J/MNRAS/492/719 Chandra observations of 2106 radio-quiet QSOs (Timlin+, 2020)
The correlations between optical/UV broad lines and X-ray emission from a large
sample of quasars.
Timlin J., Brandt W.N., Ni Q., Luo B., Schneider D., Vivek M., Yi W.
<Mon. Not. R. Astron. Soc. 492, 719 (2020)>
=2020MNRAS.492..719T 2020MNRAS.492..719T (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; X-ray sources ; Photometry, SDSS ; Equivalent widths
Keywords: galaxies: active - quasars: emission lines - quasars: general -
X-rays: general
Abstract:
We present Chandra observations of 2106 radio-quiet quasars in the
redshift range 1.7≤z≤2.7 from the Sloan Digital Sky Survey
(SDSS), through data release fourteen (DR14, 2018ApJS..235...42A 2018ApJS..235...42A),
that do not contain broad absorption lines (BAL) in their rest-frame
UV spectra. This sample adds over a decade worth of SDSS and Chandra
observations to our previously published sample of 139 quasars from
SDSS DR5 which is still used to correlate X-ray and optical/UV
emission in typical quasars. We fit the SDSS spectra for 753 of the
quasars in our sample that have high-quality (large exposure time and
small off-axis observation angle) X-ray observations, and analyze
their X-ray properties (aox and daox) with respect to the measured CIV
and MgII emission-line rest-frame equivalent width (EW) and the CIV
emission-line blueshift. We find significant correlations (at the
≥99.99% level) between aox and these emission-line parameters, as
well as between daox and CIV EW. Slight correlations are found between
daox and CIV blueshift, MgII EW, and the ratio of CIV EW to MgII EW.
The best-fit trend in each parameter space is used to compare the
X-ray weakness (daox) and optical/UV emission properties of typical
quasars and weak-line quasars (WLQs). The WLQs clearly deviate from
the expectation for every relationship, typically exhibiting much
weaker X-ray emission than predicted by the typical quasar
relationships. The best-fit relationships for our typical quasars are
consistent with predictions from the disk-wind quasar model. The
behavior of the WLQs with respect to our typical quasars can be
explained by an X-ray shielding model.
Description:
We assembled a large sample of 2106 quasars from the full SDSS quasar
archive (through DR14) that were serendipitously observed with Chandra
and are within the redshift range 1.7≤z≤2.7.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 1380 2106 Catalog
catalog.fits 2880 558 fits version of the catalog
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See also:
http://skyserver.sdss.org/DR14 : SDSS DR14 Home Page
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- SDSS SDSS Name (SDSS_Name)
20- 35 F16.12 deg RAdeg Right Ascension (J2000) (RA)
37- 54 F18.14 deg DEdeg [-10.6/69.7]? Declination (J2000)
(DEC)
56- 68 F13.11 --- z [1.7/2.7]? Redshift (Z)
70- 82 F13.10 [cm-2] logNH [19.6/21.2]? Galactic column
density (LOGNH)
84- 91 F8.4 mag IMAGZ2 [-30.0/-21.0]? Absolute Magnitude
(corrected to z=2) (MI_Z2)
93- 99 A7 --- ObsID Chandra observation ID (ObsID)
101- 115 F15.12 arcmin Theta [0.1/19.4]? Chandra offaxis angle
(THETA)
117- 132 F16.9 s ExpTimeS [737/170430]? Soft Band exposure
time (ExposureTimesoft)
134- 149 F16.9 s ExpTimeH [737/170430]? Hard Band exposure
