J/ApJS/217/4 2FGL sources observed between 5-9GHz (Schinzel+, 2015)
New associations of gamma-ray sources from the Fermi Second Source Catalog.
Schinzel F.K., Petrov L., Taylor G.B., Mahony E.K., Edwards P.G.,
Kovalev YU.Y.
<Astrophys. J. Suppl. Ser., 217, 4 (2015)>
=2015ApJS..217....4S 2015ApJS..217....4S
ADC_Keywords: Gamma rays ; Radio continuum ; Active gal. nuclei ;
Supernova remnants
Keywords: catalogs; galaxies: active; gamma-rays: general;
radio continuum: general; surveys
Abstract:
We present the results of an all-sky radio survey between 5 and 9GHz
of sky areas surrounding all unassociated γ-ray objects listed
in the Fermi Large Area Telescope Second Source Catalog (2FGL). The
goal of these observations is to find all new γ-ray active
galactic nucleus (AGN) associations with radio sources >10mJy at 8GHz.
We observed with the Very Large Array and the Australia Telescope
Compact Array the areas around unassociated sources, providing
localizations of weak radio point sources found in 2FGL fields at
arcmin scales. Then we followed-up a subset of those with the Very
Long Baseline and the Long Baseline Arrays to confirm detections of
radio emission on parsec-scales. We quantified association
probabilities based on known statistics of source counts and assuming
a uniform distribution of background sources. In total we found 865
radio sources at arcsec scales as candidates for association and
detected 95 of 170 selected for follow-up observations at
milliarcsecond resolution. Based on this we obtained firm associations
for 76 previously unknown γ-ray AGNs. Comparison of these new
AGN associations with the predictions from using the Wide-field
Infrared Survey Explorer color-color diagram shows that half of the
associations are missed. We found that 129 out of 588 observed
γ-ray sources at arcmin scales not a single radio continuum
source was detected above our sensitivity limit within the 3σ
γ-ray localization. These "empty" fields were found to be
particularly concentrated at low Galactic latitudes. The nature of
these Galactic γ-ray emitters is not yet determined.
Description:
A list of 216 target fields were observed with the Very Large Array
(VLA). The instantaneous bandwidth was split into two parts, with one
half centered at 5.0GHz (4.5-5.5GHz) and the other centered at 7.3GHz
(6.8-7.8GHz); on 2012 October 26 and 2012 November 3. See section 2.1
During the first campaign with the Australia Telescope Compact Array
(ATCA), from 2012 September 19-20, we observed 411 2FGL unassociated
sources in a decl. range of [-90°, +10°] at 5.5 and 9GHz. The
details of that observing campaign and results have been reported by
Petrov et al. (2013, J/MNRAS/432/1294). We detected a total of 424
point sources. In a second ATCA campaign on 2013 September 25-28, we
re-observed sources that were detected at 5GHz, but were not detected
at 9GHz. See section 2.2.
Follow-up observations of 149 targets selected from the VLA and ATCA
survey above -30° decl. were conducted with the Very Long Baseline
Array (VLBA) between 2013 Feb-Aug (VCS7 project; 4.128-4.608 and
7.392-7.872GHz simultaneously) and in 2013 Jun-Dec (campaign S5272;
7.392-7.872GHz only). See section 2.3.
