J/other/PASA/38.41 GLEAM 200MHz local radio luminosity function (Franzen+, 2021)
The GLEAM 200-MHz local radio luminosity function for AGN and star-forming
galaxies.
Franzen T.M.O., Seymour N., Sadler E.M., Mauch T., White S.V.,
Jackson C.A., Chhetri R., Quici B., Bell M.E., Callingham J.R.,
Dwarakanath K.S., For B., Gaensler B.M., Hancock P.J., Hindson L.,
Hurley-Walker N., Johnston-Hollitt M., Kapinska A.D., Lenc E.,
McKinley B., Morgan J., Offringa A.R., Procopio P., Staveley-Smith L.,
Wayth R.B., Wu C., Zheng Q.
<Publ. Astron. Soc. Australia, 38, 41 (2021)>
=2021PASA...38...41F 2021PASA...38...41F (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Galaxies, nearby ; Galaxies, radio ;
Radio continuum ; Radio sources
Keywords: radio continuum: galaxies - surveys - methods: data analysis -
catalogues - galaxies: active - galaxies: starburst
Abstract:
The GaLactic and Extragalactic All-sky Murchison Widefield Array
(GLEAM) is a radio continuum survey at 76-227MHz of the entire
southern sky (Declination <+30°) with an angular resolution of
∼2arcmin. In this paper, we combine GLEAM data with optical
spectroscopy from the 6dF Galaxy Survey to construct a sample of 1,590
local (median z∼0.064) radio sources with S200MHz>55mJy across
an area of ∼16700deg2. From the optical spectra, we identify the
dominant physical process responsible for the radio emission from each
galaxy: 73 per cent are fuelled by an active galactic nucleus (AGN)
and 27 per cent by star formation. We present the local radio
luminosity function for AGN and star-forming galaxies at 200MHz and
characterise the typical radio spectra of these two populations
between 76MHz and ∼1GHz. For the AGN, the median spectral index
between 200MHz and ∼1GHz, α, is -0.600±0.010 (where S
proportional to να) and the median spectral index within
the GLEAM band, αlow, is -0.704±0.011. For the star-forming
galaxies, the median value of αhigh is -0.650±0.010 and the
median value of αlow is -0.596±0.015. Among the AGN
population, flat-spectrum sources are more common at lower radio
luminosity, suggesting the existence of a significant population of
weak radio AGN that remain core-dominated even at low frequencies.
However, around 4 per cent of local radio AGN have ultra-steep radio
spectra at low frequencies (αlow←1.2). These
ultra-steep-spectrum sources span a wide range in radio luminosity,
and further work is needed to clarify their nature.
Description:
We have studied the local radio source population at 200MHz over most
of the southern sky (16679deg2) by combining the GLEAM Exgal and
SGP data with optical spectroscopy from the 6dFGS DR3. The GLEAM-6dFGS
sample contains 1590 sources with a median redshift of 0.064 and
200MHz radio luminosities in the range ∼1022-1027W/Hz. The optical
spectra indicate that 73 per cent of the sources are fuelled by AGN
activity and 27 per cent by star formation. The vast majority (81 per
cent) of the AGN have pure absorption-line spectra typical of giant
elliptical galaxies. The AGN with emission-line spectra typically have
lower luminosities and overlap in luminosity with the SF galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
6dfgsgl.dat 928 1590 6dFGS-GLEAM catalog
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See also:
VIII/100 : GaLactic and Extragalactic All-sky MWA survey (Hurley-Walker+, 2016)
VIII/102 : GLEAM II. Galactic plane (Hurley-Walker+, 2019)
VIII/109 : GLEAM III. South Galactic Pole (Franzen+, 2021)
VII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)
Byte-by-byte Description of file: 6dfgsgl.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- 6dFGS Target name of the object from the 6dFGS
data base, gHHMMSSs+DDMMSS
(6dFGStargetname)
