J/ApJ/939/117 New identifications of 4FGL sources with SPT-SZ (Zhang+, 2022)
New identifications and multiwavelength properties of extragalactic Fermi
gamma-ray sources in the SPT-SZ survey field.
Zhang L., Vieira J.D., Ajello M., Malkan M.A., Archipley M.A., Capota J.,
Foster A., Madejski G.
<Astrophys. J., 939, 117 (2022)>
=2022ApJ...939..117Z 2022ApJ...939..117Z
ADC_Keywords: Gamma rays; Millimetric/submm sources; Radio sources; Surveys;
Infrared; X-ray sources; Cross identifications
Keywords: Active galactic nuclei ; Blazars ; Gamma-ray sources ;
Radio loud quasars ; Relativistic jets ; Submillimeter astronomy
Abstract:
The fourth Fermi Large Area Telescope catalog (4FGL) contains
5064 γ-ray sources detected at high significance, but 26% of
them still lack associations at other wavelengths. The SPT-SZ survey,
conducted between 2008 and 2011 with the South Pole Telescope (SPT),
covers 2500deg2 of the southern sky in three millimeter-wavelength
(mm) bands and was used to construct a catalog of nearly 5000 emissive
sources. In this study, we introduce a new cross-matching scheme to
search for multiwavelength counterparts of extragalactic γ-ray
sources using a mm catalog. We apply a Poissonian probability to
evaluate the rate of spurious false associations and compare the
multiwavelength associations from the radio, mm, near-infrared, and
X-ray with 4FGL γ-ray sources. In the SPT-SZ survey field, 85%
of 4FGL sources are associated with mm counterparts. These mm sources
include 94% of previously associated 4FGL sources and 56% of
previously unassociated 4FGL sources. The latter group contains
40 4FGL sources for which SPT has provided the first identified
counterparts. Nearly all of the SPT-associated 4FGL sources can be
described as flat-spectrum radio quasars or blazars. We find that the
mm band is the most efficient wavelength for detecting γ-ray
blazars when considering both completeness and purity. We also
demonstrate that the mm band correlates better to the γ-ray band
than the radio or X-ray bands. With the next generation of CMB
experiments, this technique can be extended to greater sensitivities
and more sky area to further complete the identifications of the
remaining unknown γ-ray blazars.
Description:
We use multiwavelength data to associate and characterize the 282 4FGL
sources within the 2500deg2 SPT-SZ survey field (Figure 1).
X-ray data are from the ROSAT All-Sky Survey (RASS) Bright Source
Catalog (Voges+ 1999, IX/10) and the Faint Source Catalog
(Voges+ 2000, IX/29) at X-ray energies 0.1-2.4keV. See Section 2.2.
Infrared data are taken from the Wide-field Infrared Survey Explorer
(WISE) AllWISE Source Catalog at 3.4, 4.6, 12, and 22um (see II/328).
The angular resolution of WISE ranges from 6" to 12" from short to
long wavelengths. See Section 2.3.
Millimeter-wave point sources are from the 2500deg2 SPT-SZ survey
(Everett+ 2020, J/ApJ/900/55), which has a spatial resolution of 1.15'
at 150GHz (2mm) and an absolute astrometric uncertainty of 2".
See Section 2.4.