For sources with decl. below -30° we added 21 objects to the
on-going LCS campaign (Petrov et al. 2011, J/MNRAS/414/2528) in 2013
Mar-2013 Jun at 8.200-8.520GHz. See section 2.4.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 152 148 The 148 objects that were detected at 5.0/5.5 and/or
7.3/9.0GHz within 2.7' of the 137 2FGL counterpart
localization
table3.dat 152 501 The 501 objects that were detected at 5.0/5.5 and/or
7.3/9.0GHz between 2.7' and 6.5' of
the 324 2FGL counterpart localization
table4.dat 99 216 The 216 objects that were detected outside of the
6.5 arcmin and were within the 99% position
uncertainty of the 118 2FGL counterpart localization
table5.dat 97 1025 Possible counterparts from previous radio source
catalogs, the ALLWISE catalog, and the Supercosmos
database for radio sources found in category I
(table2), II (table3), and III (table4)
table6.dat 68 117 The 117 2FGL fields for which no radio point source
was detected within the 4σ localization
error at both 5.0/5.5 and 7.3/9.0GHz
table7.dat 77 95 The 95 VLBI detected radio sources in the fields of
90 2FGL unassociated γ-ray objects
table8.dat 55 167 The 167 possible associations of 112 2FGL
unassociated sources from literature
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See also:
II/328 : AllWISE Data Release (Cutri+ 2013)
VII/253 : A Catalogue of Galactic Supernova Remnants (Green, 2009)
VIII/81 : Sydney University Molonglo Sky Survey (SUMSS V2.1) (Mauch+ 2008)
VIII/82 : 2nd Epoch Molonglo Galactic Plane Survey (MGPS-2) (Murphy+, 2007)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
J/ApJS/217/2 : Refined associations of Fermi/LAT sources (Massaro+, 2015)
J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)
J/ApJS/209/34 : The first Fermi-LAT >10GeV catalog (1FHL) (Ackermann+, 2013)
J/AJ/146/5 : Optically Bright extragalactic Radio Sources II (Petrov+, 2013)
J/MNRAS/432/1294 : Fermi unassociated sources ATCA observations (Petrov+, 2013)
J/ApJS/206/13 : Blazars with γ-ray counterparts. II. (Massaro+, 2013)
J/ApJS/199/31 : Fermi LAT second source catalog (2FGL) (Nolan+, 2012)
J/MNRAS/419/1097 : The EVN Galactic Plane Survey - EGaPS (Petrov, 2012)
J/ApJ/744/177 : VLBA 5GHz observations of Fermi/LAT AGNs (Linford+, 2012)
J/ApJ/743/171 : The 2LAC catalog (Ackermann+, 2011)
J/AJ/142/105 : Optically Bright Extragalactic Radio Sources (Petrov+, 2011)
J/AJ/142/89 : Precise astrometry with VLBA (VIPS) (Petrov+, 2011)
J/AJ/142/35 : The VLBA Galactic Plane Survey (VGaPS) (Petrov+, 2011)
J/MNRAS/414/2528 : LBA Calibrator Survey (LCS1) (Petrov+, 2011)
J/ApJS/188/405 : Fermi-LAT first source catalog (1FGL) (Abdo+, 2010)
J/ApJ/707/L56 : VLBI and bright Fermi/LAT sources (Kovalev, 2009)
J/ApJS/183/46 : Fermi/LAT bright gamma-ray source list (0FGL) (Abdo+, 2009)
J/A+A/489/849 : Revised catalog of EGRET gamma-ray sources (Casandjian+, 2008)
J/AJ/136/580 : Sixth VLBA calibrator survey: VCS6 (Petrov+, 2008)
J/ApJS/174/481 : 2LC Compact Radio Sources in the GC (Lazio+, 2008)
J/ApJ/671/1355 : EGRET blazars in VIPS (Taylor+, 2007)
J/AJ/133/1236 : Fifth VLBA calibrator survey: VCS5 (Kovalev+, 2007)
J/ApJ/649/759 : Bubbles in the galactic disk (Churchwell+, 2006)
J/AJ/131/1872 : Fourth VLBA calibrator survey: VCS4 (Petrov+, 2006)
J/AJ/129/1993 : ATNF Pulsar Catalog (Manchester+, 2005)
J/AJ/129/1163 : Third VLBA calibrator survey: VCS3 (Petrov+, 2005)
J/AJ/129/348 : Radio compact HII regions in the Milky Way (Giveon+, 2005)
J/AJ/126/2562 : Second VLBA calibrator survey: VCS2 (Fomalont+, 2003)
J/A+A/397/213 : Galactic HII regions (Paladini+, 2003)
J/ApJS/141/13 : VLBA calibrator survey: VCS1 catalog (Beasley+, 2002)
J/A+AS/131/11 : Radio sources related to gamma-ray emission (Reich+ 1998)
J/A+AS/126/413 : 21cm radio continuum survey. II. (Reich+ 1997)
J/A+AS/85/805 : 11cm radio continuum survey. IV. (Fuerst+ 1990)
http://astrogeo.org/rfc/ : Radio Fundamental Catalog home page
