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J/ApJ/842/87           Radio luminosity function of FSRQs           (Mao+, 2017)

Radio luminosity function of flat-spectrum radio quasars. Mao P., Urry C.M., Marchesini E., Landoni M., Massaro F., Ajello M. <Astrophys. J., 842, 87 (2017)> =2017ApJ...842...87M
ADC_Keywords: QSOs ; Redshifts ; Radio sources ; Spectra, optical Keywords: cosmology: observations; galaxies: active; galaxies: jets; quasars: general Abstract: We present the radio luminosity function (LF) of flat-spectrum radio quasars (FSRQ), using the largest and most complete sample to date. Cross-matching between the FIRST 20cm and GB6 6cm radio surveys, we find 638 flat-spectrum radio sources above 220mJy at 1.4GHz; of these, 327 are classified and verified using optical spectroscopy data, mainly from Sloan Digital Sky Survey Data Release 12. We also considered flat-spectrum radio sources that lack both literature references and optical spectroscopy, and we identified 12 out of the 43 such sources to potentially be FSRQs, using their WISE colors. From the fully identified sample of 242 FSRQs, we derived the radio LF and cosmic evolution of blazars at 1.4GHz, finding good agreement with previous work at 5GHz. The number density of FSRQs increases dramatically to a redshift of z∼2 and then declines for higher redshifts. Furthermore, the redshift at which the quasar density peaks is clearly dependent on luminosity, with more luminous sources peaking at higher redshifts. The approximate best-fit LF for a luminosity-dependent evolutionary model is a broken power-law with slopes ∼0.7 and ∼1.7 below and above the break luminosity, logL1.4∼43.8erg/s, respectively. Description: To build the largest sample of flat-spectrum radio quasars, we started with the radio catalog of the Faint Images of the Radio Sky at Twenty Centimeter (FIRST) survey (Helfand+ 2015, VIII/92), which covered 10575deg2 of the sky; and the Green Bank 6cm (GB6) Radio Source Catalog (Gregory+ 1996, VIII/40), which covered 17000deg2 of the sky. We cross-matched the radio position of each FIRST source with sources in the GB6 catalog, taking into account the positional uncertainties of both radio surveys. Of the 638 radio sources with flat radio spectra, 327 have an optical spectrum available in the literature, 266 from SDSS and the rest from various other sources identified through the NASA Extragalactic Database (NED). Out of the 327 objects with optical spectra classified, 200 were classified as FSRQs (of which 168 are free from contamination), 26 were classified as BL Lacs, 38 were classified as Seyferts, 41 were classified as Galaxies, 2 were classified as stars, and 12 and 8 indicated as noisy or uncertain, respectively. An additional 85 quasars (of which 74 are free from contamination) out of the 119 with a literature description were also included in the inclusive sample. See section 2 for more details on the sample selection. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 86 242 Complete data for the radio-flux-limited sample of flat spectrum sources table3.dat 33 12 Sources with unknown classification predicted to be flat-spectrum radio quasars (FSRQs)
See also: VIII/5 : Bright Extragalactic Radio Sources (1Jy) (Kuehr+, 1981) VIII/40 : GB6 catalog of radio sources (Gregory+ 1996) VIII/59 : the FIRST Survey, version 1999Jul (White+ 1999) V/139 : The SDSS Photometric Catalog, DR9 (Adelman-McCarthy+, 2012) V/147 : The SDSS Photometric Catalog, DR12 (Alam+, 2015) VIII/92 : The FIRST Survey Catalog, Version 2014Dec17 (Helfand+ 2015) VII/274 : The Roma BZCAT - 5th edition (Massaro+, 2015) J/A+AS/109/267 : Radio to X-Ray distribution of BL Lac Objects (Giommi+, 1995) J/ApJS/123/79 : Third EGRET catalog (3EG) (Hartman+, 1999) J/A+A/401/927 : The HRX-BL Lac sample (Beckmann+, 2003) J/A+A/445/465 : ATCA 18.5 and 22GHz fluxes of Kuehr 5GHz sample (Ricci+, 2006) J/ApJS/171/61 : All-Sky Survey of Flat-Spectrum Radio Sources (Healey+, 2007) J/ApJ/699/603 : Evolution of Swift/BAT blazars (Ajello+, 2009) J/A+A/508/107 : WMAP3 catalogue (Giommi+, 2009) J/ApJ/748/68 : WISE IR colors of gamma-ray blazars (D'Abrusco+, 2012) J/ApJ/772/26 : AGN with WISE. II. The NDWFS Bootes field (Assef+, 2013) J/ApJS/206/12 : Blazars with γ-ray counterparts. I. (D'Abrusco+, 2013) J/ApJS/207/4 : Unidentified γ-ray sources. III. Radio (Massaro+, 2013) J/ApJS/209/10 : UGSs. V. kernel approach (Massaro+, 2013) J/ApJS/206/13 : Blazars with γ-ray counterparts. II. (Massaro+, 2013) J/ApJS/215/14 : WISE cand. γ-ray blazar radio sources (D'Abrusco+, 2014) J/ApJS/213/3 : Low-frequency flat spectrum sources (LORCAT) (Massaro+, 2014) J/A+A/588/A141 : The MWA view of Fermi blazars (Giroletti+, 2016) J/ApJS/224/26 : SEDs of Roma BZCAT blazars (Mao+, 2016) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 5 A5 --- --- [FIRST] 6- 21 A16 --- FIRST FIRST identifier (JHHMMSS.s+DDMMSS) (G1) 23- 25 A3 --- --- [GB6] 27- 37 A11 --- GB6 GB6 identifier (JHHMM+DDMMA) (1) 39- 46 F8.4 deg RAdeg Right ascension, decimal degrees (J2000) 48- 54 F7.4 deg DEdeg Declination, decimal degrees (J2000) 56- 61 F6.4 --- zspec [0.04/5.3]? Spectroscopic redshift 63- 65 A3 --- Class Source Classification (2) 67- 69 A3 --- Clean Clean identification (3) 71- 77 F7.4 --- alpha [-1.2/0.5] SED slope 79- 86 F8.3 mJy Fint [220/6599] Integrated flux at 1.4GHz
Note (1): Green Bank 6-cm (GB6) Radio Source Catalog, Gregory+ (1996, VIII/40). Note (2): Source Classification. Capital letters indicate classification done via inspecting the optical spectrum, while small letters indicate classification obtained through literature. Class as follows: QSO = quasar (168 occurrences); qso = quasar? (74 occurrences); Note (3): Clean if the source spectrum was optically verified.
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 5 A5 --- --- [FIRST] 6- 21 A16 --- FIRST FIRST identifier (JHHMMSS.s+DDMMSS) (G1) 23- 26 F4.2 --- z [0.7/1.8] Redshift (1) 28- 33 F6.2 mJy Fint [221/596] Integrated flux at 1.4GHz
Note (1): The redshifts are estimated from the redshifts of similar FSRQs using the K-Nearest Neighbor (KNN) algorithm.
Global notes: Note (G1): Faint Images of the Radio Sky at Twenty centimeter (FIRST) survey, Helfand+ (2015, VIII/92).
History: From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 30-Jan-2018
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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