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J/ApJ/690/644         Properties of SDSS QSOs in the ChaMP        (Green+, 2009)

A full year's Chandra exposure on Sloan Digital Sky Survey quasars from the Chandra multiwavelength project. Green P.J., Aldcroft T.L., Richards G.T., Barkhouse W.A., Constantin A., Haggard D., Karovska M., Kim D.-W., Kim M., Vikhlinin A., Anderson S.F., Mossman A., Kashyap V., Myers A.C., Silverman J.D., Wilkes B.J., Tananbaum H. <Astrophys. J., 690, 644-669 (2009)> =2009ApJ...690..644G
ADC_Keywords: Photometry, SDSS ; QSOs ; X-ray sources ; Surveys ; Redshifts Keywords: galaxies: active - quasars: absorption lines - quasars: general - surveys - X-rays: general Abstract: We study the spectral energy distributions and evolution of a large sample of optically selected quasars from the Sloan Digital Sky Survey that were observed in 323 Chandra images analyzed by the Chandra Multiwavelength Project. Our highest-confidence matched sample includes 1135 X-ray detected quasars in the redshift range 0.2<z<5.4, representing some 36Msec of effective exposure. We provide catalogs of QSO properties, and describe our novel method of calculating X-ray flux upper limits and effective sky coverage. Spectroscopic redshifts are available for about 1/3 of the detected sample; elsewhere, redshifts are estimated photometrically. We detect 56 QSOs with redshift z>3, substantially expanding the known sample. We find no evidence for evolution out to z∼5 for either the X-ray photon index Γ or for the ratio of optical/UV to X-ray flux αox. Description: The ChaMP (Kim et al., 2007, Cat. J/ApJS/169/401) is a wide-area serendipitous X-ray survey based on archival X-ray images of the (|b|<20deg) sky observed with the AXAF CCD Imaging Spectrometer (ACIS) onboard Chandra. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 272 1135 Properties of SDSS quasars detected by Chandra table3.dat 162 347 Properties of SDSS quasars with Chandra limits
See also: VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010) J/ApJS/150/19 : ChaMP. I. First X-ray source catalog (Kim+, 2004) J/ApJS/155/73 : Photometric redshifts of X-ray sources in CDF-S (Zheng+, 2004) J/A+A/434/475 : Redshifts for X-ray selected AGNs (Kitsionas+, 2005) J/ApJ/618/123 : Hard X-ray-emitting AGNs (Silverman+, 2005) J/ApJS/169/401 : ChaMP X-ray point source catalog (Kim+, 2007) J/AJ/133/313 : AGN from RASS and SDSS DR5 (Anderson+, 2007) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 18 A18 --- ObjID SDSS-DR6 ObjID 20- 28 F9.5 deg RAdeg SDSS source right ascension (J2000) 30- 38 F9.6 deg DEdeg SDSS source declination (J2000) 40- 45 F6.3 mag imag SDSS i band PSF magnitude (dereddened) 47- 51 F5.3 --- zph Photometric redshift 53- 57 F5.3 --- pr(zph) [0,1] Photometric redshift probability 59- 63 F5.3 --- zph0 Photometric redshift lower limit 65- 69 F5.3 --- zph1 Photometric redshift upper limit 71- 76 F6.4 --- zbest Best redshift 78 A1 --- r_zbest ? Reference if spectroscopic redshift (G1) 80- 95 A16 --- CXOMP ChaMP X-ray source name (JHHMMSS.s+DDMMSS) 97-109 A13 --- ChaMPid Internal ChaMP source ID (2) 111-114 F4.1 arcmin OAA Chandra off-axis angle 116-121 F6.1 ct Xct Net counts in the 0.3-8keV range 123-126 F4.1 --- e_Xct RMS uncertainty on Xct 128-132 F5.1 ks Exp Vignetting-corrected exposure time 134-137 F4.1 10+20cm-2 nHgal Galactic absorbing HI column density 139-142 F4.2 10+22cm-2 nHintr ? Best fit intrinsic absorbing HI column density 144-147 F4.2 10+22cm-2 nHup ? 90% upper error limit on nHintr 149-153 F5.2 10+22cm-2 nHlo ? 90% lower error limit on nHintr 155-159 F5.2 --- Gam X-ray photon energy index Γ 161-164 F4.2 --- Gam.up 90% lower error limit on Γ 166-171 F6.2 --- Gam.lo 90% lower error limit on Γ 173-179 F7.3 [mW/m2] Fxb 0.5-8keV flux in erg/cm2/s (log10) 181-186 F6.3 [10-7W] logLx 2keV luminosity in erg/s (log10) 188-193 F6.3 [10-7W] logL2500 2500Å luminosity in erg/s (log10) 195-199 F5.3 --- aox Optical/X-ray Spectral index (G3) 201-207 F7.2 mJy F20cm ? 1.4GHz FIRST radio flux density (3) 209 I1 --- n_F20cm [0/1] 1 if multiple/extended radio morphology 211-215 F5.2 mag RL Radio loudness (G4) 217 I1 --- Cl [0/3] Spectral classification (G5) 219 I1 --- Target [0/1] is source a Chandra PI target? 221-272 A52 --- Comm Comments
Note (2): ChaMP internal X-ray source name, in format XSoooooBc_nnn where oooo = Chandra obsid, c = ACIS CCD ID, and nnn = source number on that CCD. Note (3): Summed flux from multiple FIRST sources or NVSS.
