J/ApJS/201/10 SDSS quasar catalog with Swift observations (Wu+, 2012)
A quasar catalog with simultaneous UV, optical, and X-ray observations by Swift.
Wu J., Vanden Berk D., Grupe D., Koch S., Gelbord J., Schneider D.P.,
Gronwall C., Wesolowski S., Porterfield B.L.
<Astrophys. J. Suppl. Ser., 201, 10 (2012)>
=2012ApJS..201...10W 2012ApJS..201...10W
ADC_Keywords: QSOs ; Photometry, ultraviolet ; Photometry, UBV ; X-ray sources ;
Photometry, SDSS ; Active gal. nuclei
Keywords: catalogs - galaxies: active - galaxies: nuclei - quasars: general -
ultraviolet: galaxies - X-rays: galaxies
Abstract:
We have compiled a catalog of optically selected quasars with
simultaneous observations in UV/optical and X-ray bands by the Swift
Gamma-ray Burst Explorer. Objects in this catalog are identified by
matching the Swift pointings with the Sloan Digital Sky Survey Data
Release 5 quasar catalog. The final catalog contains 843 objects,
among which 637 have both Ultraviolet Optical Telescope (UVOT) and
X-Ray Telescope (XRT) observations and 354 of which are detected by
both instruments. The overall X-ray detection rate is ∼60% which
rises to ∼85% among sources with at least 10ks of XRT exposure time.
We construct the time-averaged spectral energy distribution (SED) for
each of the 354 quasars using UVOT photometric measurements and XRT
spectra. From model fits to these SEDs, we find that the big blue bump
contributes about ∼0.3 dex to the quasar luminosity. We re-visit the
αox-L2500Å relation by selecting a clean sample with only
Type 1 radio-quiet quasars; the dispersion of this relation is reduced
by at least 15% compared with studies that use non-simultaneous
UV/optical and X-ray data.
Description:
The raw sample is constructed by matching 3.5 years Swift pointings
and the SDSS DR5 quasar catalog (Cat. VII/252, superseded by
Cat. VII/260) and contains 1034 objects. Our final catalog contains
843 quasars with 0.0129≤z≤4.5766 and -30.24≲iMag≲-22.01.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table8.dat 449 1034 SDSS quasar catalog with Swift observations
--------------------------------------------------------------------------------
See also:
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
J/ApJ/728/23 : GALEX UV-bright high-redshift quasars (Worseck+, 2011)
J/ApJ/726/20 : X-ray emission from quasars (Miller+, 2011)
J/A+A/520/A47 : Blazars in the Swift-BAT hard X-ray sky (Maselli+, 2010)
J/AJ/140/1987 : SDSS-GALEX QSO catalog (Hutchings+, 2010)
J/ApJ/699/603 : Evolution of Swift/BAT blazars (Ajello+, 2009)
J/AJ/137/3761 : Ultraviolet quasi-stellar objects (Bianchi+, 2009)
J/ApJS/183/17 : The SDSS DR5/XMM-Newton quasar survey (Young+, 2009)
J/ApJ/685/773 : X-ray-UV relations in SDSS DR5 QSOs (Gibson+, 2008)
J/MNRAS/382/412 : SDSS-DR5/2MASS spectroscopic quasars (Ofek, 2007)
Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- SDSS SDSS DR5 designation
(HHMMSS.ss+DDMMSS.s; J2000)
20- 29 F10.6 deg RAdeg SDSS Right Ascension (J2000)
31- 40 F10.6 deg DEdeg SDSS Declination (J2000)
42- 47 F6.4 --- z [0/4.6] SDSS DR5 quasar catalog redshift
