J/ApJS/217/2 Refined associations of Fermi/LAT sources (Massaro+, 2015)
Refining the associations of the Fermi Large Area Telescope source catalogs.
Massaro F., D'Abrusco R., Landoni M., Paggi A., Masetti N., Giroletti M.,
Oti-Floranes H., Chavushyan V., Jimenez-Bailon E., Patino-Alvarez V.,
Digel S.W., Smith H.A., Tosti G.
<Astrophys. J. Suppl. Ser., 217, 2 (2015)>
=2015ApJS..217....2M 2015ApJS..217....2M
ADC_Keywords: Gamma rays ; Cross identifications ; Surveys ; Redshifts ;
Active gal. nuclei
Keywords: galaxies: active; methods: statistical; quasars: general; surveys
Abstract:
The Fermi-Large Area Telescope (LAT) First Source Catalog (1FGL) was
released in 2010 February and the Fermi-LAT 2-Year Source Catalog
(2FGL) appeared in 2012 April, based on data from 24 months of
operation. Since they were released, many follow up observations of
unidentified γ-ray sources have been performed and new
procedures for associating γ-ray sources with potential
counterparts at other wavelengths have been developed. Here we review
and characterize all of the associations as published in the 1FGL and
2FGL catalogs on the basis of multifrequency archival observations. In
particular, we located 177 spectra for the low-energy counterparts
that were not listed in the previous Fermi catalogs, and in addition
we present new spectroscopic observations of eight γ-ray blazar
candidates. Based on our investigations, we introduce a new
counterpart category of "candidate associations" and propose a refined
classification for the candidate low-energy counterparts of the Fermi
sources. We compare the 1FGL-assigned counterparts with those listed
in 2FGL to determine which unassociated sources became associated in
later releases of the Fermi catalogs. We also search for potential
counterparts to all of the remaining unassociated Fermi sources.
Finally, we prepare a refined and merged list of all of the
associations of 1FGL plus 2FGL that includes 2219 unique Fermi
objects. This is the most comprehensive and systematic study of all
the associations collected for the γ-ray sources available to
date. We conclude that 80% of the Fermi sources have at least one
known plausible γ-ray emitter within their positional
uncertainty regions.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 476 2219 Refined associations of the Fermi catalogs
refs.dat 119 40 References
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See also:
VIII/97 : 74MHz VLA Low-frequency Sky Survey Redux (VLSSr) (Lane+, 2014)
IX/43 : 1SXPS Swift X-ray telescope point source catalogue (Evans+ 2014)
VII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)
VIII/69 : The WISH catalogue at 352 MHz (de Breuck+ 2002)
J/ApJS/213/3 : Low-frequency flat spectrum sources (LORCAT) (Massaro+, 2014)
J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)
J/AJ/147/143 : MOJAVE. XI. Spectral distributions (Hovatta+, 2014)
J/ApJS/209/34 : The first Fermi-LAT >10GeV catalog (1FHL) (Ackermann+, 2013)
J/ApJS/209/10 : UGSs. V. kernel approach (Massaro+, 2013)
J/ApJS/209/9 : Unidentified gamma-ray sources. IV. X-ray (Paggi+, 2013)
J/ApJS/208/25 : Swift X-ray observations of 1FGL sources (Takeuchi+, 2013)
J/ApJS/208/17 : 2nd Fermi LAT cat. of gamma-ray pulsars (2PC) (Abdo+, 2013)
J/ApJS/207/4 : Unidentified γ sources. III. Radio (Massaro+, 2013)
J/AJ/146/10 : Spectro. of emission-line ICRF2 candidates (Titov+, 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/206/12 : Blazars with γ-ray counterparts. I. (D'Abrusco+, 2013)
