J/A+A/622/A11 LoTSS/HETDEX. Optical quasars. I. (Guerkan+, 2019)
LoTSS/HETDEX: Optical quasars.
I. Low-frequency radio properties of optically selected quasars.
Guerkan G., Hardcastle M.J., Best P.N., Morabito L.K., Prandoni I.,
Jarvis M.J., Duncan K.J., Calistro Rivera G., Callingham J.R.,
Cochrane R.K., Croston J.H., Heald G., Mingo B., Mooney S., Sabater J.,
Roettgering H.J.A., Shimwell T.W., Smith D.J.B., Tasse C., Williams W.L.
<Astron. Astrophys. 622, A11 (2019)>
=2019A&A...622A..11G 2019A&A...622A..11G (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; QSOs ; Radio sources
Keywords: quasars: general - galaxies: active - radio continuum: galaxies
Abstract:
The radio-loud/radio-quiet (RL/RQ) dichotomy in quasars is still an
open question. Although it is thought that accretion onto supermassive
black holes in the centre the host galaxies of quasars is responsible
for some radio continuum emission, there is still a debate as to
whether star formation or active galactic nuclei (AGN) activity
dominate the radio continuum luminosity. To date, radio emission in
quasars has been investigated almost exclusively using high-frequency
observations in which the Doppler boosting might have an important
effect on the measured radio luminosity, whereas extended structures,
best observed at low radio frequencies, are not affected by the
Doppler enhancement. We used a sample of quasars selected by their
optical spectra in conjunction with sensitive and high-resolution
low-frequency radio data provided by the LOw Frequency ARray (LOFAR)
as part of the LOFAR Two-Metre Sky Survey (LoTSS) to investigate their
radio properties using the radio loudness parameter
(R=L144MHz/Liband). The examination of the Li band radio continuum
emission and RL/RQ dichotomy in quasars exhibits that quasars show a
wide continuum of radio properties (i.e. no clear bimodality in the
distribution of R). Radio continuum emission at low frequencies in
low-luminosity quasars is consistent with being dominated by star
formation. We see a significant albeit weak dependency of R on the
source nuclear parameters. For the first time, we are able to resolve
radio morphologies of a considerable number of quasars. All these
crucial results highlight the impact of the deep and high-resolution
low-frequency radio surveys that foreshadow the compelling science
cases for the Square Kilometre Array (SKA).
Description:
Low-frequency radio continuum, far-infrared measurements and derived
of properties of SDSS quasars over the HETDEX and H-ATLAS/NGP regions.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 262 49925 Measured properties of SDSS quasars
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See also:
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
J/ApJS/228/9 : Physical parameters of ∼300000 SDSS-DR12 QSOs (Kozlowski, 2017)
J/A+A/622/A1 : LOFAR Two-metre Sky Survey DR1 source catalog (Shimwell+, 2019)
J/A+A/622/A4 : LOFAR observations XMM-LSS field (Hale+, 2019)
J/A+A/622/A8 : NGC 3184, 4736, 5055 and 5194 LOFAR & WSRT maps (Heesen+, 2019)
J/A+A/622/A11 : LoTSS/HETDEX. Optical quasars. I. (Guerkan+, 2019)
J/A+A/622/A13 : VLA double-double radio galaxy candidates images
(Mahatma+, 2019)
J/A+A/622/A15 : Broad absorption line quasars in LDR1 (Morabito+, 2019)
J/A+A/622/A22 : Abell 1914 multiwavelength radio images (Mandal+, 2019)
J/A+A/622/A23 : LoTSS HCG and MLCG systems (Nikiel-wroczynski+, 2019)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- SDSS SDSS name (HHMMSS.ss+DDMMSS.s)
20- 38 F19.15 mag iMAG SDSS i-band magnitude (z=2 k-corrected)
40- 61 A22 --- LOFAR Unique LOFAR name (ILTJHHMMSS.ss+DDMMSS.s) (1)
63- 84 E22.19 Jy F150 LOFAR 144 MHz flux density
86-106 E21.19 Jy e_F150 Error on LOFAR 144 MHz flux density
108-116 E9.6 Jy F100 ?=- Herschel 100micron flux density (2)
118-125 F8.6 Jy e_F100 ?=- Error on Herschel 100micron flux density
127-135 E9.6 Jy F160 ?=- Herschel 160micron flux density (2)
137-144 F8.6 Jy e_F160 ?=- Error on Herschel 160micron flux density
146-154 E9.6 Jy F250 ?=- Herschel 250micron flux density (2)
156-163 F8.6 Jy e_F250 ?=- Error on Herschel 250micron flux density
165-173 E9.6 Jy F350 ?=- Herschel 350micron flux density (2)
175-182 F8.6 Jy e_F350 ?=- Error on Herschel 350micron flux density
184-192 E9.6 Jy F500 ?=- Herschel 500micron flux density (2)
194-201 F8.6 Jy e_F500 ?=- Error on Herschel 500micron flux density
203-232 E30.26 --- RL Radio loudness parameter
234-239 F6.3 Msun BHmass ?=- Black hole mass (3)
241-262 E22.19 --- Eddratio ?=- Eddington ratio
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Note (1): Only quasars that match LOFAR sources in the LoTSS catalogue
(Shimwell et al., 2019, Cat. J/A+A/622/A1) have unique LOFAR names.