17- 27 F11.7 deg RAdeg Right ascension of the object from the
2MASS XSC (J2000) (6dFGS_RAJ2000)
29- 39 F11.7 deg DEdeg Declination of the object from the
2MASS XSC (J2000) (6dFGS_DEJ2000)
41- 48 F8.6 --- z 6dFGS measured redshift (z)
50 I1 --- Q 6dFGS redshift quality flag (Q)
52- 57 F6.3 mag Kmag Total apparent K-band magnitude (K)
59- 66 F8.4 mag KMAG Total absolute K-band magnitude (K_abs)
68- 71 A4 --- SpClass Classification of the spectrum
(Spectrum_class)
73- 91 A19 --- AllWISE Name of the host galaxy in AllWISE,
JHHMMSS.ss+DDMMSS.s
(AllWISE_name)
93-103 F11.7 deg RAWdeg ?=- Right ascension of the host galaxy
(J2000) (AllWISE_RAJ2000)
105-115 F11.7 deg DEWdeg ?=- Declination of the host galaxy (J2000)
(AllWISE_DEJ2000)
117-122 F6.3 mag W1mag ?=- W1 magnitude of the host galaxy (W1mag)
124-128 F5.3 mag e_W1mag ?=- Error on W1 magnitude of the host
galaxy (err_W1mag)
130-135 F6.3 mag W2mag ?=- W2 magnitude of the host galaxy (W2mag)
137-141 F5.3 mag e_W2mag ?=- Error on W2 magnitude of the host
galaxy (err_W2mag)
143-148 F6.3 mag W3mag ?=- W3 magnitude of the host galaxy (W3mag)
150-154 F5.3 mag e_W3mag ?=- Error on W3 magnitude of the host
galaxy (err_W3mag)
156-161 F6.3 mag W4mag ?=- W4 magnitude of the host galaxy (W4mag)
163-167 F5.3 mag e_W4mag ?=- Error on W4 magnitude of the host
galaxy (err_W4mag)
169-188 A20 --- GLEAM Name of the GLEAM component (GLEAM_name),
GLEAM_JHHMMSSs-DDMMSS
190-200 F11.7 deg RAGdeg Right ascension of the GLEAM component
(J2000) (GLEAM_RAJ2000)
202-212 F11.7 deg DEGdeg Declination of the GLEAM component
(J2000) (GLEAM_DEJ2000)
214-223 F10.7 arcsec Offset Offset between GLEAM and 6dFGS positions
(Offset)
225-231 A7 --- Region Region of the GLEAM survey
(deep or shallow) (region)
233 I1 --- NGLEAM Number of GLEAM components (ncmp_GLEAM)
235-296 A62 --- GLEAMs Name(s) of any associated GLEAM
component(s) (GLEAMassociatedname)
298-299 I2 % eabsFpct Percentage error in absolute flux scale
(GLEAMerrabsfluxpct)
301-302 I2 % efitFpct Percentage error in internal flux scale
(GLEAMerrfitfluxpct)
304-315 F12.6 mJy S200 Integrated flux density at 200MHz
from GLEAM (S_200)
317-327 F11.6 mJy e_S200 Error on integrated flux density at 200MHz
from GLEAM (dS_200)
329-340 F12.6 mJy S076 Integrated flux density at 76MHz
from GLEAM (S_076)
342-352 F11.6 mJy e_S076 Error on integrated flux density at 76MHz
from GLEAM (dS_076)
354-365 F12.6 mJy S084 Integrated flux density at 84MHz
from GLEAM (S_084)
367-377 F11.6 mJy e_S084 Error on integrated flux density at 84MHz
from GLEAM (dS_084)
379-390 F12.6 mJy S092 Integrated flux density at 92MHz
from GLEAM (S_092)
392-401 F10.6 mJy e_S092 Error on integrated flux density at 92MHz
from GLEAM (dS_092)
403-414 F12.6 mJy S099 Integrated flux density at 99MHz
from GLEAM (S_099)
416-425 F10.6 mJy e_S099 Error on integrated flux density at 99MHz
from GLEAM (dS_099)
427-438 F12.6 mJy S107 Integrated flux density at 107MHz
from GLEAM (S_107)
440-449 F10.6 mJy e_S107 Error on integrated flux density at 107MHz
from GLEAM (dS_107)
451-462 F12.6 mJy S115 Integrated flux density at 115MHz
from GLEAM (S_115)
464-473 F10.6 mJy e_S115 Error on integrated flux density at 115MHz
from GLEAM (dS_115)
475-486 F12.6 mJy S122 Integrated flux density at 122MHz
from GLEAM (S_122)
488-497 F10.6 mJy e_S122 Error on integrated flux density at 122MHz
from GLEAM (dS_122)
499-510 F12.6 mJy S130 Integrated flux density at 130MHz
from GLEAM (S_130)
512-521 F10.6 mJy e_S130 Error on integrated flux density at 130MHz
from GLEAM (dS_130)
523-534 F12.6 mJy S143 Integrated flux density at 143MHz
from GLEAM (S_143)
536-545 F10.6 mJy e_S143 Error on integrated flux density at 143MHz
from GLEAM (dS_143)
547-558 F12.6 mJy S151 Integrated flux density at 151MHz
from GLEAM (S_151)
