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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 (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:
FileName Lrecl Records Explanations
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
See also: IX/10 : ROSAT All-Sky Bright Source Catalogue (RASS) (Voges+ 1996) Byte-by-byte Description of file: table1
Bytes Format Units Label Explanations
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
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) 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
Table2: WOR regressions of αox(log(lopt)) -------------------------------------------------------------------------------- Bin parameters No. of bins Slope Intercept -------------------------------------------------------------------------------- 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 Origin: AAS CD-ROM series, Volume 4, 1995 Lee Brotzman [ADS] 10-Oct-95
(End) Patricia Bauer [CDS] 24-Oct-1996
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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