Byte-by-byte Description of file: table[23].dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name IAU name of the radio source (JHHMM+DDMM)
12- 24 A13 --- 2FGL 2FGL name of γ-ray source (JHHMM.m+DDMMc)
26- 27 A2 --- fr Flag on radio source (G1)
29- 30 I2 h RAh Hour of Right Ascension (J2000)
32- 33 I2 min RAm Minute of Right Ascension (J2000)
35- 39 F5.2 s RAs Second of Right Ascension (J2000)
41 A1 --- DE- Sign of the Declination (J2000)
42- 43 I2 deg DEd Degree of Declination (J2000)
45- 46 I2 arcmin DEm Arcminute of Declination (J2000)
48- 52 F5.2 arcsec DEs Arcsecond of Declination (J2000)
54- 58 F5.2 arcsec e_RAs [0/57] Uncertainty in RAs;
without cosδ factor
60- 64 F5.2 arcsec e_DEs [0.01/59] Uncertainty in DEs
66- 72 F7.2 mJy F5 ?=-9.9 Flux density at 5GHz
74- 79 F6.2 mJy F7 ?=-9.9 Flux density at 7GHz
81- 87 F7.2 mJy F9 [1/9196]?=-9.9 Flux density at 9GHz
89- 93 F5.2 mJy e_F5 ?=-9.9 Uncertainty in F5
95- 99 F5.2 mJy e_F7 ?=-9.9 Uncertainty in F7
101-105 F5.2 mJy e_F9 [0.1/6.2]?=-9.9 Uncertainty in F9
107-111 F5.2 --- Sp5 ?=-9.9 Spectral index between 4.58 and 6.42GHz
113-117 F5.2 --- Sp9 [-5.8/7.4]?=-9.9 Spectral index between
4.58 and 6.42GHz
119-123 F5.2 --- e_Sp5 ?=-9.9 Error in Sp5
125-129 F5.2 --- e_Sp9 [0.01/4.1]?=-9.9 Error in Sp9
131-135 F5.2 --- Sp ?=-9.9 Spectral index between 5 and 9/7GHz
137-141 F5.2 --- e_Sp ?=-9.9 Uncertainty in Sp
143-145 F3.1 arcmin Sep [0/6.5] Distance between γ-ray and
radio source
147-149 F3.1 --- Nd [0/3] Distance between γ-ray and radio
source; normalized by its uncertainty
151-152 A2 --- Camp Campaign (V1:VLA, A1/A2: ATCA)
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name IAU name of the radio source (JHHMM+DDMM)
12- 24 A13 --- 2FGL 2FGL name of γ-ray source (JHHMM.m+DDMMc)
26- 27 A2 --- fr Flag on radio source (G1)
29- 30 I2 h RAh Hour of Right Ascension (J2000)
32- 33 I2 min RAm Minute of Right Ascension (J2000)
35- 39 F5.2 s RAs Second of Right Ascension (J2000)
41 A1 --- DE- Sign of the Declination (J2000)
42- 43 I2 deg DEd Degree of Declination (J2000)
45- 46 I2 arcmin DEm Arcminute of Declination (J2000)
48- 52 F5.2 arcsec DEs Arcsecond of Declination (J2000)
54- 58 F5.2 arcsec e_RAs [0.01/57] Uncertainty in RAs;
without cosδ factor
60- 64 F5.2 arcsec e_DEs [0.01/16.1] Uncertainty in DEs
66- 72 F7.2 mJy F5 ?=-9.9 Flux density at 5GHz
74- 79 F6.2 mJy F7 ?=-9.9 Flux density at 7GHz
81- 87 F7.2 mJy F9 [0.7/1589.1]?=-9.9 Flux density at 9GHz
89- 92 F4.1 arcmin Sep [6.5/19.4] Distance between γ-ray
and radio source
94- 96 F3.1 --- Nd [0/3] Distance between γ-ray and radio
source; normalized by its uncertainty
98- 99 A2 --- Camp Campaign (V1:VLA, A1/A2: ATCA)
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Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name IAU name of the radio source (JHHMM+DDMM)
12- 18 F7.1 mJy F1 ?=-9.9 Flux density of matching source at 1GHz (1)
20- 33 A14 --- ID1 ID of matching object in 1GHz catalog
(JHHMMSS+DDMMSS) (1)
35- 36 A2 --- C1 Matching 1GHz catalog label (2)
38- 56 A19 --- WISE ID of a matching object in WISE catalog
(JHHMMSS.ss+DDMMSS.s)
58- 61 F4.1 arcsec Dopt [0/3.5]?=-9.9 Distance between optical & radio
localization
63- 64 I2 h RAh ? Hour of Right Ascension (J2000) (3)
66- 67 I2 min RAm ? Minute of Right Ascension (J2000) (3)
69- 73 F5.2 s RAs ? Second of Right Ascension (J2000) (3)
75 A1 --- DE- ? Sign of the Declination (J2000) (3)
76- 77 I2 deg DEd ? Degree of Declination (J2000) (3)
79- 80 I2 arcmin DEm ? Arcminute of Declination (J2000) (3)
82- 85 F4.1 arcsec DEs ? Arcsecond of Declination (J2000) (3)
87- 90 F4.1 mag Bmag [10/23]?=-9.9 Optical B magnitude
92- 95 F4.1 mag Rmag [13/21.5]?=-9.9 Optical R magnitude
97 I1 --- Copt [1/2]? Optical classification (1=extended or
2=stellar or point like object)
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Note (1): From NVSS (1.4GHz; Cat. VIII/65), SUMSS (0.843GHz; Cat. VIII/70), or
MGPS-2 (0.843GHz; Cat. VIII/82, in Simbad)
catalogs.
