J/A+A/683/A112 Large Quasar Astrometric Catalogue 6, LQAC-6 (Souchay+, 2024)
LQAC-6: Sixth Release of the Large Quasar Astrometric Catalogue.
A compilation of 2 073 099 objects with 1 739 187 Gaia DR3 counterparts.
Souchay J., Secrest N., Sexton R., Barache C.
<Astron. Astrophys. 683, A112 (2024)>
=2024A&A...683A.112S 2024A&A...683A.112S (SIMBAD/NED BibCode)
ADC_Keywords: Combined data ; Cross identifications ; Active gal. nuclei ;
Photometry ; Positional data ; Redshifts ; Magnitudes, absolute ;
Morphology
Keywords: catalogs - surveys - astrometry - quasars: general
Abstract:
In addition to being objects of intense interest for cosmology and
studies of the evolution of the universe, quasars are used to define
quasi-inertial positions on the celestial sphere. Since its first
publication in 2009, the purpose of the Large Quasar Astrometric
Catalogue (LQAC) has been to provide the largest catalogue of bona
fide quasars suitable for astrometry, with the high-precision
positions from Gaia becoming available in the fourth release (LQAC-4).
Following the same kind of procedure as in the previous releases of
the LQAC, our aim is to compile the maximum number of recorded
quasars, with optimised equatorial coordinates and fundamental
information about their physical properties such as the redshift, the
photometry, radio fluxes, morphological index.
New quasars from the SDSS DR16Q release were cross-matched with the
precedent LQAC-5 compilation with a 1" radius, which leads to 225082
objects not present in the previous LQAC-5 release. Another
cross-match was done with the Gaia Celestial Reference Frame 3 (GCRF3)
catalogue, which is itself a compilation of a large number of quasars
catalogues, accompanied with very accurate Gaia DR3 positions.
Moreover, AGN's coming from 19 individual extragalactic surveys not
considered in the previous LQAC compilations are added.
This new LQAC-6 release contains 2073099 objects, which is 3.5 times
the number of objects recorded in the previous LQAC-5 release. Among
them, 1739187 objects were found in common with the Gaia DR3, within
a 1" search radius. A large part of new objects belong to the GCRF3
catalogue, which gathers a total number of 1614218 objects.
The LQAC-6 delivers a nearly complete catalogue of quasars and AGN's
to the astronomical community, with the aim of giving their best
equatorial coordinates with respect to the recent ICRF3 and with
exhaustive additional information. For as much as 83.9% of the sample,
these coordinates are extracted from the very recent Gaia DR3.
Description:
Following the same kind of procedure as in the previous releases of
the LQAC, our aim is to compile the maximum number of recorded
quasars, with optimised equatorial coordinates and fundamental
information about their physical properties such as the redshift, the
photometry, radio fluxes, morphological index.
This new LQAC-6 release contains 2073099 objects, which is 3.5 times
the number of objects recorded in the previous LQAC-5 release. Among
them, 1739187 objects were found in common with the Gaia DR3, within
a 1" search radius. A large part of new objects belong to the GCRF3
catalogue, which gathers a total number of 1614218 objects.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
lqac6.dat 827 2073099 6th release of LQAC
--------------------------------------------------------------------------------
See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/284 : The USNO-B1.0 Catalog (Monet+ 2003)
I/305 : The Guide Star Catalog, Version 2.3.2 (GSC2.3) (STScI, 2006)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/282 : SDSS Photometric Catalog, DR7 (Adelman-McCarthy+, 2007)
II/294 : The SDSS Photometric Catalog, DR7 (Adelman-McCarthy+, 2009)
VII/279 : SDSS quasar catalog: twelfth data release (Paris+, 2017)