time (ExposureTimehard)
151- 168 E18.12 --- PbSoft Binomial probability of detection
(soft band) (Pb_soft)
170- 187 E18.12 --- PbHard Binomial probability of detection
(hard band) (Pb_hard)
189- 204 F16.11 ct Soft-cts [1.9/1936.5]? Net soft-band
counts (Soft_Cts)
206- 220 F15.11 ct E_Soft-cts [2.3/115.3]? Positive error
(or upper limit) of net counts
(soft band) (Softctsperr)
222- 238 F17.13 ct e_Soft-cts [0.0/107.9]? Negative error
(or lower limit) of net counts
(soft band) (Softctsmerr)
240- 254 F15.11 ct Hard-cts [2.0/674.4]? Net hard-band counts
(Hard_cts)
256- 269 F14.11 ct E_Hard-cts [2.3/84.8]? Positive error
(or upper limit) of net counts
(hard band) (Hardctsperr)
271- 286 F16.13 ct e_Hard-cts [0.0/57.2]? Negative error
(or lower limit) of net counts
(hard band) (Hardctsmerr)
288- 303 F16.13 --- HR [0.0/29.8]? Hardness Ratio (HRat)
305- 321 F17.13 --- e_HR [0.0/784.5]? Negative error of
hardness ratio (HR_merr)
323- 339 F17.14 --- E_HR [0.0/28.9]? Positive error of
hardness ratio (HR_perr)
341- 343 F3.1 --- Gamma [0.5/3.0]? Power-law photon index
(both band detections) or limit
(single-band detection) (Gamma)
345- 348 F4.1 --- E_Gamma [-0.9/1.0]? Power-law photon
index positive error
(Gamma_perr)
350- 353 F4.1 --- e_Gamma [-0.4/0.6]? Power-law photon
index negative error (Gamma)
355- 371 E17.12 ct/s Soft-Count-rate Soft-band count rate
(SoftCountrate)
373- 389 E17.12 ct/s E_Soft-Count-rate Positive error on soft-band count
rate (SoftCountrate_perr)
391- 407 E17.12 ct/s e_Soft-Count-rate Negative error on soft-band count
rate (SoftCountrate_merr)
409- 418 E10.5 mW/m2 Soft-flux 0.5-2 keV flux (Soft_flux)
420- 429 E10.5 mW/m2 e_Soft-flux 0.5-2 keV flux lower limit
(Softfluxlolim)
431- 440 E10.5 mW/m2 E_Soft-flux 0.5-2 keV flux upper limit
(Softfluxuplim)
442- 458 E17.12 10-7J/cm2 F2kev Rest-frame 2 keV flux density
(f2kev)
460- 476 E17.12 10-7J/cm2 bF2kev Rest-frame 2 keV flux density
lower limit (f2kev_lolim)
478- 494 E17.12 10-7J/cm2 BF2kev Rest-frame 2 keV flux density
upper limit (f2kev_uplim)
496- 508 F13.10 [10-7W] logL210kev [43.2/46.3]? Rest-frame 2-10 keV
luminosity (logL_210kev)
510- 522 F13.10 [10-7W] blogL210kev [43.4/46.3]? Rest-frame 2-10 keV
luminosity lower limit
(logL210kevlolim)
524- 536 F13.10 [10-7W] BlogL210kev [42.8/46.2]? Rest-frame 2-10 keV
luminosity upper limit
(logL210kevuplim)
538- 554 E17.12 10-7J/cm2 F2500 Rest-frame 2500 Angstrom flux
density (f2500)
556- 568 F13.10 [10-7W] logL2500 [28.9/32.2]? Rest-frame 2500Å
luminosity density (logL_2500)
570- 584 F15.12 --- alphaox [-2.2/-0.4]? Observed alpha_ox
(alphaox)
586- 600 F15.12 --- balphaox [-2.1/-0.5]? Observed alpha_ox
lower limit (alphaox_lolim)
602- 616 F15.12 --- Balphaox [-2.4/-0.6]? Observed alpha_ox
upper limit (alphaox_uplim)
618- 636 E19.12 --- dalphaox Difference between observed
alpha_ox and the expectation
from alpha_ox-L2500 relation
(this work) (dalpha_ox)
638- 655 F18.15 --- dalphaoxJ07 [-0.5/0.8]? Difference between
observed alpha_ox and the
expectation from alpha_ox-L2500
relation (Just et al.,
2007ApJ...665.1004J 2007ApJ...665.1004J)
(dalphaoxJ07)
657- 675 E19.12 --- bdalphaox deltaalphaox lower limit
(dalphaoxlolim)
677- 694 E18.12 --- Bdalphaox deltaalphaox upper limit
(dalphaoxuplim)
696- 698 F3.1 --- ChipEdge [0/1]? If the Target overlapped
