J/A+A/656/A137 144MHz radio fluxes of z>5 quasars (Gloudemans+, 2021)
Low frequency radio properties of the z > 5 quasar population.
Gloudemans A.J., Duncan K.J., Rottgering H.J.A., Shimwell T.W.,
Venemans B.P., Best P.N., Bruggen M., Calistro Rivera G., Drabent A.,
Hardcastle M.J., Miley G.K., Schwarz D.J., Saxena A., Smith D.J.B.,
Williams W.L.
<Astron. Astrophys. 656, A137 (2021)>
=2021A&A...656A.137G 2021A&A...656A.137G (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Galaxies, radio
Keywords: quasars: general - galaxies: high-redshift - galaxies: active -
radio continuum: galaxies
Abstract:
Optically luminous quasars at z>5 are important probes of
super-massive black hole (SMBH) formation. With new and future radio
facilities, the discovery of the brightest low-frequency radio sources
in this epoch would be an important new probe of cosmic reionization
through 21-cm absorption experiments.
We present the result of a study of the low-frequency radio properties
of a sample of 115 known spectroscopically confirmed z>5 quasars using
the second data release of the Low Frequency Array (LOFAR) Two Meter
Sky survey (LoTSS-DR2), reaching noise levels of 80uJy/beam (at
144MHz) over an area of 5720 square degrees. We find that 41 sources
(36%) are detected in LoTSS-DR2 at >2σ significance and we
explore the evolution of their radio properties (power, spectral
index, and radio loudness) as a function of redshift and rest-frame
ultra-violet properties.
Description:
In this catalog we present the 144MHz flux and rest-frame UV
magnitude measurements of the z>5 quasars in LoTSS-DR2 from the sample
of Ross and Cross (2020MNRAS.494..789R 2020MNRAS.494..789R). The radio fluxes have been
measured using the known quasar positions and assuming the sources are
unresolved. We find a total of 41 tentative detections at >2σ
significance (including the 19 >5σ detected), where the errors
are based on the local RMS. For the full quasar sample we derived
rest-frame UV magnitudes by combining optical to mid-infrared
observations and perform spectral energy distribution fitting using
the template fitting code EAZY (Brammer et al., 2008ApJ...686.1503B 2008ApJ...686.1503B).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 108 488 Radio fluxes and rest-frame UV magnitudes of
z>5 quasars from Ross & Cross
(2020MNRAS.494..789R 2020MNRAS.494..789R) sample
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 F12.8 deg RAdeg Right ascension (J2000.0)
14- 26 F13.9 deg DEdeg Declination (J2000.0)
28- 31 F4.2 --- z Spectroscopic redshift
33- 38 F6.2 mJy F144MHz ?=-99 Total flux at 144MHz
40- 45 F6.2 mJy e_F144MHz ?=-99 Total flux at 144MHz error
47- 52 F6.2 mag B_M1450 ?=-99 Absolute magnitude at 1450Å
16th percentile
54- 59 F6.2 mag M1450 ?=-99 Absolute magnitude at 1450Å
50th percentile
61- 66 F6.2 mag b_M1450 ?=-99 Absolute magnitude at 1450Å
84th percentile
68- 73 F6.2 mag B_M2500 ?=-99 Absolute magnitude at 2500Å
16th percentile
75- 80 F6.2 mag M2500 ?=-99 Absolute magnitude at 2500Å
50th percentile
82- 87 F6.2 mag b_M2500 ?=-99 Absolute magnitude at 2500Å
84th percentile
89- 94 F6.2 mag B_M4400 ?=-99 Absolute magnitude at 4400Å
16th percentile
96-101 F6.2 mag M4400 ?=-99 Absolute magnitude at 4400Å
50th percentile
103-108 F6.2 mag b_M4400 ?=-99 Absolute magnitude at 4400Å
84th percentile
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Acknowledgements:
Anniek Gloudemans, gloudemans(at)strw.leidenuniv.nl
(End) Anniek Gloudemans [Leiden Univ.], Patricia Vannier [CDS] 16-Oct-2021