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J/ApJ/706/810    X-ray emitters in the Groth-Westphal strip      (Povic+, 2009)

OTELO survey: deep BVRI broadband photometry of the Groth strip. II. Optical properties of X-ray emitters. Povic M., Sanchez-Portal M., Perez Garcia A.M., Bongiovanni A., Cepa J., Alfaro E., Castaneda H., Lorenzo M.F., Gallego J., Gonzalez-Serrano J.I., Gonzalez J.J., Lara-Lopez M.A. <Astrophys. J., 706, 810-823 (2009)> =2009ApJ...706..810P
ADC_Keywords: Galaxy catalogs ; X-ray sources ; Morphology ; Surveys ; Cross identifications Keywords: galaxies: active - X-rays: galaxies Abstract: The Groth field is one of the sky regions that will be targeted by the OSIRIS Tunable Filter Emission Line Object survey in the optical 820nm and 920nm atmospheric windows. In the present paper, public Chandra X-ray data with total exposure time of 200ks are analyzed and combined with optical broadband data of the Groth field, in order to study a set of optical structural parameters of the X-ray emitters and its relation with X-ray properties. To this aim, we processed the raw, public X-ray data using the Chandra Interactive Analysis of Observations, and determined and analyzed different structural parameters, in order to produce a morphological classification of X-ray sources. We present the morphology of 340 X-ray emitters with optical counterpart detected. Objects have been classified by X-ray type using a diagnostic diagram relating X-ray-to-optical ratio (X/O) to hardness ratio. We did not find any clear correlation between X-ray and morphological types. We analyzed the angular clustering of X-ray sources with optical counterpart using two-point correlation functions. A significant positive angular clustering was obtained from a preliminary analysis of four subsamples of the X-ray sources catalog. The clustering signal of the optically extended counterparts is similar to that of strongly clustered populations like red and very red galaxies, suggesting that the environment plays an important role in active galactic nuclei phenomena. Finally, we combined optical structural parameters with other X-ray and optical properties, and we confirmed an anticorrelation between the X/O ratio and the Abraham concentration index, which might suggest that early-type galaxies have lower Eddington rates than those of late-type galaxies. Description: Three contiguous fields centered at the original HST Groth-Westphal strip (GWS) have been observed by the AEGIS collaboration, using the Chandra/ACIS-I instrument. All data sets have been gathered from the Chandra Data Archive (ObsID from 2002 to 2005). The total field size of ACIS-I is 16.9'x16.9'. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 110 340 X-ray emitters with optical counterparts in the Groth-Westphal strip (GWS) field
See also: B/chandra : The Chandra Archive Log (CXC, 1999-) J/ApJS/180/102 : AEGIS-X: Chandra deep survey (Laird+, 2009) J/ApJS/157/175 : DEEP Groth Strip Survey. VIII. (Koo+, 2005) J/ApJ/599/1006 : DEEP Groth Strip Survey. VII. (Kobulnicky+, 2003) J/ApJ/571/136 : DEEP Groth Strip survey. X. (Im+, 2002) J/ApJS/107/1 : Morphologies of distant galaxies II (Abraham+ 1996) http://asc.harvard.edu/cda/ : Chandra Data Archive home page Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 3 I3 --- [PSP2009] [1/340] Identifier number 5- 15 F11.7 deg RAdeg Right ascension in decimal degrees (J2000) 17- 26 F10.7 deg DEdeg Declination in decimal degrees (J2000) 28- 45 E18.12 mW/m2 Fx ? Flux in full (0.5-7keV) band (in erg/cm2/s) 47- 60 F14.11 --- X/O ? X-ray to optical flux ratio (1) 62- 75 F14.11 --- HR1 ? The ((2-4.5)/(0.5-2keV)) hardness ratio 77- 82 F6.3 --- C Abraham concentration index (2) 84- 93 F10.7 --- A ? Abraham asymmetry index (Abraham et al. 1994ApJ...432...75A, 1996, Cat. J/ApJS/107/1) 95-101 A7 --- Morph Morphological type (3) 103-110 A8 --- [LNG2009] Identifier in Laird et al. AEGIS-X 2009 catalog (J/ApJS/180/102)
Note (1): X/O: X-ray-to-optical flux ratio, computed as the ratio of the observed X-ray flux in the 0.5-4.5keV energy. Note (2): C: Abraham concentration index, defined as the ratio between the integrated flux within certain radius defined by the normalized radius α=0.3, and the total flux. Note (3): Morphological type as follows: I = E/S0 galaxies (0.45≤C<0.7) II = early-type spiral galaxies: S0/S0a-Sa (0.3≤C<0.45) III = spiral galaxies: Sab-Scd (0.15≤C<0.3) IV = Irregular galaxies: Sdm-Irr (C<0.15) NI = not identified PM = possible mergers compact = compact object (QSOs, faint host AGNs, or active stars) See section 3.2 for further details.
History: From electronic version of the journal References: Cepa et al. Paper I. 2008A&A...490....1C
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 14-Dec-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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