J/ApJS/189/1 A 3.5mm polarimetric survey of radio-loud AGNs (Agudo+, 2010)
A 3.5 mm polarimetric survey of radio-loud active galactic nuclei.
Agudo I., Thum C., Wiesemeyer H., Krichbaum T.P.
<Astrophys. J. Suppl. Ser., 189, 1-14 (2010)>
=2010ApJS..189....1A 2010ApJS..189....1A
ADC_Keywords: BL Lac objects ; Active gal. nuclei ; QSOs ; Polarization
Surveys ; Radio sources ; Redshifts ; Magnitudes
Keywords: BL Lacertae objects: general - galaxies: active - galaxies: jets -
polarization - quasars: general - surveys
Abstract:
We present the results from the first large (>100 sources) 3.5mm
polarimetric survey of radio-loud active galactic nuclei (AGNs). This
wavelength is favorable within the radio-millimeter range for
measuring the intrinsic linearly polarized emission from AGNs, since
in general it is only marginally affected by Faraday rotation of the
electric vector position angle and depolarization. The I, Q, U, and V
Stokes parameter observations were performed with the XPOL polarimeter
at the IRAM 30m Telescope on different observing epochs from 2005 July
(when most of the measurements were made) to 2009 October. Our sample
consists of 145 flat-radio-spectrum AGNs with declination >-30°
(J2000.0) and flux density ≳1Jy at ∼86GHz, as measured at the IRAM
30m Telescope from 1978 to 1994. This constraint on the radio spectrum
causes our sample to be dominated by blazars, which allows us to
conduct new statistical studies on this class of high-luminosity,
relativistically beamed emitters. Over our entire source sample, the
luminosity of the jets is anticorrelated with the degree of linear
polarization. Consistent with previous findings claiming larger
Doppler factors for brighter γ-ray blazars, quasars listed in
our sample, and in the Fermi Large Area Telescope Bright Source
Catalog (LBAS, Abdo et al., 2009ApJ...700..597A 2009ApJ...700..597A), show larger
luminosities than non-LBAS ones, but our data do not allow us to
confirm the same for BL Lac objects. Our new data can be used to
estimate the 3.5mm AGN contribution to measurements of the linear
polarization of the cosmic microwave background, such as those
performed by the Planck satellite.
Description:
In Table 1, we present our sample of 145 observed sources (see also
Fig. 1) which has been built essentially from the 138 radio-loud AGNs
in the IRAM pointing sources that were contained in the 1Jy catalog
(Kuhr et al. 1981, Cat. VIII/5) and/or in the catalog of 404 compact
radio sources by Perley (1982, Cat. J/AJ/87/859).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 79 145 Source properties
table2.dat 68 145 Summary of observing results
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See also:
B/iram : Plateau de Bure Interferometer Observation Log (IRAM 1991-2010)
VIII/5 : Bright Extragalactic Radio Sources (1Jy) (Kuehr+, 1981)
VIII/66 : IRAM observations in pre-star forming regions (Falgarone+ 1998-2001)
VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)
J/AJ/87/859 : Polarisation of 404 radio sources at 6 and 20cm (Perley, 1982)
J/ApJS/99/297 : First Caltech-Jodrell Bank VLBI Survey. III (Xu+ 1995)
J/ApJS/131/95 : VSOP 5 GHz continuum survey (Fomalont+, 2000)
J/ApJ/609/539 : Kinematics of parsec-scale radio jets (Kellermann+, 2004)
J/AJ/130/1418 : AGN jet kinematics (Jorstad+, 2005)
J/AJ/130/1389 : Linear polarization of AGN jets at 15GHz (Lister+, 2005)
J/ApJ/626/95 : Gamma-ray blazar candidates (Sowards-Emmerd+, 2005)
J/ApJS/183/46 : Fermi/LAT bright gamma-ray source list (0FGL) (Abdo+, 2009)
J/A+A/476/L17 : 86 and 43GHz observations of NRAO 150 (Agudo+, 2007)
J/A+A/484/119 : Multi-epoch VLBI survey of CJF sources (Britzen+, 2008)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name IAU B1950.0 source name (HHMM+DDd) (1)
10 A1 --- f_Name [a] Quasar missing in [VV2006] (2)
12- 20 A9 --- OName Common source name
22- 23 I2 h RAh Hour of Right Ascension (J2000)
25- 26 I2 min RAm Minute of Right Ascension (J2000)
28- 34 F7.4 s RAs Second of Right Ascension (J2000)
36 A1 --- DE- Sign of the Declination (J2000)
37- 38 I2 deg DEd Degree of Declination (J2000)
40- 41 I2 arcmin DEm Arcminute of Declination (J2000)
43- 48 F6.3 arcsec DEs Arcsecond of Declination (J2000)
50- 54 F5.3 --- z ? Redshift from Veron et al. (2006, Cat. VII/248)
