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VII/280          The Million Quasars (Milliquas) catalog (V5.2)   (Flesch, 2017)

The Million Quasars (Milliquas) catalogue, version 5.2. Flesch E.W. <Pub. Astron. Soc. Australia 32, 10 (2015)> =2015PASA...32...10F =2017yCat.7280....0F
ADC_Keywords: QSOs ; Active gal. nuclei ; Redshifts ; Magnitudes Keywords: catalogs - quasars: general Description: This is a compendium of 607,208 type-I QSOs and AGN, largely complete from the literature to 5-August-2017, including the release of SDSS-DR14. Also included are ∼1.35M high-confidence (80%+ likelihood) quasar candidates from the NBCKDE, NBCKDE-v3, XDQSO, AllWISE and Peters photometric quasar catalogs (citations in Note 7 below) and from all-sky radio/X-ray associated objects which are calculated here. Type-II and Bl Lac objects are also included, bringing the total count to 1,998,464. Changes from version 5.1 are: (1) SDSS-DR14 and SDSS-DR14Q have been added, using the processing rules from the Half Million Quasars catalog (HMQ: Flesch 2015PASA...32...10F). (2) WISE quasar candidates have been added from Secrest et al, 2015, Cat. J/ApJS/221/12; these are ∼430K candidates over the whole sky for which 2-color optical objects were found within a 2-arcsec radius. They have been processed into pQSOs from calibration against the SDSS-DR12Q multi-class superset, and photometric redshifts obtained using the four-color based method from the HMQ appendix 2. The four colors used were B-R, R-W1, W1-W2 & W2-W3. (3) Type-II narrow emission-line galaxies, (NELGs, class='N') are added as the luminosity class corresponding to the type-I AGN galaxies. High-luminosity type-II NLAGN (class='K') correspond to the type-I quasars. The NLAGN/NELG divider is the same luminosity/psf function which separates QSOs from AGNs. Type-II NELGs include unquantified contamination by LINERs and probably a few starbursts which eluded removal, so it serves as a catch-all category presented for completeness, rather than as a strict type-II class. (4) Small publications to 5 August 2017 have been added. (5) Positional fixes (of about 2 arcsec) have been applied to ∼150 objects. Low-confidence or questionable objects (so deemed by their researchers) are not included in Milliquas. Additional quality cuts can be applied as detailed in Flesch 2015PASA...32...10F). Multiple lensed images are excluded and only the brightest one kept. The aim here is to present one unique reliable object per each data row. The catalog format is simple, each object is shown as one line bearing the J2000 coordinates, its original name, object class, red and blue optical magnitudes, PSF class, redshift, the citations for the name and redshift, plus up to four radio/X-ray identifiers where applicable. This catalog can be cited as Milliquas, Flesch E., 2015PASA...32...10F which was the published version of this catalog as at 2015 after the release of SDSS-DR12. Questions/comments/praise/complaints may be directed to me at eric(at) File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file catalog.dat 192 1998464 The Milliquas catalogue, V5.2 (5 August 2017)
See also: VII/273 : The Half Million Quasars (HMQ) catalogue (Flesch, 2015) VII/277 : The Million Quasars (Milliquas) catalogue, V4.8 (Flesch, 2016) Byte-by-byte Description of file: catalog.dat
Bytes Format Units Label Explanations