Note (2): Herschel measurements are only available over the HATLAS/NGP region.
Note (3): Black hole masses and Eddington ratio measurements provided
by Shen et al. (2011, Cat. J/ApJS/194/45) and
Kozlowski (2017, Cat. J/ApJS/228/9) were utilised.
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Acknowledgements:
Gulay Gurkan <gulay.gurkan.g(at)gmail.com>
References:
Shimwell et al., Paper I 2019A&A...622A...1S 2019A&A...622A...1S, Cat. J/A+A/622/A1
Williams et al., Paper II 2019A&A...622A...2W 2019A&A...622A...2W
Duncan et al., Paper III 2019A&A...622A...3D 2019A&A...622A...3D
Hale et al., Paper IV 2019A&A...622A...4H 2019A&A...622A...4H, Cat. J/A+A/622/A4
de Gasperin et al., Paper V 2019A&A...622A...5D 2019A&A...622A...5D
Arias et al., Paper VI 2019A&A...622A...6A 2019A&A...622A...6A
Emig et al., Paper VII 2019A&A...622A...7E 2019A&A...622A...7E
Heesen et al., Paper VIII 2019A&A...622A...8H 2019A&A...622A...8H, Cat, J/A+A/622/A8
Miskolczi et al., Paper IX 2019A&A...622A...9M 2019A&A...622A...9M
Croston et al., Paper X 2019A&A...622A..10C 2019A&A...622A..10C
Gurkan et al., Paper XI 2019A&A...622A..11G 2019A&A...622A..11G, Cat. J/A+A/622/A11
Hardcastle et al., Paper XII 2019A&A...622A..12H 2019A&A...622A..12H
Mahatma et al., Paper XIII 2019A&A...622A..13M 2019A&A...622A..13M, Cat. J/A+A/622/A13
Mooney et al., Paper XIV 2019A&A...622A..14M 2019A&A...622A..14M
Morabito et al., Paper XV 2019A&A...622A..15M 2019A&A...622A..15M, Cat. J/A+A/622/A15
O'Sullivan et al., Paper XVI 2019A&A...622A..16O 2019A&A...622A..16O
Sabater et al., Paper XVII 2019A&A...622A..17S 2019A&A...622A..17S
Stacey et al., Paper XVIII 2019A&A...622A..18S 2019A&A...622A..18S
Botteon et al., Paper XIX 2019A&A...622A..19B 2019A&A...622A..19B
Hoang et al., Paper XX 2019A&A...622A..20H 2019A&A...622A..20H
Hoang et al., Paper XXI 2019A&A...622A..21H 2019A&A...622A..21H
Mandal et al., Paper XXII 2019A&A...622A..22M 2019A&A...622A..22M, Cat. J/A+A/622/A22
Nikiel-Wroczynski et al., Paper XXIII 2019A&A...622A..23N 2019A&A...622A..23N
Savini et al., Paper XXIV 2019A&A...622A..24S 2019A&A...622A..24S
Wiber et al., Paper XXV 2019A&A...622A..25W 2019A&A...622A..25W
(End) Gulay Gurkan [CSIRO, Australia], Patricia Vannier [CDS] 16-Jan-2019