J/MNRAS/383/1513 2MASS, SDSS and FIRST fluxes of QSOs (Labita+, 2008)
The near-infrared to ultraviolet continuum of radio-loud versus radio-quiet
quasars.
Labita M., Treves A., Falomo R.
<Mon. Not. R. Astron. Soc., 383, 1513-1518 (2008)>
=2008MNRAS.383.1513L 2008MNRAS.383.1513L
ADC_Keywords: QSOs ; Photometry, infrared ; Photometry, SDSS ; Redshifts
Keywords: galaxies: active - galaxies: nuclei- quasars: general
Abstract:
Starting from a sample of Sloan Digital Sky Survey quasars appearing
also in the Two-Micron All-Sky Survey, we study the continuum
properties of ∼1000 objects observed in eight bands, from
near-infrared to ultraviolet. We construct the mean spectral energy
distribution (SED) and compare and contrast the continua of radio-loud
and radio-quiet quasar (RLQ and RQQ, respectively) objects. The SEDs
of the two populations are significantly different, in the sense that
RLQs are redder with power-law spectral indices
<alphaRLQ≥0.55±0.04 and <alphaRQQ≥0.31±0.01 in the spectral
range between 1014.5 and 1015.35Hz. This difference is discussed
in terms of different extinctions, different disc temperatures, or
slopes of the non-thermal component.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 103 887 Monochromatic fluxes are derived from SDSS, 2MASS
and FIRST and corrected for Galactic extinction
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
VIII/71 : The FIRST Survey Catalog, Version 03Apr11 (Becker+ 2003)
http://www.sdss.org : SDSS Home Page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 F7.3 deg RAdeg Right ascension in decimal degrees (J2000)
9- 15 F7.3 deg DEdeg Declination in decimal degrees (J2000)
17- 21 F5.3 --- z Redshift
23- 29 E7.3 Jy Fu SDSS u band flux
31- 37 E7.3 Jy Fg SDSS g band flux
39- 45 E7.3 Jy Fr SDSS r band flux
47- 53 E7.3 Jy Fi SDSS i band flux
55- 61 E7.3 Jy Fz SDSS z band flux
63- 69 E7.3 Jy FJ 2MASS J band flux
71- 77 E7.3 Jy FH 2MASS H band flux
79- 85 E7.3 Jy FK 2MASS K band flux
87 A1 --- l_F20cm Limit flag on F20cm
88- 94 E7.3 Jy F20cm FIRST 20cm flux
96 A1 --- l_R(r-o) Limit flag on R(r-o)
97-103 F7.2 --- R(r-o) Ratio between radio and optical fluxes (1)
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Note (1): The distinction between RLQ and RQQ objects is usually made
referring to the ratio between the radio and optical flux. Here,
we assume that a quasi-stellar object (QSO) is radio loud if
R(r-o)=[Fnu(1.5x109Hz)]/[Fnu(6x1014Hz]>10 (20cm/0.5µm)
and radio quiet otherwise.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 05-May-2008