1- 11 F11.7 deg RAdeg Right ascension (J2000) (1) 13- 23 F11.7 deg DEdeg Declination (J2000) (1) 26- 50 A25 --- Name ID from the literature, or J2000 (2) 52 A1 --- Cl [ABKQqN] classification of object (3) 53- 55 A3 --- Assoc [2RX ] Summary of associations for object (4) 57- 61 F5.2 mag Rmag Red optical magnitude (5) 63- 67 F5.2 mag Bmag Blue optical magnitude (5) 69- 71 A3 --- Comment Comment on optical object (6) 73 A1 --- R Red optical PSF class (7) 75 A1 --- B Blue optical PSF class (7) 77- 82 F6.3 --- z ? Redshift from the literature or estimated (8) 84- 89 A6 --- r_Name Citation for name (9) 91- 96 A6 --- r_z Citation for redshift (9) 98-100 I3 pct Qpct ? Probability that this object is a QSO (10) 102-123 A22 --- XName X-ray ID, if any (11) 125-146 A22 --- RName Radio ID, if any (11) 148-169 A22 --- Lobe1 Radio lobe ID or extra R/X ID, if any (11) 171-192 A22 --- Lobe2 Radio lobe ID or extra X-ray ID, if any (11)
Note (1): These are to 7 decimals which is too precise, but which accomodates a miniscule round-up which prevents inadvertent truncation by the user when converting to sexagesimal. Note (2): Nameless radio/X-ray associated objects here display the J2000 position in HHMMSS.SS+DDMMSS.S for the convenience of the user. If needing a name for it, just preface the J2000 with "MQ", e.g., MQ J000001.5-251706. Note (3): Classification of object as follows: Q = QSO, type I broad-line unresolved, 577146 of these. A = AGN, type I Seyferts/host-dominated, 30062 of these. B = BL Lac object, 1615 of these. q = photometric quasar candidate from SDSS or WISE, 1297111 of these. N = type-II narrow-line Seyfert/NELG galaxy, 38110 of these. This class includes an unknown number of LINERs, presented for completeness. K = type-II narrow-line NLAGN, quasar-like high luminosity, 1355 of these. Note (4): Summary of associations for object as follows: R = Radio association displayed. X = X-ray association displayed. 2 = Double radio lobes displayed (declared by data-driven algorithm). Note (5): Optical data is from the APM (, USNO-A & USNO-B (, and the SDSS ( APM/USNO-A magnitudes have been recalibrated from the original values as documented in QORG (2004,A&A,427,387), so such USNO-A magnitudes are often used in preference to USNO-B. APM galaxies < mag 17 are usually shown too bright due to PSF modelling. Integer magnitudes (e.g., 22.00) can be estimates if both bands are integer or one band empty. Note: many SDSS magnitudes are "extinction-corrected" ∼0.3 mag brighter than observed. Note (6): Comment on optical object legend as follows: p = optical magnitudes are POSS-I O (violet 4050Å) and E (red 6400Å). These are preferred because O is well-offset from E, and these plates were always taken on the same night, thus the red-blue color is correct even for variable objects. j = blue magnitude is SERC J (Bj 4850A blue-green) from the POSS-II or UKST surveys. Red-blue color is less reliable because the plates were taken in different epochs, i.e. years apart. g = blue magnitude is SDSS green 4900A, red is SDSS r 6200A. u = blue magnitude is SDSS ultraviolet 3850A. b = blue magnitude is Vega 4400A (Johnson). v = red magnitude is visual., ie, white, 5500A midpoint. i = red magnitude is infrared 7500A. z = red magnitude is infrared z 8500A. (not v/i/z) = standard red 6400A (Cousins). + = variability nominally detected in both red/blue, over multi-epoch data. m = proper motion nominally detected, from USNO-B. a = object is an SDSS galaxy with AGN subclass. If also BROADLINE then Milliquas class is 'A', otherwise 'N' (see note 3). ? = identification uncertain (quasar may be located elsewhere, 4 of these). Note (7): The APM, USNO-B, and SDSS provide PSF class, albeit using different criteria. These are shown here as follows: - = point source / stellar PSF (APM notation: -1, here truncated) 1 = fuzzy / galaxy shape (APM notation: 1 and some 2) n = no PSF available, whether borderline or too faint to tell, etc. x = not seen in this