J/ApJ/771/57 : Fermi-LAT flaring gamma sources from FAVA (Ackermann+, 2013)
J/ApJ/764/135 : Spectroscopic redshifts of BL Lac objects (Shaw+, 2013)
J/MNRAS/428/220 : Gamma-ray AGN type determination (Hassan+, 2013)
J/A+A/548/A99 : XMM-Newton Slew Survey in 2-10keV (Warwick+, 2012)
J/AJ/144/105 : MOJAVE. VIII. Faraday rotation in AGN jets. (Hovatta+, 2012)
J/ApJ/756/33 : X-ray sources near 2 bright γ sources (Cheung+, 2012)
J/MNRAS/424/L64 : AGN/pulsar distinction for 2FGL sources (Mirabal+, 2012)
J/ApJ/753/83 : Associations to 1FGL sources (Ackermann+, 2012)
J/ApJ/752/61 : Blazars in unidentified γ-ray sources (Massaro+, 2012)
J/A+A/541/A160 : Planck + X/γ observations of blazars (Giommi+, 2012)
J/ApJS/199/31 : Fermi LAT second source catalog (2FGL) (Nolan+, 2012)
J/ApJ/748/68 : WISE IR colors of gamma-ray blazars (D'Abrusco+, 2012)
J/other/NewA/16.503 : 2MASS observation of BL Lac objects II. (Mao+, 2011)
J/ApJ/743/171 : The 2LAC catalog (Ackermann+, 2011)
J/ApJ/742/66 : New Fermi/LAT extragalactic sources (Teng+, 2011)
J/ApJ/742/27 : 15GHz and jet properties of MOJAVE blazars (Lister+, 2011)
J/ApJ/741/30 : Radio/γ-ray correlation in AGN (Ackermann+, 2011)
J/ApJS/195/8 : The QUaD Galactic Plane Survey. II. (Culverhouse+, 2011)
J/A+A/520/A47 : Blazars in the Swift-BAT hard X-ray sky (Maselli+, 2010)
J/ApJ/718/587 : The Fermi-AT20G catalog (Mahony+, 2010)
J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)
J/ApJS/188/405 : Fermi-LAT first source catalog (1FGL) (Abdo+, 2010)
J/ApJ/715/429 : First Fermi-LAT AGN catalog (1LAC) (Abdo+, 2010)
J/MNRAS/402/2403 : Australia Telescope 20GHz Survey Catalog (Murphy+, 2010)
J/ApJ/707/L56 : VLBI and bright Fermi/LAT sources (Kovalev, 2009)
J/ApJ/706/L7 : The Fermi LAT sky as seen by INTEGRAL/IBIS (Ubertini+, 2009)
J/A+A/495/691 : Multifrequency blazars catalog, Roma-BZCAT (Massaro+, 2009)
J/ApJS/175/97 : CGRaBS: survey of γ-ray blazar cand. (Healey+, 2008)
J/ApJ/671/1355 : EGRET blazars in VIPS (Taylor+, 2007)
J/A+A/476/759 : X-ray properties of AGN from the CJF sample (Britzen+, 2007)
J/ApJS/171/61 : Survey of Flat-Spectrum Radio Sources (Healey+, 2007)
J/ApJS/135/155 : Radio identification of 3EG EGRET sources (Mattox+, 2001)
J/MNRAS/323/757 : Deep X-Ray Radio Blazar Survey (DXRBS). II. (Landt+, 2001)
J/ApJS/129/547 : RBSC-NVSS sample. I. (Bauer+, 2000)
J/ApJ/481/95 : Radio identification of EGRET sources (Mattox+ 1997)
J/ApJS/107/239 : 327MHz survey of the galactic plane (Taylor+ 1996)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [1FGL]
6- 18 A13 --- 1FGL 1FGL name (JHHMM.m+DDMM)
20- 23 A4 --- --- [2FGL]
25- 37 A13 --- 2FGL 2FGL name (JHHMM.m+DDMM)
39- 42 A4 --- --- [1FHL]
44- 56 A13 --- 1FHL 1FHL name (JHHMM.m+DDMM)
58 A1 --- gcl gamma-ray source category (1)
60-103 A44 --- C1 The first low-energy counterpart
105-190 A86 --- n_C1 Multifrequency notes for C1 (2)
192-198 F7.5 --- z [0/3.2]? Redshift estimate
200-201 A2 --- f_z [ ?/el] Flag for z
203-238 A36 --- inside Spatial notes on C1 (3)
240-275 A36 --- include Spatial notes on C1 (4)
277-288 A12 --- classC1 Source class for the C1 (5)
290-291 I2 h RAC1h ? Hour of Right Ascension (J2000)
293-294 I2 min RAC1m ? Minute of Right Ascension (J2000)
296-300 F5.2 s RAC1s ? Second of Right Ascension (J2000)
302 A1 --- DEC1- Sign of the Declination (J2000)
303-304 I2 deg DEC1d ? Degree of Declination (J2000)
306-307 I2 arcmin DEC1m ? Arcminute of Declination (J2000)
309-313 F5.2 arcsec DEC1s ? Arcsecond of Declination (J2000)
315-319 F5.2 mag B2magC1 [0/23]? USNO-B1 B magnitude for C1 (6)