VII/241 : The 2dF QSO Redshift Survey (Croom+ 2004)
VIII/71 : The FIRST Survey Catalog, Version 03Apr11 (Becker+ 2003)
VII/158 : Revised and Updated Catalog of QSO (Hewitt+ 1993)
VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)
VIII/60 : Interferometer phase calibration sources (Patnaik+ 1998)
I/323 : International Celestial Reference Frame 2, ICRF2 (Ma+, 2009)
J/ApJS/141/13 : First VLBA calibrator survey: VCS1 catalog (Beasley+, 2002)
J/AJ/126/2562 : Second VLBA calibrator survey: VCS2 (Fomalont+, 2003)
J/AJ/129/1163 : Third VLBA calibrator survey: VCS3 (Petrov+, 2005)
J/AJ/131/1872 : Fourth VLBA calibrator survey: VCS4 (Petrov+, 2006)
J/AJ/136/580 : Sixth VLBA calibrator survey: VCS6 (Petrov+, 2008)
J/MNRAS/372/425 : 2dF-SDSS Luminous Red Galaxy Survey, 2SLAQ (Cannon+, 2006)
J/MNRAS/392/19 : The 2dF-SDSS QSO survey (Croom+, 2009)
J/AJ/151/154 : Second epoch VLBA Calibrator Survey (VCS-II) (Gordon+, 2016)
J/MNRAS/414/2528 : LBA Calibrator Survey (LCS1) (Petrov+, 2011)
J/AJ/142/35 : The VLBA Galactic Plane Survey (VGaPS) (Petrov+, 2011)
J/AJ/142/89 : Precise astrometry with VLBA (VIPS) (Petrov+, 2011)
J/ApJS/188/405 : Fermi-LAT first source catalog (1FGL) (Abdo+, 2010)
J/ApJS/194/25 : VLBA calibrator search for the BeSSeL survey (Immer+, 2011)
J/MNRAS/419/1097 : The EVN Galactic Plane Survey - EGaPS (Petrov, 2012)
http://www.aoc.nrao.edu/~gtaylor/csource.html : VLA catalog
J/ApJS/221/12 : AGNs in the MIR using ALLWISE data (Secrest+, 2015)
J/A+A/494/799 : Large Quasar Astrometric Catalogue (LQAC) (Souchay+, 2009)
J/A+A/537/A99 : Large Quasar Astrometric Catalogue 2 (LQAC-2) (Souchay+, 2012)
J/A+A/583/A75 : Large Quasar Astrometric Catalogue 3 (LQAC-3) (Souchay+, 2015)
J/A+A/614/A140 : Large Quasar Astrometric Catalogue 4 (LQAC-4) (Souchay+, 2018)
J/A+A/624/A145 : Large Quasar Astrometric Catalogue 5 (LQAC-5) (Souchay+, 2019)
Byte-by-byte Description of file: lqac6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
4- 10 I7 --- LQACN Source number order in lqac-6
16- 31 A16 --- LQAC5 LQAC-5 name given for each object based on
equatorial coordinates
34 I1 --- LQACDet First LQAC detected Flag to recognize
already recorded or new sources (1)
36- 66 A31 --- OName Name of the quasar in the original
catalog or original catalog name (2)
68- 73 A6 --- Nature Nature of the object (3)
76-108 A33 --- CatFlags Flags indicating the presence of the
quasar in the catalogs belonging to the
compilation (8)
111-115 F5.3 --- GaiaDR3Prob ?=0 Quasar probability in Gaia-DR3 (9)
119-120 I2 --- GaiaDR3Obs Number of Observations in Gaia-DR3
123-127 A5 --- GRF3Flag Presence in Gaia GCRF3 (13)
130-141 A12 --- DR3Class ?=0 Classification of quasar given in
GAIA DR3
149-162 F14.10 deg RAOdeg Right ascension (J2000) in original
catalog or ICRS, Ep=2016.0 for
new sources GCRF3 (4)
165-178 F14.10 deg DEOdeg Declination (J2000) in original catalog or
ICRS, Ep=2016.0 for new sources GCRF3 (4)
180-184 A5 --- Source Source of the following optimized
equatorial coordinates (5)
187-200 F14.10 deg RAdeg Optimized Right ascension (J2000) or
ICRS Ep=2016 for Source=DR3 (6)
203-216 F14.10 deg DEdeg Optimized Declination (J2000) or
ICRS Ep=2016 for Source=DR3 (6)
226-239 F14.10 deg RAGdeg ?=0 Right ascension in GaiaDR3
(ICRS, Ep=2016.0)
241-247 F7.4 mas e_RAGdeg ?=0 Uncertainity in (alpha)xcos(delta) in
Gaia DR3 (7)
252-265 F14.10 deg DEGdeg ?=0 Declination in Gaia DR3
(ICRS, Ep=2016.0)
267-273 F7.4 mas e_DEGdeg ?=0 Uncertainty in delta in Gaia DR3 (7)
277-283 F7.4 --- rho1 ?=0 Correlation right ascension and
declination
287-293 F7.4 mas epos ?=0 Sigma position
301-308 F8.4 mas plx ?=0 Parallax in Gaia DR3
312-318 F7.4 mas e_plx ?=0 Uncertainty Parallax in Gaia DR3
320-328 F9.4 mas/yr pmRA ?=0 Proper Motion in Right ascension in