Note (2): Two letter combinations with N indicating matching entries found
in multiple catalogs, e.g. NM = source found in NVSS and MGPS-2:
N=NVSS, M=MGPS-2, S=SUMSS
Note (3): Of optical counterpart in the Supercosmos database
(Hambly et al. 2001MNRAS.326.1279H 2001MNRAS.326.1279H).
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- 2FGL 2FGL name of γ-ray source (JHHMM.m+DDMMc)
16- 17 I2 h RAh Hour of Right Ascension (J2000)
19- 20 I2 min RAm Minute of Right Ascension (J2000)
22- 23 I2 s RAs Second of Right Ascension (J2000)
25 A1 --- DE- Sign of the Declination (J2000)
26- 27 I2 deg DEd Degree of Declination (J2000)
29- 30 I2 arcmin DEm Arcminute of Declination (J2000)
32- 33 I2 arcsec DEs Arcsecond of Declination (J2000)
35- 42 F8.4 deg GLON Galactic Longitude
44- 51 F8.4 deg GLAT Galactic Latitude
53- 59 F7.4 --- rms5 [0.009/12] The 5GHz image rms noise; mJy/beam
61- 65 F5.3 --- rms7 [0.01/4.2] The 7/9GHz image rms noise;
in mJy/beam
67- 68 A2 --- fr Flag on radio source (G1)
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Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name IAU name of the radio source (JHHMM+DDMM)
13- 24 A12 --- 2FGL 2FGL name of γ-ray source (JHHMM.m+DDMM)
26- 27 I2 h RAh Hour of Right Ascension (J2000)
29- 30 I2 min RAm Minute of Right Ascension (J2000)
32- 38 F7.4 s RAs Second of Right Ascension (J2000)
40 A1 --- DE- Sign of the Declination (J2000)
41- 42 I2 deg DEd Degree of Declination (J2000)
44- 45 I2 arcmin DEm Arcminute of Declination (J2000)
47- 53 F7.4 arcsec DEs Arcsecond of Declination (J2000)
55- 59 F5.3 Jy S [0.005/0.4] VLBI flux density
61- 64 F4.2 arcsec Sep [0.2/9.7] Distance between γ-ray and
radio positions
66- 69 F4.2 --- Nd [0/3.4] Distance between γ-ray and radio
source; normalized by its uncertainty
71- 77 F7.1 --- Lambda [0.3/16462] Likelihood ratio Λ
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Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- 2FGL 2FGL name of γ-ray source (JHHMM.m+DDMMc)
15- 29 A15 --- Assoc Name of associated source
31- 33 A3 --- Type Source type (1)
34 A1 --- u_Type [?] '?' if not confirmed
37- 55 A19 --- BibCode ADS bibcode reference
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Note (1): Type as follows:
SNR = Supernova Remnant (134 sources);
PSR = Pulsar (28 sources);
XSS = X-ray Binary Star System (2 sources);
BSS = Binary Star System (1 source);
AGN = Active Galactic Nucleus (1 source).
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Global notes:
Note (G1): Flag as follows:
e = a source was found in a field of extended objects;
f = a source has spectral index flatter than -0.5 between 5 and 7/9GHz.
* = a point source outside of the 3σ γ-ray localization
was found.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Apr-2015