Radio data are from the Sydney University Molonglo Sky Survey (SUMSS;
Mauch+ 2003, VIII/81) at 843MHz with 45" angular resolution and a
detection threshold of 6mJy. The data were taken between 1997 and
2003.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 87 317 282 4FGL sources within 2500deg2 SPT-SZ
survey field
table3.dat 157 432 Full 4FGL multi-wavelength association
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See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)
VIII/78 : Sydney University Molonglo Sky Survey (SUMSS) (Mauch+ 2006)
VIII/81 : Sydney University Molonglo Sky Survey (SUMSS V2.1) (Mauch+ 2008)
II/328 : AllWISE Data Release (Cutri+ 2013)
VII/274 : The Roma BZCAT - 5th edition (Massaro+, 2015)
J/MNRAS/380/199 : SCUBA Half-Degree Extragalactic Survey. III (Ivison+, 2007)
J/ApJS/175/97 : CGRaBS: survey of γ-ray blazar cand. (Healey+, 2008)
J/ApJ/719/763 : Millimeter-wave sources in the SPT survey (Vieira+, 2010)
J/MNRAS/413/2314 : Radio & mid-IR counterpart of submm galaxies (Biggs+, 2011)
J/ApJ/748/68 : WISE IR colors of gamma-ray blazars (D'Abrusco+, 2012)
J/ApJS/217/4 : 2FGL sources observed between 5-9GHz (Schinzel+, 2015)
J/ApJ/851/33 : Multi-wavelength analysis of CGRaBS blazars (Paliya+, 2017)
J/ApJ/838/139 : Radio follow-up on 3FGL unassoc. sources (Schinzel+, 2017)
J/ApJS/247/33 : Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)
J/ApJ/900/55 : The SPT-SZ catalog at 95, 150, and 220GHz (Everett+, 2020)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [0/281] Index number (G1)
5- 8 A4 --- --- [4FGL]
10- 21 A12 --- 4FGL 4FGL catalog identifier (JHHMM.m+DDMM)
23 A1 --- f_4FGL [n] Flag on 4FGL (G2)
25- 30 F6.1 10-13mW/m2 S0.1-100 [6.9/1993] 4FGL flux between 0.1-100GeV
32- 35 F4.1 10-13mW/m2 e_S0.1-100 [1.8/26] Uncertainty in S0.1-100
37- 57 A21 --- SPT-S SPT catalog identifier (JHHMMSS+DDMM.m +
SPT-S or FSPT-S) (G3)
59- 64 F6.1 mJy S150 [0.7/4843]? Flux density at 150GHz
66- 70 F5.1 mJy e_S150 [0.3/970.2]? Uncertainty in S150
72- 76 F5.2 arcmin dr1 [0.06/22.1]? Source separation
78- 81 F4.2 --- dr2 [0.08/3.8]? Source separation in σ
of the 4FGL positional uncertainty
83- 87 F5.2 [-] logP [-8.54/-1.07]? log probability of false
association
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [0/281] Index number (G1)
5- 8 A4 --- --- [4FGL]
10- 21 A12 --- 4FGL 4FGL catalog identifier (JHHMM.m+DDMM)
23 A1 --- f_4FGL [n] Flag on 4FGL (G2)
25- 45 A21 --- SPT-S SPT catalog identifier (JHHMMSS+DDMM.m + SPT-S
or FSPT-S) (G3)
47- 58 F12.8 deg RAdeg ? SPT Right Ascension in decimal degrees (J2000)
60- 69 F10.6 deg DEdeg ? SPT Declination in decimal degrees (J2000)
71- 76 F6.1 mJy S95 [0.5/5959]? Deboosted 95GHz flux density
78- 83 F6.1 mJy S150 [0.7/4843]? Deboosted 150GHz flux density
85- 90 F6.1 mJy S220 [2/3906]? Deboosted 220GHz flux density
92- 98 F7.5 --- z [2e-05/2.9]? Measured redshift from NED
if available
100-115 A16 --- 1RXS RASS catalog identifier (JHHMMSS.s+DDMMSS)
117-121 A5 --- --- [SUMSS ]
123-136 A14 --- SUMSS SUMSS catalog identifier (JHHMMSS+DDMMSS)
138-157 A20 --- WISEA AllWISE catalog identifier (JHHMMSS.ss+DDMMSS.s)
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Global notes:
Note (G1): The index is based on the sequence of the energy flux
(100MeV-100GeV) from high to low.
Note (G2): Flag as follows:
n = source has no associated counterpart in the original 4FGL catalog.
Note (G3): Of the 239 4FGL-SPT matches, 204 sources are detected at >4.5σ
in Everett+ (2020, J/ApJ/900/55), while the remaining 35 have had mm
fluxes assigned using forced photometry using the SUMSS (see VIII/81)
position as a prior. For clarity, these sources are highlighted in
Figures 7 and 8, labeled as FSPT for "faint".
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 11-Sep-2024