Gaia DR3 (mu_alpha x cos delta)
333-338 F6.4 mas/yr e_pmRA ?=0 Uncertainty in Proper Motion in
Right ascension in Gaia DR3
340-348 F9.4 mas/yr pmDE ?=0 Proper Motion in Declination in
Gaia DR3
353-358 F6.4 mas/yr e_pmDE ?=0 Uncertainty in Proper Motion in
Declination in Gaia DR3
362-368 F7.4 --- rho2 ?=0 Correlation between proper motion in
right ascension and proper motion in
declination
371-378 F8.4 mas/yr pmtot ?=0 Total proper motion
380-388 F9.4 --- pmChi ?=0 Chi Proper Motion
396-402 F7.4 mag Gmag ?=0 Photometric magnitude in Optical G
in Gaia DR3 band
405-411 F7.4 mag BPmag ?=0 Photometric magnitude in Optical BP
in Gaia DR3 band
414-420 F7.4 mag RPmag ?=0 Photometric magnitude in Optical RP
in Gaia DR3 band
432-439 F8.5 --- zorigin ?=0 Redshift in Original catalogue
442-448 F7.5 --- zDR3 ?=0 Redshift Nominal Gaia DR3
451-457 F7.5 --- b_zDR3 ?=0 Redshift Minimum Gaia DR3
460-466 F7.5 --- B_zDR3 ?=0 Redshift Maximum Gaia DR3
471-485 A15 --- PhotFlags Flags Photometry (14)
490-495 F6.3 mag FUV ?=0 F UV FLUX (AB) magnitude
500-505 F6.3 mag XNUV ?=0 XN UV FLUX (AB) magnitude
510-515 F6.3 mag umag ?=0 Photometric magnitude in Optical u
band between 300 and 400 nm (10)
520-525 F6.3 mag gmag ?=0 Photometric magnitude in Optical g
band between 400 and 500 nm (10)
530-535 F6.3 mag rmag ?=0 Photometric magnitude in Optical r
band between 600 and 750 nm (10)
540-545 F6.3 mag imag ?=0 Photometric magnitude in Optical i
band between 750 and 1000 nm (10)
550-555 F6.3 mag zmag ?=0 Photometric magnitude in Optical z
band between 800 and 1000 nm (10)
560-565 F6.3 mag Ymag ?=0 Photometric magnitude in Optical Y
band between 500 and 600 nm (10)
573-578 F6.3 mag Jmag ?=0 Photometric magnitude in Infrared J
band between 1000 and 1500 nm (11)
583-588 F6.3 mag Hmag ?=0 Photometric magnitude in Infrared H
band between 1500 and 2000 nm (11)
593-598 F6.3 mag Kmag ?=0 Photometric magnitude in Infrared K
band between 2000 and 3000 nm (11)
603-608 F6.3 mag W1mag ?=0 Photometric magnitude in Infrared W1
band 3.4 um (12)
613-618 F6.3 mag W2mag ?=0 Photometric magnitude in Infrared W2
band 4.6 um (12)
623-628 F6.3 mag W3mag ?=0 Photometric magnitude in Infrared W3
band 12 um (12)
633-638 F6.3 mag W4mag ?=0 Photometric magnitude in Infrared W4
band (W4) 22 um (12)
647-651 F5.3 mJy S15 ?=0 Radio flux between 100 and 200MHz
657-661 F5.3 mJy S84 ?=0 Radio flux between 750 and 1500MHz
666-671 F6.3 mJy S90 ?=0 Radio flux between 750 and 1500Mhz
676-681 F6.3 mJy S14 ?=0 Radio flux between 750 and 1500MHz
686-691 F6.3 mJy S3 ?=0 Radio flux between 1500 and 3000MHz
699-704 F6.3 --- I1B ?=-9.9 Sharp morphology index in band B
709-714 F6.3 --- I2B ?=-9.9 Sround morphology index in band B
719-724 F6.3 --- I3B ?=-9.9 Ground morphology index in band B
729-734 F6.3 --- I1R ?=-9.9 Sharp morphology index in band R
739-744 F6.3 --- I2R ?=-9.9 Sround morphology index in band R
749-754 F6.3 --- I3R ?=-9.9 Ground morphology index in band R
759-764 F6.3 --- I1I ?=-9.9 Sharp morphology index in band I
769-774 F6.3 --- I2I ?=-9.9 Sround morphology index in band I
779-784 F6.3 --- I3I ?=-9.9 Ground morphology index in band I
792-797 F6.2 mag uMAG ?=-9.9 Absolute magnitude in band u
802-807 F6.2 mag gMAG ?=-9.9 Absolute magnitude in band g
812-817 F6.2 mag rMAG ?=-9.9 Absolute magnitude in band r
822-827 F6.2 mag iMAG ?=-9.9 Absolute magnitude in band i
--------------------------------------------------------------------------------
Note (1): Flag to recognize already recorded or new source as follows:
3 = that the sources have been already recorded in LQAC-3
4 = that the sources have been already recorded in LQAC-4
5 = that the sources have been already recorded in LQAC-5
6 = that the sources is a new entry within the LQAC-6
Note (2): This field may contain white spaces.
