J/ApJ/450/51 X-rays from large optical QSO sample (Green+ 1995)
The soft X-ray properties of a large optical QSO sample:
ROSAT observations of the Large Bright Quasar Survey
Green P.J., Schartel N., Anderson S.F., Hewett P.C.,
Foltz C.B., Brinkmann W., Fink H., Trumper J., Margon B.
<Astrophys. J. 450, 51 (1995)>
=1995ApJ...450...51G 1995ApJ...450...51G (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; X-ray sources
Mission_Name: ROSAT
Keywords: galaxies: active - quasars: general - surveys - X-rays: galaxies
Abstract:
Of the more than 1000 QSOs in the Large Bright Quasar Survey
(LBQS), we study the X-ray properties of 908 that were covered by the
ROSAT All-Sky Survey (RASS). These data constitute among the largest,
most homogeneous X-ray surveys of QSOs to date, and as such are well
suited to the study of the multiwavelength properties of QSOs. Due to
the ∼600 s RASS exposure times, only 10% of the QSOs are detected in
X-rays. However, by stacking X-ray counts, we obtain effectively much
more sensitive observations for an average QSO in bins of redshift or
luminosity, and for several classes of QSOs. We confirm a correlation
of alpha_ox (slope of a hypothetical power law connecting 2500A and
2keV) with luminosity for the overall sample. For higher redshifts and
optical luminosities, radio-loud QSOs appear to become progressively
more luminous in X-rays than radio-quiet QSOs. The X-ray properties of
a subsample of 36 broad absorption line QSOs suggest that they are
strongly absorbed or underluminous in the X-rays, while a subsample of
22 Fe II-strong QSOs is anomalously X-ray bright.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 94 908 Raw data and luminosities of detected
LBQS/RASS QSOs
tables.tex 146 987 AASTeX version of the table1 and table2
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See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (RASS) (Voges+ 1996)
Byte-by-byte Description of file: table1
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Name of the LBQS QSO
11- 16 F6.3 --- z Redshift
18- 22 F5.1 mag BJmag B_J magnitude
24- 28 F5.2 mag A(B) Extinction
30- 33 F4.1 10+20cm-2 NH Galactic hydrogen column density
35- 40 F6.1 --- Csrc RASS source counts
42- 45 F4.1 --- e_Csrc Csrc uncertainty
47- 51 F5.1 --- Cbkg RASS source counts normalized to the
source aperture area
53- 55 F3.1 --- e_Cbkg CBkg uncertainty
57- 62 F6.1 s ExpTime RASS exposure time
65 A1 --- l_log(LX) Lx limiting character
66- 70 F5.2 [10-7W] log(LX) Logarithm of X-ray luminosity
72- 77 F6.2 [10-7W] log(Lopt) Logarithm of optical luminosity
80 A1 --- l_Alp(oX) Alp(oX) limiting character
81- 84 F4.2 --- Alp(oX) Slope of a hypothetical power law
connecting 250nm and 2 keV
87- 94 A8 --- Notes *Notes
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Note on Notes:
RL Radio loud
RL * Radio loud, data from Molonglo Reference Catalog, Large et al.
(1981) Cat. VIII/16 or from Condon et al. (1994AJ....107.1829C 1994AJ....107.1829C)
RQ Radio quiet
RA Radio ambiguous, when a radio flux upper limit is consistent
with either a radio-loud or a radio-quiet designation
BAL Clear broad absorption lines
Fe Strong Fe II QSO
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Table2: WOR regressions of αox(log(lopt))
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Bin parameters No. of bins Slope Intercept
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Full RLBQS/RASS sample
N_H/log l_opt 1/20 0.09 ± 0.02 -1.4 ± 0.7
N_H/log l_opt 6/ 7 0.07 ± 0.02 -0.6 ± 0.5
N_H/log l_opt 5/ 5 0.08 ± 0.02 -0.9 ± 0.7
N_H/log l_opt 1/ 5 0.11 ± 0.03 -1.8 ± 0.9
N_H/Redshift 1/17 0.11 ± 0.01 -1.9 ± 0.4
N_H/Redshift 5/ 5 0.11 ± 0.02 -1.9 ± 0.7
N_H/Redshift 1/ 4 0.15 ± 0.01 -3.0 ± 0.2
Radio quiet sample
N_H/Redshift 1/ 4 0.15 ± 0.07 -3.1 ± 2.3
Radio loud sample
N_H/Redshift 1/ 4 0.00 ± 0.26 1.5 ± 8.1
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Origin: AAS CD-ROM series, Volume 4, 1995 Lee Brotzman [ADS] 10-Oct-95
(End) Patricia Bauer [CDS] 24-Oct-1996