321-325 F5.2 mag R2magC1 [0/25]? USNO-B1 R magnitude for C1 (6)
327-347 A21 --- C2 The second low-energy counterpart
349-410 A62 --- n_C2 Multifrequency notes for C2 (2)
412-428 A17 --- classC2 Source class for C2 (5)
430-431 I2 h RAC2h ? Hour of Right Ascension (J2000)
433-434 I2 min RAC2m ? Minute of Right Ascension (J2000)
436-440 F5.2 s RAC2s ? Second of Right Ascension (J2000)
442 A1 --- DEC2- Sign of the Declination (J2000)
443-444 I2 deg DEC2d ? Degree of Declination (J2000)
446-447 I2 arcmin DEC2m ? Arcminute of Declination (J2000)
449-453 F5.2 arcsec DEC2s ? Arcsecond of Declination (J2000)
455-459 F5.2 --- B2magC2 [0/21.2]? USNO-B1 B magnitude for C2 (6)
461-465 F5.2 --- R2magC2 [0/26]? USNO-B1 R magnitude for C2 (6)
467-471 F5.1 % Pbzb ? Probability of C1 as BL Lac (BZB) (7)
473-476 F4.1 % Pbzq ? Probability of C1 as BZQ (8)
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Note (1): Gamma-ray source category as follows (see section 2 for details):
I = identified;
A = associated;
C = candidate;
U = unidentified.
Note (2): Symbols used for the multifrequency notes n_C1, n_C2 are
reported in Section 5, table 3, as:
---------------------------------------------------------------------------
Symbol Comment
---------------------------------------------------------------------------
b PSR in a binary system
e PSR detected in γ rays by the Compton γ-ray Observatory
g PSR discovered in LAT γ-ray data
m MSP (millisecond pulsar)
p Pulsar discovered by the Pulsar Search Consortium (PSC)
r PSR discovered in the radio
u PSR discovered using a Fermi-LAT seed position
x PSR discovered in X-rays
---------------------------------------------------------------------------
See the optical spectra references in refs.dat file.
Note (3): Spatial notes if the first low-energy counterpart lies inside
of a sfr/snr/pwn (see Note (5) below)
Note (4): Spatial notes if the first low-energy counterpart includes
a psr/msp (milli-second pulsar).
Note (5): Classification as follows:
unc = Unclassified sources (411 sources + 8 in sfr)
ugs = Unidentified γ-ray source (394 sources)
bzq = Quasar radio loud with flat radio spectrum (351 sources)
bzb = BL Lac object (297 sources)
bzu = Blazar of uncertain type (57 sources)
bcn = Blazar candidate (286 sources)
sfr = Star-forming-HII region (90 sources)
psr = Pulsar (88 sources + 23 in pulsar wind nebula (pwn) and 7 in snr)
msp = Millisecond pulsar (51 sources)
snr = Supernova remnant (79 sources + 12 with psr)
gal = Normal galaxy (11 sources)
rdg = Radio galaxy (10 sources)
sbg = Starburst galaxy (3 sources)
sey = Seyfert galaxy (3 sources)
glc = Globural cluster (10 sources + 1 in sfr and 1 with psr)
pwn = Pulsar wind nebula (6 sources + 6 with psr)
hmb = High mass X-ray binary (2 sources + 3 in sfr)
bin = Binary star (1 source)
Note (6): USNO-B1 magnitudes reported only for classC1 or classC2 sources
with values of "bcn" or "unc".
Note (7): Probability that the first low-energy counterpart (C1) has
infrared colors similar to the known 1FGL BZBs estimated with the KDE
method (see Section 7 for details).
Note (8): Probability that the first low-energy counterpart (C1) has
infrared colors similar to the known 1FGL BZQ (quasar with flat radio
spectrum, see Note (5) above) estimated with the KDE method (see
Section 7 for details).
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Ref Reference code
18- 36 A19 --- BibCode Bibcode if any
38- 57 A20 --- Aut Author's name(s)
59-119 A61 --- Comm Comment
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Apr-2015