Note (3): The nature of the object is generally a QSO, noted "QUASAR".
It is "RADIO" when observed in VLBI and not belonging to the ICRF3.
It is "ICRF3" when included in ICRF3.
It is "BL LAC" or "AGN" when this terminology is found
in Veron-Cetty and Veron (2010, Cat. VII/258)
This field may contain white spaces.
Note (4): The RA, DE are the coordinates of the quasar according to the original
catalog where it has been found (J2000) except for astro sources taken
in Gaia DR3(GRF3) and added to LQAC-3 (------N) where Epoque=2016.0.
These two coordinates are given in degree, with a precision of
1x10^-10 (i.e. 36 microarcseconds).
Note that no quasar, even belonging to the ICRF3, GAIA-DR3
or GAIA-DR2 guarantees this level of accuracy.
This justifies that in many cases, final digits have a zero value.
Note (5): Source of the following optimized equatorial coordinates as follows:
ORIG = means the optimized coordinates are taken from the original
catalogue with the best astrometric precision ;
DR1 = means they are taken from Gaia-DR1
(Gaia Collaboration, 2016A&A...595A...1G 2016A&A...595A...1G, Cat. I/337) ;
DR2 = means they are taken from Gaia-DR2
(Gaia Collaboration, 2018A&A...616...1G, Cat. I/345) ;
DR3 = means they taken from Gaia-DR3
(Gaia Collaboration, 2023A&A...674...A1, Cat. I/355) ;
ICRF = means they are taken from the ICRF2 catalogue
(Ma+, 2009ITN....35....1M 2009ITN....35....1M, Cat. I/323) ;
LQRF = means they are recalculated in the LQRF
(Andrei et al., 2009A&A...505..385A 2009A&A...505..385A, Cat. I/313)
Note (6): The RA, DE are the coordinates of the quasar according to the original
catalog where it has been found at J2000 except for astro sources taken
in Gaia DR3 (GRF3) and added to LQAC-3 (------N) where Epoque=2016.0.
These two coordinates are given in degree, with a precision of
1x10^-10 (i.e. 36 microarcseconds).
Note that no quasar, even belonging to the ICRF3 or GAIA-DR3,
guarantees this level of accuracy.
This justifies that in many cases, final digits have a zero value.
Note (7): Numerous original catalogues do not provide uncertainties on the
quasar equatorial coordinates. The uncertainties taken
from the Gaia-DR1 or Gaia-DR2 or Gaia-DR3 catalogues are then a precious
information about the position accuracy, when available.