49- 54 F6.2 mag iMag ?=0 SDSS DR5 quasar catalog absolute
i band magnitude
56- 61 F6.3 mag umag ?=0 BEST PSF u band magnitude (1)
63 A1 --- Q [a-d] Data quality flag (2)
65 I1 --- C [0/1] Catalog flag (1=in final catalog)
67 I1 --- SED [0/1] SED flag (1=has SED plots)
69 I1 --- N2M [0/3] Number of 2MASS photometric data
points
71 I1 --- NUV [0/6] Number of Swift/UVOT photometric
data points
73 A1 --- X [agow] Quality of XRT data, g=good (3)
75- 80 A6 --- QSO Classification of quasar (10)
82 A1 --- Xmod ?=-[a-d] Model used to fit XRT spectrum
(4)
84- 85 I2 --- Rf [-1/1] Red flag (1=color is "red"; see
section 3.6)
87 I1 --- Sf [0/1] SDSS fit flag (1=SDSS spectrum is
fit)
89- 95 F7.3 --- Gamma ?=-99.9 Photon index Γ between
0.3 and 10keV
97-103 F7.3 --- e_Gamma ?=-99.9 1σ lower error on Gamma
105-111 F7.3 --- E_Gamma ?=-99.9 1σ upper error on Gamma
113-119 F7.3 --- HR ?=-99.9[0.008/1] Hardness ratio (5)
121-127 F7.3 [mW/m2] logFo ?=-99.9 Log of observed 0.3-10keV flux;
erg/s/cm2
129-135 F7.3 [mW/m2] logFu ?=-99.9 Log of unabsorbed 0.3-10keV
flux; erg/s/cm2
137-143 F7.3 [10-7W/Hz] logL2 ?=-99.9 Log of 2keV monochromatic
luminosity; erg/s/Hz
145-151 F7.3 [10-7W/Hz] e_logL2 ?=-99.9 The 1σ error in logL2
153-159 F7.3 [10-7W] logL ?=-99.9 Integrated 0.3-10keV luminosity;
erg/s
161-162 I2 --- Xdet [-1/1] XRT detection flag (6)
164-172 E9.3 ct/ks CR ?=-99.9 Source count rate
174-181 F8.1 s Xexp Total XRT exposure time
183-187 F5.3 10+20/cm2 NHg [0.006/0.123] Galactic column density
189-195 F7.3 10+22/cm2 NHi ?=-99.9 Intrinsic column density
197-203 F7.3 10+22/cm2 e_NHi ?=-99.9 The 1σ NHi lower error bar
205-211 F7.3 10+22/cm2 E_NHi ?=-99.9 The 1σ NHi upper error bar
213-214 I2 --- Vfl [-1/1] UVOT/V band photometry flag (7)
216-223 F8.1 s Vexp Total Swift UVOT V band exposure time
225-231 F7.3 [10-19W/m2/nm] logFV ?=-99.9 Log of Swift UVOT V band flux
density (8)
233-239 F7.3 [10-19W/m2/nm] e_logFV ?=-99.9 The 1σ error in logFV
241-242 I2 --- Bfl [-1/1] UVOT/B band photometry flag (7)
244-250 F7.1 s Bexp Total Swift UVOT B band exposure time
252-258 F7.3 [10-19W/m2/nm] logFB ?=-99.9 Log of Swift UVOT B band flux
density (8)
260-266 F7.3 [10-19W/m2/nm] e_logFB ?=-99.9 The 1σ error in logFB
268-269 I2 --- Ufl [-1/1] Swift U band photometry flag (7)
271-277 F7.1 s Uexp Total Swift UVOT U band exposure time
279-285 F7.3 [10-19W/m2/nm] logFU ?=-99.9 Log of Swift UVOT U band flux
density (8)
287-293 F7.3 [10-19W/m2/nm] e_logFU ?=-99.9 The 1σ error in logFU
295-296 I2 --- W1fl [-1/1] Swift UVOT UVW1 band photometry
flag (7)
298-305 F8.1 s W1exp Total Swift UVOT UVW1 band exposure time
307-313 F7.3 [10-19W/m2/nm] logFW1 ?=-99.9 Log of Swift UVOT UVW1 band flux
density (8)
315-321 F7.3 [10-19W/m2/nm] e_logFW1 ?=-99.9 The 1σ error in logFW1
323-324 I2 --- M2fl [-1/1] Swift UVM2 band photometry
flag (7)
326-333 F8.1 s M2exp Total Swift UVOT UVM2 band exposure time
335-341 F7.3 [10-19W/m2/nm] logFM2 ?=-99.9 Log of Swift UVOT UVM2 band flux
density (8)
343-349 F7.3 [10-19W/m2/nm] e_logFM2 ?=-99.9 The 1σ error in logFM2