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 18 A18 --- ObjID SDSS-DR6 ObjID 20- 28 F9.5 deg RAdeg SDSS source right ascension (J2000) 30- 38 F9.6 deg DEdeg SDSS source declination (J2000) 40- 45 F6.3 mag imag SDSS i band PSF magnitude (dereddened) 47- 51 F5.3 --- zph Photometric redshift 53- 57 F5.3 --- pr(zph) Photometric redshift probability 59- 63 F5.3 --- zph0 Photometric redshift lower limit 65- 69 F5.3 --- zph1 Photometric redshift upper limit 71- 76 F6.4 --- zbest Best redshift (G1) 78 A1 --- r_zbest [S ] Reference if spectroscopic redshift (G1) 80- 83 I4 --- ObsID Chandra observation ID 85 I1 --- ccdid ACIS CCD ID 87- 90 F4.1 arcmin OAA Chandra off-axis angle 92- 95 F4.1 ct Xlim 90% Counts upper limit the 0.3-8keV range (1) 97-101 F5.1 ks Exp Vignetting-corrected exposure time 103-106 F4.1 10+20cm-2 nHgal Galactic absorbing HI column density (G2) 108-114 F7.3 [mW/m2] Fxb Upper limit 0.5-8keV flux in erg/cm2/s (log10) 116-121 F6.3 [10-7W] logLx upper limit 2keV luminosity in erg/s (log10) 123-128 F6.3 [10-7W] logL2500 2500Å luminosity in erg/s (log10) 130-134 F5.3 --- aox Lower limit to optical/X spectral index (G3) 136-139 F4.2 mJy F20cm ? 1.4GHz integrated flux density from FIRST 141-144 F4.2 mag RL Radio loudness (G4) 146 I1 --- Cl [0,3] Spectral classification (G5) 148-162 A15 --- Comm Comments
Note (1): Number of (0.3-8keV) counts that would be detected 90% of the time at this OAA and exposure on this CCD.
Global Notes: Note (G1): If zbest is different than zphot, it is a spectroscopic redshift. References are: S = SDSS DR6 spectrum and redshift O = ChaMP spectrum and redshift R = redshift/class from NED reference Note (G2): from Dickey & Lockman, 1990ARA&A..28..215D Note (G3): αox=0.3838+log(L2500/Lx). See section 6 for further details. Note (G4): RL=0.4(imag-m20cm), where * m20cm is the radio AB magnitude, m20cm=-2.5log(F20cm/3631Jy) calculated from the integrated radio flux density. A value of 1mJy is assumed as an upper limit where there is no detected FIRST source. * imag is the SDSS i-band magnitude, corrected for Galactic extinction. Note (G5): Classification as follows: 1 = BAL (Broad absorption lines) identified by visual inspection of spectra, if available; 2 = NAL (Narrow absorption lines) identified by visual inspection of spectra, if available; 3 = NLS1: spectral measurement of FWHM(Hβ)<2000km/s.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 02-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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