Note (8): The catalogs flags (taken in order for sources coordinates
for astro catalogue are the following ones :
A = ICRF3 (Ma et al., 2009, IERS, Technical Note No. 35)
B = RFC (Petrov http://astrogeo.org/rfc/ version 2016)
C = VLA (Cat. J/ApJS/141/13, J/AJ/126/2562, J/AJ/129/1163, J/AJ/131/1872)
D = JVAS (Patnaik et al., Cat. VIII/60)
E = SDSS (combination DR7Q-DR12Q, https://www.sdss.org/dr7/ -
https://www.sdss3.org/dr12/, Paris+, 2017A&A...597A..79P 2017A&A...597A..79P,
Cat. VII/279, 2017yCat.7278....0P 2017yCat.7278....0P)
F = 2QZ (Croom et al., Cat. VII/241)
G = 2df-SDSS (2df-SDSS LRG and QSO survey, 2009);
da Angela et al., 2008MNRAS.383..565D 2008MNRAS.383..565D;
LRG: Cannon et al., Cat. J/MNRAS/372/425;
QOS: Croom et al., Cat. J/MNRAS/392/19
H = FIRST (Becker et al., Cat. VIII/71)
I = Hewitt and Burbridge, Cat. VII/158
J = 2MASS (only for magnitude information) (Cutri et al., Cat. II/246)
K = GSC2.3 (only for magnitude information) (Lasker et al., Cat. I/305)
L = B1.0 (only for magnitude information) (Monet et al., Cat. I/284)
M = Veron-Cetty and Veron (2010, Cat. VII/258)
N = GCRF3 (Gaia Collaboration et al., 2022A&A...667A.148G 2022A&A...667A.148G)
O = LAMOST
P = GAMA (Driver et al., 2022MNRAS.513..439D 2022MNRAS.513..439D)
Q = VIPERS (Scodeggio et al., 2018, Cat. J/A+A/609/A84)
R = MQS (Kozowski et al., 2013, Cat. J/ApJ/775/92)
S = DEEP (Newman et al., 2013ApJS..208....5N 2013ApJS..208....5N) and
(Cooper et al., 2012MNRAS.419.3018C 2012MNRAS.419.3018C)
T = AGES (Kochanek et al., 2012, Cat. J/ApJS/200/8)
U = ZCAT
V = WIGZ (Drinkwater et al. 2018, Cat. J/MNRAS/474/4151)
W = 2SLAQ (Croom et al., 2009, Cat. J/MNRAS/392/19)
X = 6df (Jones et al., 2009MNRAS.399..683J 2009MNRAS.399..683J, Cat. VII/259)
Y = COSMOS (Trump et al., 2007, Cat. J/ApJS/172/383)
Z = PRIMUS (Coil et al., 2011ApJ...741....8C 2011ApJ...741....8C)
a = GPQ (Fu et al. 2021, Cat. J/ApJS/254/6)
b = HQS (Hagen et al., 1999, Cat. J/A+AS/134/483)
c = OCARS (Malkin, 2018ApJS..239...20M 2018ApJS..239...20M)
d = HES (Wisotzki et al., 2000, Cat. J/A+A/358/77)
e = QBRICS (Calderone et al., 2019, Cat. J/ApJ/887/268)
f = MGC (Liske et al., 2003MNRAS.344..307L 2003MNRAS.344..307L, Cat. VII/240)
g = VVDS (Garilli et al., 2008A&A...486..683G 2008A&A...486..683G)
Note (9): Probability only for Gaia Reference sources DR3 (GRF3).
Overall class Probability from DSC of being a quasar.
0.0 is none.
1.0 is 100 percent
For all other sources from other astrometry catalogues
their probability is 100 percent.
Note (10): For each bandwidth the photometric systems in which the magnitudes
have been measured are not homogeneous, the priority being indicated
by the catalog flag letter in decreasing alphabetic order.
Note (11): Coming from 2MASS (Cutri et al., Cat. II/246)
Note (12): Coming from AGNs in the MIR (mid infra-red)
using ALLWISE data (Secrest et al., 2015, Cat. J/ApJS/221/12)
Note (13): Field value is GCRF3 or Blank for None.
Note (14): Flag Photometric origin catalogues in a 15 characters
column for 15 photometry :
FUV, NUV, u, g, r, i, z, y, J, H, K, W1, W2, W3, W4
A: GALEX
B: SDSS
C: DES
D: Pan-STARRS
E: SkyMapper
F: 2MASS XSC
G: 2MASS PSC
H: UKIDSS
I: DENIS
K: AllWISE
L: CatWISE2020
--------------------------------------------------------------------------------
Acknowledgements:
Jean Sourchay, jean.souchay(at)obspm.fr,
SYRTE/Observatoire Paris/PSL/CNRS/Sorbonne Universite/LNE
61 avenue de l'Observatoire 75014 Paris
Nathan Secrest, nathansecrest(at)msn.com,
U.S. Naval Observatory, 3450 Massachusetts Avenue NW Washington,
DC 20392-5420, USA
Remington Sexton, rsexton2(at)gmu.edu,
U.S. Naval Observatory, 3450 Massachusetts Avenue NW Washington,
DC 20392-5420, USA
Christophe Barache, christophe.barache(at)obspm.fr,
SYRTE/Observatoire Paris/PSL/CNRS/Sorbonne Universite/LNE
61 avenue de l'Observatoire 75014 Paris
(End) Christophe Barache [SYRTE-Paris Obs.], Patricia Vannier [CDS] 30-Jan-2024