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J/AJ/126/2209       X-ray AGN from RASS and SDSS             (Anderson+, 2003)

A large, uniform sample of X-Ray-Emitting AGNs: selection approach and an initial catalog from the ROSAT All-Sky and Sloan Digital Sky Surveys. Anderson S.F., Voges W., Margon B., Trumper J., Agueros M.A., Boller T., Collinge M.J., Homer L., Stinson G., Strauss M.A., Annis J., Gomez P., Hall P.B., Nichol R.C., Richards G.T., Schneider D.P., Vanden Berk D.E., Fan X., Ivezic Z., Munn J.A., Newberg H.J., Richmond M.W., Weinberg D.H., Yanny B., Bahcall N.A., Brinkmann J., Fukugita M., York D.G. <Astron. J., 126, 2209-2229 (2003)> =2003AJ....126.2209A
ADC_Keywords: X-ray sources ; QSOs ; Active gal. nuclei ; Surveys ; Photometry, SDSS Keywords: catalogs - quasars: general - surveys - X-rays Abstract: We describe the initial results of a new program aimed to ultimately yield ∼104 fully characterized X-ray source identifications - a sample about an order of magnitude larger than earlier efforts. The technique is detailed and employs X-ray data from the ROSAT All-Sky Survey (RASS, Cat. IX/10, IX/29) and optical imaging and spectroscopic follow-up from the Sloan Digital Sky Survey (SDSS, J/AJ/123/567); these two surveys prove to be serendipitously very well matched in sensitivity. As part of the SDSS software pipelines, optical objects in the SDSS photometric catalogs are automatically positionally cross-correlated with RASS X-ray sources. Then priorities for follow-on SDSS optical spectra of candidate counterparts are automatically assigned using an algorithm based on the known ratios of fX/fopt for various classes of X-ray emitters at typical RASS fluxes of 10-13ergs/cm2/s. SDSS photometric parameters for optical morphology, magnitude, and colors, plus FIRST radio information, serve as proxies for object class. Description: We present initial results toward the ultimate goal of a sample of ∼104 well-characterized optical identifications of RASS X-ray sources. The emphasis in this installment of the RASS/SDSS catalog is on our initial set of more than 1200 X-ray-emitting quasars and other sorts of AGNs. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 107 964 Observed Parameters of Broad-Line RASS/SDSS AGN table2.dat 111 964 Derived Parameters of Broad-Line RASS/SDSS AGN table3.dat 107 216 Observed Parameters of Broad-Line RASS/SDSS AGN Having Narrower Permitted Emission table4.dat 111 216 Derived Parameters of RASS/SDSS AGN Having Narrower Permitted Emission table5.dat 107 45 Observed Parameters of RASS/SDSS BL Lac Candidates table6.dat 111 45 Derived Parameters of RASS/SDSS BL Lac Candidates
See also: IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999) IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000) J/AJ/123/567 : SDSS quasar catalog, I: Early Data Release (Schneider+, 2002) J/ApJ/596/437 : Stellar-mass black holes in the SDSS (Chisholm+, 2003) Byte-by-byte Description of file: table1.dat table3.dat table5.dat
Bytes Format Units Label Explanations
1- 15 A15 --- RASS RASS X-ray source name (1) 17- 34 A18 --- SDSS SDSS optical counterpart name (1) 36- 40 F5.2 mag u*mag The SDSS u* band PSF magnitude 42- 46 F5.2 mag g*mag The SDSS g* band PSF magnitude 48- 52 F5.2 mag r*mag The SDSS r* band PSF magnitude 54- 58 F5.2 mag i*mag The SDSS i* band PSF magnitude 60- 64 F5.2 mag z*mag The SDSS z* band PSF magnitude 66 I1 --- OType Optical morphology (2) 68- 72 F5.3 --- z ? Redshift from the SDSS spectra 74- 79 F6.4 ct/s CRate RASS 0.1-2.4keV count rate 81- 84 I4 s Exp RASS exposure time 86- 90 F5.2 --- HR1 RASS hardness ratio 1 (3) 92- 96 F5.2 --- HR2 RASS hardness ratio 2 (4) 98-101 I4 --- Detect Source detection likelihood 103-107 F5.2 10-16W/m2 FX RASS absorbed 0.1-2.4keV flux in units of 10-13erg/s/cm2
Note (1): And position (J2000) using RA/DE nomenclature. Note (2): See Stoughton et al. (2002AJ....123..485S) for more details. 3 = extended/resolved (i.e., galaxy) morphology; 6 = stellar/unresolved morphology. Note (3): HR1 = (B-A)/(B+A) where A is the PHA 11-41 channel counts and B is the PHA 52-201 channel counts. Note (4): HR2 = (D-C)/(D+C) where C is the PHA 52-90 channel counts and D is the PHA 91-201 channel counts.
Byte-by-byte Description of file: table2.dat table4.dat table6.dat
Bytes Format Units Label Explanations
1- 15 A15 --- RASS RASS X-ray source name (1) 17- 34 A18 --- SDSS SDSS optical counterpart name (1) 36- 40 F5.2 mag g*0mag The SDSS g*0 band PSF magnitude (2) 42- 46 F5.3 --- z ? Redshift from the SDSS spectra 48- 53 F6.2 10-13mW/m2 FXcor RASS absorbed 0.1-2.4keV flux (3) 55- 59 F5.2 [10-7W] logLX ? Log of broadband 0.1-2.4kev X-ray luminosity in units of erg/s (4) 61- 65 F5.2 [10-7W/Hz] LogL2500 ? Log of monochromatic optical luminosity at 2500 Angstroms in units of erg/s/Hz (4) 67- 71 F5.2 [10-7W/Hz] LogL2kev ? Log of monochromatic X-ray luminosity at 2kev in units of erg/s/Hz (4) 73- 76 F4.2 --- alphaox Slope of a hypothetical power law from 2500Å to 2keV 78-111 A34 --- Com Additional comments
Note (1): And position (J2000) using RA/DE nomenclature. Note (2): Corrected for extinction according to the reddening maps of Schlegel, Finkbeiner, & Davis (1998ApJ...500..525S). Note (3): In units of 10-13erg/s/cm2 and corrected for Galactic absorption and with absorbing columns estimated from the NH column density measures of the Stark et al. (1992, Cat. VIII/10) 21cm maps. Note (4): We adopt values of H0=70km/s/Mpc, ΩM=0.3, and ΩΛ=0.7 for deriving the luminosities.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 19-Dec-2003
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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