560-569 F10.6 mJy e_S151 Error on integrated flux density at 151MHz
from GLEAM (dS_151)
571-582 F12.6 mJy S158 Integrated flux density at 158MHz
from GLEAM (S_158)
584-593 F10.6 mJy e_S158 Error on integrated flux density at 158MHz
from GLEAM (dS_158)
595-606 F12.6 mJy S166 Integrated flux density at 166MHz
from GLEAM (S_166)
608-617 F10.6 mJy e_S166 Error on integrated flux density at 166MHz
from GLEAM (dS_166)
619-630 F12.6 mJy S174 Integrated flux density at 174MHz
from GLEAM (S_174)
632-641 F10.6 mJy e_S174 Error on integrated flux density at 174MHz
from GLEAM (dS_174)
643-654 F12.6 mJy S181 Integrated flux density at 181MHz
from GLEAM (S_181)
656-665 F10.6 mJy e_S181 Error on integrated flux density at 181MHz
from GLEAM (dS_181)
667-678 F12.6 mJy S189 Integrated flux density at 189MHz
from GLEAM (S_189)
680-689 F10.6 mJy e_S189 Error on integrated flux density at 189MHz
from GLEAM (dS_189)
691-702 F12.6 mJy S197 Integrated flux density at 197MHz
from GLEAM (S_197)
704-713 F10.6 mJy e_S197 Error on integrated flux density at 197MHz
from GLEAM (dS_197)
715-726 F12.6 mJy S204 Integrated flux density at 204MHz
from GLEAM (S_204)
728-737 F10.6 mJy e_S204 Error on integrated flux density at 204MHz
from GLEAM (dS_204)
739-750 F12.6 mJy S212 Integrated flux density at 212MHz
from GLEAM (S_212)
752-761 F10.6 mJy e_S212 Error on integrated flux density at 212MHz
from GLEAM (dS_212)
763-774 F12.6 mJy S220 ?=- Integrated flux density at 220MHz
from GLEAM (S_220)
776-785 F10.6 mJy e_S220 ?=- Error on integrated flux density at
220MHz from GLEAM (dS_220)
787-798 F12.6 mJy S227 ?=- Integrated flux density at 227MHz
from GLEAM (S_227)
800-809 F10.6 mJy e_S227 ?=- Error on integrated flux density at
227MHz from GLEAM (dS_227)
811-819 F9.6 --- alphaL ?=- Spectral index between 76 and 227MHz
from GLEAM (alpha_low)
821-828 F8.6 --- e_alphaL ?=- Error on spectral index between 76 and
227MHz from GLEAM (dalpha_low)
830-838 F9.6 --- rchi2alphaL ?=- Reduced chi squared value for GLEAM
spectral index fit
(reducedchi2alpha_low)
840 I1 --- refitFlag [0/1] "1" indicates that refitted GLEAM
measurements are used (refitted_flag)
842 I1 --- confFlag [0/1] "1" indicates severe source
confusion in GLEAM (confusion_flag)
844-850 F7.4 [W.Hz-1] P200 Logarithm of the radio luminosity at 200MHz
(P_200)
852-853 I2 --- NNVSS/SUMSS Number of NVSS/SUMSS components
(ncmp_NVSSorSUMSS)
855-865 F11.7 deg RAcdeg Right ascension of the centroid position
from NVSS/SUMSS (J2000)
(centroid_RAJ2000)
867-871 F5.2 arcsec e_RAcdeg Error on the RA of the centroid position
from NVSS/SUMSS (errcentroidRAJ2000)
873-883 F11.7 deg DEcdeg Declination of the centroid position from
NVSS/SUMSS (J2000) (centroid_DEJ2000)
885-889 F5.2 arcsec e_DEcdeg Error on the Dec of the centroid position
from NVSS/SUMSS (errcentroidDEJ2000)
891-896 F6.1 mJy SNVSS/SUMSS Integrated flux density at 1400/843MHz
from NVSS/SUMSS (S_NVSSorSUMSS)
898-902 F5.1 mJy e_SNVSS/SUMSS Error on integrated flux density at
1400/843MHz from NVSS/SUMSS
(dS_NVSSorSUMSS)
904-908 F5.2 --- alphaH Spectral index between 200 and 1400/843MHz
(alpha_high)
910-913 F4.2 --- e_alphaH Error on spectral index between 200 and
1400/843MHz (dalpha_high)
915-918 I4 MHz Freq Indicates whether NVSS or SUMSS is used
(Freq)
920-928 A9 --- G4Jy Name of the source from the G4Jy sample,
G4Jy NNNN (G4Jy_name)
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Acknowledgements:
Thomas Franzen, franzen(at)astron.nl
References:
Hurley-Walker et al., Paper I 2017MNRAS.464.1146H 2017MNRAS.464.1146H, Cat. VIII/100
Hurley-Walker et al., Paper II 2019PASA...36...47H 2019PASA...36...47H, Cat. VIII/102
Franzen et al., Paper III 2021PASA...38...14F 2021PASA...38...14F, Cat. VIII/109
(End) Patricia Vannier [CDS] 16-Aug-2021