56 A1 --- r_z Origin of z (3)
58 A1 --- cl [BGQU] Optical classification from Veron et al.
(2006, Cat. VII/248; see also Cat. VII/258)
(BL Lac, Galaxy, Quasar or Unknown)
60 A1 --- r_cl Origin of class (4)
62- 65 F4.1 mag Vmag ? Veron et al. (2006, Cat. VII/248) V band
magnitude (may not be V, see f_Vmag)
67 A1 --- f_Vmag [ce ] Vmag refers to R- or optical band (5)
69- 71 I3 deg phi ? Jet position angle
73- 74 I2 GHz nu ? Observing frequency from which phi was obtained
76- 77 I2 --- r_phi ? References for phi (6)
79 A1 --- g? [Y ] Source in the γ-ray Fermi Large Area
Telescope Bright Source catalog (LBAD, Abdo et
al. 2009ApJ...700..597A 2009ApJ...700..597A, see Cat. J/ApJS/183/46)
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Note (1): in Simbad.
Note (2): 'a' designates QSO not present in Veron-Cetty & Veron
(2006, Cat. VII/248, obsoleted by Cat. VII/258) catalog.
<[VV2006] JHHMMSS.s+DDMMSSa> for QSOs,
<[VV2006b] JHHMMSS.s+DDMMSSa> for BL Lac and
<[VV2006c] JHHMMSS.s+DDMMSSa> for AGNs objects in Simbad.
Note (3): Redshift notes as follows:
b = Redshift from Sowards-Emmerd et al. (2005, Cat. J/ApJ/626/95);
f = From Agudo et al. (2007, Cat. J/A+A/476/L17) and Acosta-Pulido et al.
(2010, in press (1003.3542));
g = Redshift from Wills & Wills (1976ApJS...31..143W 1976ApJS...31..143W);
h = Redshift from Nilsson et al. (2008A&A...487L..29N 2008A&A...487L..29N);
j = z=0.245 from Britzen et al. (2008, Cat. J/A+A/484/119). Sbarufatti et al.
(2005ApJ...635..173S 2005ApJ...635..173S) give z>0.75.
l = Redshift from Lawrence et al. (1986AJ.....91..494L 1986AJ.....91..494L).
Note (4): Object type notes as follows:
d = Classified as a possible galaxy in Veron et al. (2006, VII/248, obsoleted
by VII/258) catalog;
i = Classified as a galaxy in Veron-Cetty & Veron (2006, VII/248) catalog;
k = Classified as a quasar in Veron-Cetty & Veron (2006, VII/248) catalog;
m = Classified as a BL Lac in Veron-Cetty & Veron (2006, VII/248) catalog.
Note (5): V magnitude notes as follows:
c = In column Vmag, Rmag from NED.
e = In column Vmag, optical mag from NED.
Note (6): References for phi as follows:
1 = Agudo et al. (2007, Cat. J/A+A/476/L17);
2 = BU- Blazar Group Web site (http://www.bu.edu/blazars);
3 = Fomalont et al. (2000, Cat. J/ApJS/131/95);
4 = Jorstad et al. (2005, Cat. J/AJ/130/1418);
5 = Kellermann et al. (2004, Cat. J/ApJ/609/539);
6 = Lee et al. (2008AJ....136..159L 2008AJ....136..159L);
7 = Lister et al. (2009ApJ...696L..22L 2009ApJ...696L..22L);
8 = Lister & Homan (2005, Cat. J/AJ/130/1389);
9 = MOJAVE Web site (http://www.physics.purdue.edu/mojave/);
10 = USNO Radio Reference Frame Image Database Web site
(http://rorf.usno.navy.mil/rrfid.shtml);
11 = Xu et al. (1995, Cat. J/ApJS/99/297).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name IAU B1950.0 source name (HHMM+DDd)
10- 13 A4 month Month Month of observations
15- 18 I4 yr Year Year of observations
20- 23 F4.1 s Int Integration time
25- 29 F5.2 Jy S86.2 86.2GHz flux density
31- 34 F4.2 Jy e_S86.2 Uncertainty in S86.2
36 A1 --- l_mL Upper limit flag in mL
37- 41 F5.2 % mL ? Fractional linear polarization
43- 46 F4.2 % e_mL ? Uncertainty in mL
48- 52 F5.1 deg chi ? Linear polarization electric vector
position angle
54- 56 F3.1 deg e_chi ? Uncertainty in chi
58 A1 --- l_mC Upper limit flag in mC
59- 63 F5.2 % mC ? Fractional circular polarization
65- 68 F4.2 % e_mC ? Uncertainty in mC
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 06-Sep-2010