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J/ApJ/691/705       AGN host galaxy morphologies in COSMOS        (Gabor+, 2009)

Active galactic nucleus host galaxy morphologies in COSMOS. Gabor J.M., Impey C.D., Jahnke K., Simmons B.D., Trump J.R., Koekemoer A.M., Brusa M., Cappelluti N., Schinnerer E., Smolcic V., Salvato M., Rhodes J.D., Mobasher B., Capak P., Massey R., Leauthaud A., Scoville N. <Astrophys. J., 691, 705-722 (2009)> =2009ApJ...691..705G
ADC_Keywords: Galaxies, optical ; Active gal. nuclei ; Photometry, HST ; Morphology ; Redshifts ; Surveys Keywords: galaxies: active - galaxies: evolution - galaxies: interactions - galaxies: structure Abstract: We use Hubble Space Telescope/Advanced Camera for Surveys images and a photometric catalog of the Cosmic Evolution Survey (COSMOS) field to analyze morphologies of the host galaxies of ∼400 active galactic nucleus (AGN) candidates at redshifts 0.3<z<1.0. We compare the AGN hosts with a sample of nonactive galaxies drawn from the COSMOS field to match the magnitude and redshift distribution of the AGN hosts. We perform two-dimensional surface brightness modeling with GALFIT to yield host galaxy and nuclear point source magnitudes. X-ray-selected AGN host galaxy morphologies span a substantial range that peaks between those of early-type, bulge-dominated and late-type, disk-dominated systems. We also measure the asymmetry and concentration of the host galaxies. Unaccounted for, the nuclear point source can significantly bias results of these measured structural parameters, so we subtract the best-fit point source component to obtain images of the underlying host galaxies. Our concentration measurements reinforce the findings of our two-dimensional morphology fits, placing X-ray AGN hosts between early- and late-type inactive galaxies. AGN host asymmetry distributions are consistent with those of control galaxies. Description: COSMOS (Scoville et al. 2007ApJS..172....1S), a Hubble Space Telescope Treasury project, includes coverage of a 2deg2 field from X-ray wavelengths to UV, optical, IR, and radio. The cornerstone data set, which we use for the bulk of our analysis, consists of 583 orbits taken with Hubble's Advanced Camera for Surveys (ACS) with the F814W filter (see Koekemoer et al. 2007ApJS..172..196K for a complete description). Ancillary observations include XMM-Newton X-ray imaging (Hasinger et al. 2007, Cat. J/ApJS/172/29), VLA radio maps (Schinnerer et al. 2007, Cat. J/ApJS/172/46), and VLT/VIMOS (Lilly et al. 2007, Cat. J/ApJS/172/70) and Magellan/IMACS optical spectroscopy (Trump et al. 2007, Cat. J/ApJS/172/383; 2009ApJ...700...49T; 2009ApJ...706..797T). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 134 391 Results of 2-D fits
See also: II/284 : COSMOS Multi-Wavelength Photometry Catalog (Capak+, 2007) J/ApJS/172/29 : XMM-Newton survey in COSMOS field. I. (Hasinger+, 2007) J/ApJS/172/46 : VLA-COSMOS survey. II. (Schinnerer+, 2007) J/ApJS/172/383 : AGN candidates in the COSMOS field (Trump+, 2007) J/ApJS/172/70 : zCOSMOS-bright catalog (Lilly+, 2007) J/ApJS/172/368 : XMM-Newton survey in COSMOS field. IV. (Mainieri+, 2007) J/A+A/512/A34 : XMM-COSMOS Type 1 AGNs (Lusso+, 2010) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 7 A7 --- --- [COSMOS_] 8- 26 A19 --- COSMOS Object identification (JHHMMSS.ss+DDMMSS.s) 28- 35 F8.4 deg RAdeg Right Ascension in decimal degrees (J2000) (1) 37- 42 F6.4 deg DEdeg Declination in decimal degrees (J2000) (1) 44- 47 F4.2 --- z Spectroscopic redshift (2) 49- 53 F5.2 mag mh Host galaxy apparent HST F814W magnitude (3) 55- 58 F4.2 mag e_mh Uncertainty estimate in Imagh (4) 60- 64 F5.2 mag mh* Host galaxy apparent F814W magnitude without nuclear point source component (3) 66- 71 F6.2 pix rp Host galaxy effective F814W image radius (3) 73- 78 F6.2 pix e_rp Uncertainty estimate in rp (4) 80- 85 F6.2 pix rh* Host galaxy effective F814W image radius without nuclear point source component (3) 87- 90 F4.2 --- nh Host galaxy Sersic index (3) 92- 95 F4.2 --- e_nh Uncertainty estimate in nh (4) 97-100 F4.2 --- nh* Host galaxy Sersic index without nuclear point source component (3) 102-106 F5.2 mag mp Nuclear point source HST F814W magnitude (3) 108-111 F4.2 mag e_mp Uncertainty estimate in Imagp (4) 113-116 F4.2 --- A Asymmetry morphological indicator 118-122 F5.2 --- C Concentration morphological indicator (5) 124-128 F5.1 pix rn0 Petrosian radius 130 I1 --- Flag Fit flag (0=OK) (6) 132-134 A3 --- Class Spectral class (7)
Note (1): Positions are for optical counterparts to the XMM-Newton X-ray point-source catalog (Cappelluti et al. 2007ApJS..172..341C) and the VLA radio source catalog (Schinnerer et al. 2007, Cat. J/ApJS/172/46). Note (2): Redshifts are derived from optical spectra from Magellan/IMACS and MMT/Hectospec (Trump et al. 2007, Cat. J/ApJS/172/383). Note (3): Best-fit morphological parameters based on 2-D surface brightness fits (1 pixel=0.03"). Note (4): Based on fits to our simulated AGN images, and give the 1-σ scatter on each parameter for an AGN with the given mean surface brightness. Note (5): The concentration parameter serves as an alternative to the Sersic index to determine whether a galaxy is dominated by a highly concentrated central bulge component. Here we define the concentration as C=5log(r>/r<), with r>=0.9rη0 and r<=0.5rη0. Note (6): Fit flags as follows: 0 = Successful automated fit; 1 = Fit runs into boundaries; 2 = Successful manual fit; 3 = Fit better without PSF component; 4 = Poor fit (subjective). Note (7): From Trump et al. (2007, Cat. J/ApJS/172/383). The first letter indicates X-ray ("x") or radio ("r") selected objects, and the numbers indicate optical spectral types as follows: 1 = Broad line AGN, 2 = Narrow lines, 23 = Hybrid Narrow line/Red galaxy, 3 = Red Galaxy.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 22-Feb-2011
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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