J/ApJ/742/61 Photometric redshift of AGNs from XMM- and C-COSMOS (Salvato+ 2011)
Dissecting photometric redshift for active galactic nucleus using XMM- and
Chandra-COSMOS samples.
Salvato M., Ilbert O., Hasinger G., Rau A., Civano F., Zamorani G.,
Brusa M., Elvis M., Vignali C., Aussel H., Comastri A., Fiore F.,
Le Floc'h E., Mainieri V., Bardelli S., Bolzonella M., Bongiorno A.,
Capak P., Caputi K., Cappelluti N., Carollo C.M., Contini T., Garilli B.,
Iovino A., Fotopoulou S., Fruscione A., Gilli R., Halliday C., Kneib J.-P.,
Kakazu Y., Kartaltepe J.S., Koekemoer A.M., Kovac K., Ideue Y., Ikeda H.,
Impey C.D., Le Fevre O., Lamareille F., Lanzuisi G., Le Borgne J.-F.,
Le Brun V., Lilly S., Maier C., Manohar S., Masters D., McCracken H.,
Messias H., Mignoli M., Mobasher B., Nagao T., Pello R., Puccetti S.,
Perez-Montero E., Renzini A., Sargent M., Sanders D.B., Scodeggio M.,
Scoville N., Shopbell P., Silverman J., Taniguchi Y., Tasca L., Tresse L.,
Trump J.R., Zucca E.
<Astrophys. J., 742, 61 (2011)>
=2011ApJ...742...61S 2011ApJ...742...61S
ADC_Keywords: Active gal. nuclei ; Surveys ; X-ray sources ; Redshifts
Keywords: galaxies: active - galaxies: distances and redshifts - surveys -
methods: data analysis - techniques: photometric - X-rays: galaxies
Abstract:
In this paper, we release accurate photometric redshifts for 1692
counterparts to Chandra sources in the central square degree of the
Cosmic Evolution Survey (COSMOS) field. The availability of a large
training set of spectroscopic redshifts that extends to faint
magnitudes enabled photometric redshifts comparable to the highest
quality results presently available for normal galaxies. We
demonstrate that morphologically extended, faint X-ray sources without
optical variability are more accurately described by a library of
normal galaxies (corrected for emission lines) than by active galactic
nucleus (AGN) dominated templates, even if these sources have AGN-like
X-ray luminosities. Preselecting the library on the bases of the
source properties allowed us to reach an accuracy
σΔz/(1+zspec)∼0.015 with a fraction of outliers of
5.8% for the entire Chandra-COSMOS sample. In addition, we release
revised photometric redshifts for the 1735 optical counterparts of the
XMM-detected sources over the entire 2deg2 of COSMOS. For 248
sources, our updated photometric redshift differs from the previous
release by Δz>0.2. These changes are predominantly due to the
inclusion of newly available deep H-band photometry (HAB=24mag).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 56 1694 Extracted from C-COSMOS photometric redshift catalog
table5.dat 56 1735 Extracted from XMM-COSMOS photometric redshift catalog
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See also:
II/284 : COSMOS Multi-Wavelength Photometry Catalog (Capak+, 2007)
J/ApJS/201/30 : The Chandra COSMOS survey. III. (Civano+, 2012)
J/A+A/542/A16 : X-ray detection of radio-selected SF galaxies (Ranalli+, 2012)
J/ApJ/716/348 : The XMM-Newton survey of the COSMOS field (Brusa+, 2010)
J/A+A/512/A34 : XMM-COSMOS Type 1 AGNs (Lusso+, 2010)
J/ApJ/693/8 : High-redshift QSOs in the COSMOS survey (Brusa+, 2009)
J/ApJ/696/1195 : COSMOS AGN spectroscopic survey. I. (Trump+, 2009)
J/A+A/497/635 : XMM-Newton survey in COSMOS field (Cappelluti+, 2009)
J/ApJ/680/939 : Optical spectra of 24um galaxies in COSMOS. I. (Caputi+, 2008)
J/ApJS/172/523 : COSMOS field Lyα emitters at z∼5.7 (Murayama+, 2007)
J/ApJS/172/383 : AGN candidates in the COSMOS field (Trump+, 2007)
J/ApJS/172/368 : XMM-Newton survey in COSMOS field. IV. (Mainieri+, 2007)
J/ApJS/172/70 : zCOSMOS-bright catalog (Lilly+, 2007)
J/ApJS/172/29 : XMM-Newton survey in COSMOS field. I. (Hasinger+, 2007)
http://cosmos.astro.caltech.edu/ : COSMOS home page
http://irsa.ipac.caltech.edu/data/COSMOS/ : COSMOS archive
http://www.mpe.mpg.de/~mara/PHOTOZ_XCOSMOS/ : XMM- C-COSMOS photometric z cat.
Byte-by-byte Description of file: table[45].dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- XID [1/100382] X-ray identifier (1)
8- 14 I7 --- OID ?=-99 Optical counterpart identifier (2)
16- 20 F5.3 --- zph [0/7] Photometric redshift (0=star)
22- 26 F5.3 --- b_zph Lower value on zph
27 A1 --- n_zph [*] Lower value forced (5)
28- 32 F5.3 --- B_zph Upper value on zph
33 A1 --- f_zph [*] Upper value forced (5)
34- 40 F7.3 --- PDFz [14.06/100.1]?=-99 Redshift probability distribution
42- 44 I3 --- Temp [1/131]?=-99 Best-fit template (3)
47- 49 I3 --- Cl [1/4]?=-99 Morphological classification (4)
51- 56 F6.2 mag VAR [0/2.1]?=-99 Variability parameter defined as Eq.(1)
in Salvato et al. 2009ApJ...690.1250S 2009ApJ...690.1250S
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Note (1): Chandra identifier from Civano et al. 2012, Cat. J/ApJS/201/30,
(Col. CID; in Simbad) for table 4.
XMM identifier from Brusa et al. 2010, Cat. J/ApJ/716/348,
in Simbad for table 5.
Note (2): As reported in the photo-z catalog (Ilbert et al. 2009ApJ...690.1236I 2009ApJ...690.1236I;
Column 2) and in the photometric catalog "cosmosphot20081101"
available in the COSMOS web page:
http://irsa.ipac.caltech.edu/data/COSMOS/tables/photometry/
Note (3): Best-fit template: from 1 to 31 the templates are from Salvato et al.
2009ApJ...690.1250S 2009ApJ...690.1250S, templates from 100+(1...30) are from the
Ilbert et al. 2009ApJ...690.1236I 2009ApJ...690.1236I library.
Note (4): From Leauthaud et al. 2007ApJS..172..219L 2007ApJS..172..219L. 1 or 3 indicates extended
sources, while 2 or 4 indicates point-like sources.
Note (5): The asterisk, in table5 only, was added at CDS when the limit
value was changed; see the "History" section below.
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History:
* 24-Oct-2012: From electronic version of the journal
* 13-Dec-2012: In table5, 3 lower values of zph, higher than the actual
zph, were forced to zph value (records#153, 872 and 907).
Similarly, 5 upper values of zph, lower than the actual zph,
were forced to zph value (records# 66, 435, 456, 733, 955)
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 24-Oct-2012