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J/ApJ/445/62       Radio properties of optically selected quasars (Hooper+ 1995)

Radio properties of optically selected quasars. Hooper E.J., Impey C.D., Foltz C.B., Hewett P.C. <Astrophys. J. 445, 62 (1995)> =1995ApJ...445...62H
ADC_Keywords: QSOs ; Redshifts ; Radio sources Keywords: quasars general - radio continuum: galaxies - surveys Abstract: Approximately one-quarter (256 objects) of the Large Bright Quasar Survey (LBQS, Hewett et al., 1995, Cat. J/AJ/109/1498) has been observed with the VLA at 8.4GHz, resulting in 44 detections (17%) with a median 3σ noise limit of 0.29mJy. Quasars with radio luminosity detectable at this limit are under-represented at faint absolute blue magnitudes (MB≥-24), an effect which cannot be explained by a potential LBQS selection bias against quasars which have large radio luminosities and small optical luminosities. The radio-loud (8GHz luminosity >1025W/Hz) fraction is observed to change as a function of redshift and MB, for MB←24, although the causal variable is ambiguous. The description most consistent with the available data is that radio-loud fraction is approximately constant over the range -27.5<MB←24 and increases at brighter absolute magnitudes. The radio-loud fraction as a function of redshift reaches a local maximum at z∼1, and, aside from the effects of increased radio-loud fraction at bright MB, remains roughly constant to redshifts approaching 5. The log R8.4 distribution (radio-to-optical luminosity ratio) of the current LBQS sample may be bimodal, but the results of statistical tests are ambiguous, requiring a larger sample size to become definite. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 78 256 Radio and optical observations of LBQS quasars
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 10 A10 --- LBQS Source name 12- 16 F5.2 mag Bmag B magnitude 19- 23 F5.3 --- z Redshift 25- 30 F6.2 mag BMag Absolute B magnitude 33- 36 F4.2 mag e_BMag rms uncertainty on BMag 38 A1 --- l_S8.4GHz Limit flag on S8.4GHz 39- 45 F7.2 mJy S8.4GHz Flux density at 8.4GHz 47- 52 F6.3 mJy e_S8.4GHz ? rms uncertainty on S8.4GHz 54 A1 --- l_logLr/Lb Limit flag on logLr/Lb 55- 59 F5.2 --- logLr/Lb Ratio of 8.4GHz luminosity to optical luminosity averaged over the B passband 61- 64 F4.2 --- e_logLr/Lb ? rms uncertainty on logLr/Lb 68 A1 --- l_logLr Limit flag on logLr 69- 73 F5.2 [W/Hz] logLr Luminosity at 8.4GHz 75- 78 F4.2 [W/Hz] e_logLr ? rms uncertainty on logLr
History: * 25-Jul-1997: prepared via OCR at CDS. * 04-Jun-1988: two OCR errors where corrected, thanks to H. Andernach
(End) James Marcout, Patricia Bauer [CDS] 25-Jul-1997
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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