with the edge of the Chandra CCD
(1 for yes, 0 for no)
(CHIP_EDGE)
700- 709 A10 "date" Obs.Date Date of the Chandra observation,
iso-8601 (year)
711- 712 I2 --- ao [1.0/21.1]? Chandra observation
cycle (ao)
714 I1 --- multobs [0/1]? Observed more than once in
Chandra (1 for yes, 0 for no)
(multobs)
716- 719 I4 --- Plate [269/8874]? SDSS spectroscopic
Plate ID (PLATE)
721- 725 I5 --- MJD [51614/57520]? SDSS spectroscopic
MJD (MJD)
727- 729 I3 --- Fiber [1/999]? SDSS spectroscopic Fiber
ID (FIBER)
731- 743 F13.10 mag Umag0 [16.2/25.2]? Dereddend u-band
apparent magnitude from SDSS
(U_DERED) (1)
745- 757 F13.10 mag Gmag0 [16.0/23.0]? Dereddend g-band
apparent magnitude from SDSS
(G_DERED) (1)
759- 771 F13.10 mag Rmag0 [16.0/23.0]? Dereddend r-band
apparent magnitude from SDSS
(R_DERED) (1)
773- 785 F13.10 mag Imag0 [15.8/24.6]? Dereddend i-band
apparent magnitude from SDSS
(I_DERED) (1)
787- 799 F13.10 mag Zmag0 [15.6/23.5]? Dereddend z-band
apparent magnitude from SDSS
(Z_DERED) (1)
801- 803 I3 --- SDSSDR [71.0/142.1]? SDSS catalog in
which the target was found
(SDSS_DR)
805 I1 --- BALFlag [0/2]? Flag for detected broad
absorption lines
(BAL_FLAG) (2)
807- 808 I2 --- FIRSTFlag [-1/1]? Flag indicating if the
source was detected in FIRST
(FIRST_flag) (3)
810- 827 F18.15 mag Dg-i [-2.1/0.5]? SDSS g-i color
relative to the mean (DELTAGI)
829 I1 --- FlagTexp-theta [0/1]? Flag which indicates if
the target passed the exposure
time -- offaxis angle cut
(1= passed, 0=did not pass)
(FlagTexptheta)
831- 846 F16.12 --- SNRcont [-1.0/41.9]? Measured
signal-to-noise of the line free
continuum regions (SNR_cont)
848- 861 F14.10 [107J/cm2] logf2500 [-29.3/-1.0]? logarithm of
rest-frame 2500Å flux density
measured from the spectrum
(logf2500)
863- 878 F16.11 0.1nm CIV-EW [-1.0/857.2]? Rest-frame
equivalent width of the CIV
broad emission line measured
directly from the spectrum
(CIV_EW)
880- 896 F17.12 0.1nm e_CIV-EW [-1.0/160.3]? Measurement error
of rest-frame equivalent width
of the CIV broad emission line
measured directly from the
spectrum (CIVEWERR)
898- 913 F16.11 0.1nm CIV-EW-MOD [-1.0/960.4]? Rest-frame
equivalent width of the CIV
broad emission line measured
from the Gaussian models
(CIVEWMOD)
915- 931 F17.12 0.1nm e_CIV-EW-MOD [-1.0/165.8]? Measurement error
of rest-frame equivalent width
of the CIV broad emission line
measured from the Gaussian
models (CIVEWMOD_ERR)
933- 946 F14.8 km/s sigCIV-LINE [-1.0/5177.3]? Line dispersion of
the CIV broad emission line
(CIVLINESIGMA)
948- 961 F14.8 0.1nm CIV-peak [-1.0/1569.7]? Measured
rest-frame peak of the CIV broad
emission line (CIV_peak)
963- 978 F16.12 0.1nm e_CIV-peak [-1.0/15.6]? Uncertainty in the
measured rest-frame peak of the
CIV broad emission line
(CIVpeakERR)
980- 994 F15.8 km/s CIV-FWHM [-1.0/22740.7]? Full Width Half
Maximum of the modeled CIV broad
emission line (CIV_FWHM)
996-1011 F16.9 km/s e_CIV-FWHM [-1.0/10596.8]? Uncertainty in
Full Width Half Maximum of the
modeled CIV broad emission line
(CIVFWHMERR)
1013-1028 F16.12 --- CIV-LINE-SNR [-1.0/32.9]? Median
Signal-to-Noise ratio of the CIV
broad emission line
(CIVLINESNR)
1030-1044 F15.10 0.1nm CIII-EW [-999.0/457.5]? Rest-frame
equivalent width of the CIII
broad emission line measured
directly from the spectrum
(CIII_EW)
