.
- Subject headings
galaxies: active; galaxies: evolution; galaxies: high-redshift
- Dates
-
Issue 2 (2007 August)
Received 2007 January 2, accepted for publication 2007 March 2
-
The Massive Hosts of Radio Galaxies across Cosmic Time
Nick Seymour et al. 2007 ApJS 171 353
-
Non-analyticity of self-consistent field approaches: failure of predicting symmetry
L S Cederbaum et al 1990 J. Phys. B: At. Mol. Opt. Phys. 23 L747
-
Super-energy tensors
José M M Senovilla 2000 Class. Quantum Grav. 17 2799
-
Dimension theory of graphs and networks
Thomas Nowotny and Manfred Requardt 1998 J. Phys. A: Math. Gen. 31 2447
-
Non-linear Fokker–Planck integral propagator for plasma kinetic coefficients
J M Donoso et al 2005 J. Phys. A: Math. Gen. 38 9145
-
Keck Absorption-Line Spectroscopy of Galactic Winds in Ultraluminous Infrared Galaxies
David S. Rupke et al. 2002 ApJ 570 588
-
Diffraction enhanced imaging of controlled defects within bone, including bone–metal gaps
D M Connor et al 2006 Phys. Med. Biol. 51 3283
-
Multi-nuclear MRS and 19F MRI of 19F-labelled and 10B-enriched p-boronophenylalanine-fructose complex to optimize boron neutron capture therapy: phantom studies at high magnetic fields
Paola Porcari et al 2006 Phys. Med. Biol. 51 3141
-
Keck HIRES Spectroscopy of Extragalactic H II Regions: C and O Abundances from Recombination Lines
César Esteban et al. 2009 ApJ 700 654
-
The time behaviour of logarithmic amplifier input circuits
T P Flanagan 1957 J. Sci. Instrum. 34 450
Users also read
What's this?- Mid-Infrared Spectra of High-Redshift (z > 2) Radio Galaxies
- AGN Dusty Tori. II. Observational Implications of Clumpiness
- Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars