J/MNRAS/489/470 ALMA polarimetric follow-up of PACO sources (Galluzzi+, 2019)
ALMA Band 3 polarimetric follow-up of a complete sample of faint PACO sources.
Galluzzi V., Puglisi G., Burkutean S., Liuzzo E., Bonato M., Massardi M.,
Paladino R., Gregorini L., Ricci R., Trombetti T., Toffolatti L.,
Burigana C., Bonaldi A., Bonavera L., Casasola V., De Zotti G., Ekers R.D.,
di Serego Alighieri S., Lopez-Caniego M., Tucci M.
<Mon. Not. R. Astron. Soc., 489, 470-486 (2019)>
=2019MNRAS.489..470G 2019MNRAS.489..470G (SIMBAD/NED BibCode)
ADC_Keywords: Radio sources ; Spectra, millimetric/submm ; Polarization ;
Positional data
Keywords: galaxies: active - galaxies: statistics - radio continuum: galaxies
Abstract:
We present Atacama Large Millimetre/submillimiter Array (ALMA) high
sensitivity (σP∼0.4mJy) polarimetric observations at 97.5GHz
(Band 3) of a complete sample of 32 extragalactic radio sources drawn
from the faint Planck-ATCA Co-eval Observations (PACO) sample
(b←75°, compact sources brighter than 200mJy at 20GHz). We
achieved a detection rate of ∼97 per cent at 3σ (only 1
non-detection). We complement these observations with new Australia
Telescope Compact Array (ATCA) data between 2.1 and 35GHz obtained
within a few months and with data published in earlier papers from our
collaboration. Adding the co-eval GaLactic and Extragalactic All-sky
Murchison widefield array (GLEAM) survey detections between 70 and
230MHz for our sources, we present spectra over more than 3 decades in
frequency in total intensity and over about 1.7 decades in
polarization. The spectra of our sources are smooth over the whole
frequency range, with no sign of dust emission from the host galaxy at
mm wavelengths or of a sharp high frequency decline due, for example,
to electron ageing. We do however find indications of multiple
emitting components and present a classification based on the number
of detected components. We analyse the polarization fraction behaviour
and distributions up to 97GHz for different source classes. Source
counts in polarization are presented at 95GHz.
Description:
The observations were carried out with ALMA (Cycle 3, Project ID:
2015.1.01522.S, PI: Galluzzi) on 2016 August 24, and September 22th
and 27th, in four 2GHz-wide spectral bands centred at 90.5, 92.5,
102.5, and 104.5GHz, respectively, using 39 antennas in a compact
configuration (baseline range 118-1318m, corresponding to resolutions
of 4.8-0.3arcsec at 97.5GHz).
We observed a complete sample of 32 objects drawn from the faint PACO
sample (S20GHz>200mJy) in three circular regions at b←75° (each
with ∼10° diameter) that, altogether, contain ∼60 per cent of the
53 sources observed by Galluzzi et al. (2017MNRAS.465.4085G 2017MNRAS.465.4085G, Cat.
J/MNRAS/465/4085).
All the flux densities (total intensity and polarization), the
polarization angle, and the polarization fractions are reported in
Table 3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 117 32 ALMA Band 3 (central frequency: 97.5GHz)
observations performed at the end of August and
at the end of 2016 September
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See also:
J/MNRAS/465/4085 : PACO radio sources complete sample polarimetry
(Galluzzi+ 2017)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- ID [1/32] Sequential number of the source
4- 22 A19 --- Name AT20G source name (AT20GJHHMMSS+DDMMSS)
24- 42 A19 --- OName GLEAM counterpart name (GLEAMJHHMMSS+DDMMSS)
44- 52 F9.7 deg RAdeg Right ascension (J2000)
54- 64 F11.7 deg DEdeg Declination (J2000)
66- 67 A2 --- f_Name Flag on Name (1)
69- 75 F7.2 mJy I Flux density in total intensity (Stokes' I)
77- 81 F5.2 mJy e_I Error on I
83 A1 --- l_P Limit flag on P (2)
85- 89 F5.2 mJy P ? Linearly polarized flux density (3)
91- 94 F4.2 mJy e_P ? Error on P
96 A1 --- l_Pola Limit flag on Pola (2)
98-102 F5.2 % Pola ? Linear polarization fraction (4)
104-107 F4.2 % e_Pola ? Error on Pola
109-113 F5.1 deg Phi ? Polarization angle (5)
115-117 F3.1 deg e_Phi ? Error on Phipol
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Note (1): Flag as follows:
. = Point-like source
e = Extended source in this observation
pe = Probably extended source
Note (2): < marks a 3σ upper limit
Note (3): The linearly polarized emission, P, can be safely estimated from the
Stokes parameters Q and U only as: P=sqrt(Q2+U2)
Note (4): The polarization fraction is defined as Π=100xP/I
Note (5): The polarization angle is defined as Φ=1/2arctan(U/Q)
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 02-Jan-2023