J/PASJ/74/239 Radio dichotomy of active galactic nuclei (Xiao+, 2022)
The radio dichotomy of active galactic nuclei.
Xiao H., Zhu J., Fu L., Zhang S., Fan J.
<Publ. Astron. Soc. Jap., 74, 239-246 (2022)>
=2022PASJ...74..239X 2022PASJ...74..239X (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; QSOs ; Radio sources
Keywords: galaxies: active - galaxies: nuclei - quasars: general
Abstract:
The question of radio dichotomy in active galactic nuclei (AGNs) is
still in debate, even though it has been discussed for more than 40
years. In order to solve this old riddle, we collect a sample of AGNs
with optical B band and radio 6 cm wavelength data to analyze the
radio loudness log R. Our results indicate a separation of log
R=<1.37+/=0.02> between radio-loud (RL) AGNs and radio-quiet (RQ)
AGNs, suggesting the existence of an RL/RQ dichotomy. For the first
time, we suggest combining radio luminosity and radio loudness as a
double criterion to divide AGNs into RLs and RQs to avoid
misclassification problems that may happen in the single-criterion
scenario; we propose the double-criterion dividing line log
L6cm=-2.7logR+44.3 by using a machine-learning method. In addition,
the key point of the RL/RQ dichotomy is the origin of radio emission
for the two classes, and we suggest the radio emission from RLs and
RQs share the same origin, e.g., jets and mini-jets (aborted-jet or
outflow), through a correlation study between radio 6 cm luminosity
and optical B-band luminosity.
Description:
We compile 2943 sources (2120 quasars, 245 BL Lacs, 578 other AGNs)
with available radio 6cm flux density, apparent magnitudes in the V
band, and colours of B-V from Veron-Cetty and Veron (2010, Cat.
VII/258), and list them in table 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 54 2943 Radio sources of our sample
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See also:
VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Source name (1)
19 A1 --- Class [ABQ] Sources classification (1) (2)
21- 25 F5.3 --- z Redshift (1)
27- 32 F6.3 Jy F6cm Radio flux density at 6 cm (1)
34- 38 F5.2 mag Vmag Optical magnitude at V band (1)
40- 44 F5.2 mag B-V Color index of B-V (1)
46- 51 F6.4 mag E(B-V) Galaxy extinction
53- 54 A2 --- RClass [RL RQ] New classification at radio band
in this work (3)
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Note (1): From Veron-Cetty and Veron, 2010A&A...518A..10V 2010A&A...518A..10V, Cat. VII/258.
Note (2): Sources classification as follows:
Q = quasar
B = BL Lac
A = Active galaxy nucleus
Note (3): Radio classification as follows:
RL = radio loud AGN
RQ = radio quiet AGN
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 21-Sep-2022