1046-1062 F17.12 0.1nm e_CIII-EW [-999.0/231.1]? Measurement error
of rest-frame equivalent width
of the CIII broad emission line
measured directly from the
spectrum (CIIIEWERR)
1064-1078 F15.10 0.1nm CIII-EW-MOD [-999.0/310.3]? Rest-frame
equivalent width of the CIII
broad emission line measured
from the Gaussian models
(CIIIEWMOD)
1080-1096 F17.12 0.1nm e_CIII-EW-MOD [-999.0/193.8]? Measurement error
of rest-frame equivalent width
of the CIII broad emission line
measured from the Gaussian
models (CIIIEWMOD_ERR)
1098-1111 F14.8 km/s sigCIII-LINE [-999.0/6510.0]? Line dispersion
of the CIII broad emission line
(CIIILINESIGMA)
1113-1126 F14.8 0.1nm CIII-peak [-999.0/1937.7]? Measured
rest-frame peak of the CIII
broad emission line (CIII_peak)
1128-1144 F17.12 0.1nm e_CIII-peak [-999.0/20.0]? Uncertainty in the
measured rest-frame peak of the
CIII broad emission line
(CIIIpeakERR)
1146-1160 F15.8 km/s CIII-FWHM [-999.0/37018.4]? Full Width Half
Maximum of the modeled CIII
broad emission line (CIII_FWHM)
1162-1176 F15.9 km/s e_CIII-FWHM [-999.0/8300.5]? Uncertainty in
Full Width Half Maximum of the
modeled CIII broad emission line
(CIIIFWHMERR)
1178-1194 F17.12 --- CIII-LINE-SNR [-999.0/37.9]? Median
Signal-to-Noise ratio of the
CIII broad emission line
(CIIILINESNR)
1196-1211 F16.10 0.1nm MgII-EW [-999.0/9357.6]? Rest-frame
equivalent width of the MgII
broad emission line measured
directly from the spectrum
(MgII_EW)
1213-1229 F17.12 0.1nm e_MgII-EW [-999.0/293.5]? Measurement error
of rest-frame equivalent width
of the MgII broad emission line
measured directly from the
spectrum (MgIIEWERR)
1231-1245 F15.10 0.1nm MgII-EWMOD [-999.0/617.3]? Rest-frame
equivalent width of the MgII
broad emission line measured
from the Gaussian models
(MgIIEWMOD)
1247-1263 F17.12 0.1nm e_MgII-EWMOD [-999.0/140.6]? Measurement error
of rest-frame equivalent width
of the MgII broad emission line
measured from the Gaussian
models (MgIIEWMOD_ERR)
1265-1278 F14.8 km/s sigMgII-LINE [-999.0/5950.5]? Line dispersion
of the MgII broad emission line
(MgIILINESIGMA)
1280-1293 F14.8 0.1nm MgII-peak [-999.0/2804.0]? Measured
rest-frame peak of the MgII
broad emission line (MgII_peak)
1295-1312 E18.12 0.1nm e_MgII-peak []?=-999 Uncertainty in the
measured rest-frame peak of the
MgII broad emission line
(MgIIpeakERR)
1314-1328 F15.8 km/s MgII-FWHM [-999.0/35258.4]? Full Width Half
Maximum of the modeled MgII
broad emission line (MgII_FWHM)
1330-1345 F16.9 km/s e_MgII-FWHM [-999.0/11485.6]? Uncertainty in
Full Width Half Maximum of the
modeled MgII broad emission line
(MgIIFWHMERR)
1347-1363 F17.12 --- MgII-LINE-SNR [-999.0/30.3]? Median
Signal-to-Noise ratio of the
MgII broad emission line
(MgIILINESNR)
1365-1380 F16.12 --- RL [0.1/270.6]? Radio loudness
parameter, F6cm/F2500Å
(R6CM2500A)
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Note (1): using Schlafly et al., 2011ApJ...737..103S 2011ApJ...737..103S.
Note (2): Flag for detected broad absorption lines as follows:
0 = no line
1 = BAL
2 = mini-BAL
Note (3): Flag indicating if the source was detected in FIRST as follows:
-1 = target not covered by FIRST
0 = FIRST non-detection
1 = FIRST detected
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Acknowledgements:
John Timlin, jxt811(at)psu.edu
(End) Patricia Vannier [CDS] 03-Oct-2019