351-352 I2 --- W2fl [-1/1] Swift UVW2 band photometry
flag (7)
354-361 F8.1 s W2exp Total Swift UVOT UVW1 band exposure time
363-369 F7.3 [10-19W/m2/nm] logFW2 ?=-99.9 Log of Swift UVOT UVW2 band flux
density (8)
371-377 F7.3 [10-19W/m2/nm] e_logFW2 ?=-99.9 The 1σ error in logFW2
379-385 F7.3 --- alpha ?=-99.9 UV spectral index α by
fitting photometric data
387-393 F7.3 --- e_alpha ?=-99.9 The 1σ error in alpha
395-401 F7.3 [10-7W/Hz] logLUV ?=-99.9 Log of 2500Å monochromatic
luminosity; erg/s/Hz
403-409 F7.3 [10-7W/Hz] e_logLUV ?=-99.9 The 1σ error in logLUV
411-417 F7.3 --- alphaox ?=-99.9 Spectral index using logL2 and
logLUV αox
419-425 F7.3 --- e_alphaox ?=-99.9 The 1σ error in alphaox
427-433 F7.3 Msun MBH ?=-99.9 Black hole mass (9)
435-441 F7.3 [mW/m2] logLEXP ?=-99.9 Log bolometric luminosity in
exponential decay model (EXP); erg/s
443-449 F7.3 [mW/m2] logLTPL ?=-99.9 Log bolometric luminosity in
triple power-law model (TPL); erg/s
--------------------------------------------------------------------------------
Note (1): Corrected for Galactic extinction.
Note (2): We classify objects in the database into four types based on data
availability as follows:
a = 637 objects that have useful data from both UVOT and XRT. Among them,
345 are detected by UVOT and XRT.
b = 38 objects that have useful data from UVOT but not XRT. These objects
cannot be included in correlation analysis.
c = 168 objects that have only useful data from XRT but not UVOT. We will
only create the XRT energy spectra for these objects.
d = 191 objects that are bereft of any useful data from UVOT or XRT. They
are not included in the final catalog.
Note (3): X-ray quality flag based on the total number of background-substracted
X-ray counts, NXph as follows:
g = good with NXph>100
a = acceptable with 10<NXph≤100
w = weak with NXph≤10
o = out of FOV
See section 2.1 for more XRT data explanations.
Note (4): Models A-D are presented in table 2 as below:
------------------------------------------------------
Model αX NH,i Objects Percentage
------------------------------------------------------
A Fixed to -1 Fixed to 0 177 44%
B Free Fixed to 0 195 49%
C Free Free 15 4%
D Fixed to -1 Free 12 3%
------------------------------------------------------
Note (5): Where HR=(H-S)/(H+S) where H is the X-ray photon count between
1 and 10keV and S is the X-ray photon count between 0.3 and 1keV.
Note (6): Flag as follows:
1 = detection;
0 = non-detection;
-1 = not observed.
Note (7): Flag as follows:
1 = has Swift photometry in this band;
-1 = Does not have Swift photometry in this band.
Note (8): In units of 10-17erg/s/cm2/Angstrom and corrected for
Galactic reddening.
Note (9): Calculated using emission line FWHM and corresponding continuum flux
calculated by power-law fitting of photometric data points.
Note (10): classes (in addition to QSO and Sy) are:
BALQ = Broad Absorption Lines QSO
BLLAC = BL Lac object
DUSTRE = dust reddened
LENS = lensed quasar
NLS1 = Narrow-line Seyfert 1
RL = Radio-loud QSO
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Nov-2012