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J/ApJ/645/856       Beamed radio-intermediate quasars        (Wang+, 2006)

Evidence for a population of beamed radio-intermediate quasars. Wang T.-G., Zhou H.-Y., Wang J.-X., Lu Y.-J., Lu Y. <Astrophys. J., 645, 856-860 (2006)> =2006ApJ...645..856W
ADC_Keywords: QSOs ; Radio sources Keywords: galaxies: jets - quasars: general - radio continuum: galaxies Abstract: Whether radio-intermediate quasars possess relativistic jets as radio-loud quasars do is an important issue in the understanding of the origin of radio emission in quasars. In this paper, using the two-epoch radio data obtained during the Faint Images of the Radio Sky at Twenty cm (FIRST) and NRAO VLA Sky Survey (NVSS), we identified 89 radio-variable sources in the Sloan Digital Sky Survey (SDSS). Among them, more than half are radio-intermediate quasars (RL=f20cm/f2500Å<250). For all objects with available multiple-band radio observations, the radio spectra are either flat or inverted. The brightness temperature inferred from the variability is larger than the synchrotron self-Compton limit for a stationary source in 87 objects, indicating relativistic beaming. Considering the sample selection and the viewing angle effect, we conclude that relativistic jets probably exist in a substantial fraction of radio-intermediate quasars. Description: The sample was selected by cross-correlating the Third Data Release (DR3) of the SDSS Quasar Catalog (Schneider et al., 2005, Cat. VII/243) with the FIRST catalog (ver. 03Apr11; Becker et al., 1995, Cat. VIII/71) and NVSS catalog (Condon et al., 1998, Cat. VIII/65). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 107 86 Basic data of Radio Variable Quasars
See also: VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998) VIII/71 : The FIRST Survey Catalog, Version 03Apr11 (Becker+ 2003) VII/243 : SDSS quasar catalog. III. (Schneider+, 2005) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 2 I2 h RAh Hour of Right Ascension (J2000) 4- 5 I2 min RAm Minute of Right Ascension (J2000) 7- 11 F5.2 s RAs Second of Right Ascension (J2000) 13 A1 --- DE- Sign of the Declination (J2000) 14- 15 I2 deg DEd Degree of Declination (J2000) 17- 18 I2 arcmin DEm Arcminute of Declination (J2000) 20- 23 F4.1 arcsec DEs Arcsecond of Declination (J2000) 25- 30 F6.4 --- z Redshift 32- 37 F6.3 mag g'mag SDSS g' band magnitude 39- 43 F5.3 mag e_g'mag Uncertainty in g'mag 45- 50 F6.2 mJy SFIRST FIRST 20cm flux density 52- 55 F4.2 mJy e_SFIRST Uncertainty in SFIRST 57- 66 A10 --- FIRST.Date Date of FIRST observation, in YYYY/MM/DD (1) 68- 73 F6.2 mJy SNVSS NRAO VLA Sky Survey flux density 75- 79 F5.2 mJy e_SNVSS Uncertainty in SNVSS 81- 90 A10 --- NVSS.Date Date of NVSS observation, in YYYY/MM/DD (1) 92- 95 F4.2 [-] logRL Log of the radio loudness (see text) 97-101 F5.2 [K] logTb Log of the brightness temperature 103-107 F5.2 --- Doppler Doppler factor (see text)
Note (1): Day could not be present.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 05-Oct-2007
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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