color (fainter than plate depth, or confused, etc.) Note (8): Photometric redshifts (for objects classified as 'q') are here rounded to 0.1 z. The XDQSO catalog does not provide photometric redshifts, so those are provided either by NBCKDE or by this catalog using the method detailed in Appendix 2 of my HMQ paper (2015PASA...32...10F). AllWISE photometric redshifts are similarly calculated using the four colors B-R, R-W1, W1-W2 and W2-W3, and are displayed where calculated as 50%+ likely to be true within 0.5z of the displayed redshift value -- usual likelihood is more like 80%. Note (9): Legend (with counts of name and redshift) and references: 2dF (366,232) : 2dF galaxy survey, Colless M. et al., 2001MNRAS.328.1039C, Cat. VII/250 2QZ (27515,24161) : Croom S.M. et al., 2004MNRAS.349.1397C, Cat. VII/241 2SLAQ (10388,8717) : Croom S.M. et al., 2009, Cat. J/MNRAS/392/19 3LAC (30,28) : FERMI AGN v3, Ackermann M. et al., 2015, Cat. J/ApJ/810/14 6dF (287,227) : 6dF galaxy survey, Jones D.H. et al., 2009MNRAS.399..683J, Cat. VII/259 AAOz (1491,1498) : AAOmega XXL-South: Lidman C. et al., 2016PASA...33....1L AGES (2047,2047) : AGES survey, Kochanek C.S. et al., 2012, Cat. J/ApJS/200/8 ATLAS (229,269) : Mao M.Y. et al., 2012, Cat. J/MNRAS/426/3334 BASS (15,124) : Swift-BAT AGN, Koss M. et al., 2017,arXiv:1707.08123, ApJ BQLS (9,9) : BOSS QSO lenses & pairs, More A. et al., 2016MNRAS.456.1595M C-COSM (180,180) : Chandra COSMOS IDs, Marchesi S. et al., 2016ApJ...817...34M ChaMP (191,188) : Trichas M. et al., 2012ApJS..200...17T DES (1,1) : Dark Energy hi-z, Reed S.L. et al., 2015MNRAS.454.3952R DPeake (7,3450) : Double-peaked NELGs, Ge J.-Q. et al., 2012, Cat. J/ApJS/201/31 DR12 (1628,5332) : Alam S. et al., 2015ApJS..219...12A,, Cat. V/147 DR12Q (233,415) : SDSS-DR12Q, Paris I. et al., 2017A&A...597A..79P, Cat. VII/279 DR14 (32900,40157) : Abolfathi B. et al., 2017,arXiv:1707.09322, data at DR14Q (512359,525951) : SDSS-DR14Q, Paris I. et al., 2017, in preparation, data at DR7 (6378,4872) : SDSS DR7, Abazajian K.N. et al., 2009ApJS..182..543A, files at DR7Q (2128,340) : SDSS Quasar DR7, Schneider D. et al., 2010AJ....139.2360S, Cat. VII/260 DUHIZ (2,2) : DECaLS-UKIRT hi-z, Wang F. et al., 2017ApJ...839...27W eHAQ (82,81) : Extended High AV, Krogager J.-K., 2016ApJ...832...49K GLDD (1,1) : Lensed QSO data-driven, Ostrovski F. et al., 2017MNRAS.465.4325O HAQ (2,2) : High AV serendipitous, Heintz K.E. et al., 2016AJ....152...13H HAQC (1,1) : High AV in COSMOS, Heintz K.E. et al., 2016A&A...595A..13H HMQ (28638,22897) : Half Million Quasars catalog, Flesch E., 2015PASA...32...10F, Cat. VII/273, references therein to the original authors & papers. IGMCP (10,10) : IGM close pairs, Rorai A. et al., 2017Sci...356..418R IMS (1, 1) : IR medium-deep hi-z, Kim Y. et al., 2015ApJ...813...35H IKEDA (1,1) : Ikeda H. et al., 2017, arXiv:1708.00314, ApJ accepted LAMOST (4314,3786) : LAMOST-DR3, LIDMAN (1,1) : SN Host Galaxy redshifts, Lidman C. et al., 2013PASA...30....1L LIRAS (168,158) : LoCuSS IR AGNs, Xu, L. et al., 2015, Cat. J/ApJS/219/18 MORX (49916,0) : Million Radio/X-ray Associations, Flesch E., 2016PASA...33...52F, Cat. V/148 MQ (3144,635633) : MILLIQUAS, original data in this catalog, Flesch E.,2017 MZZ (9,9) : Marano B., Zamorani G., Zitelli V., 1988MNRAS.232..111M NBCKDE (40679,40679) : Richards G.T. et al., 2009, Cat. J/ApJS/180/67 NBCKv3 (576782,576782): NBCKDE v3, Richards G.T. et al., 2015, Cat. J/ApJS/219/39 OVRLAP (5,5) : SDSS overlap hi-z QSOs, Jiang L. et al., 2015AJ....149..188J OzDES (664,638) : Dark Energy SN QSOs, Tie S.S. et al., 2017AJ....153..107T PETERS (12952,12952) : photo special, Peters C.M. et al., 2015ApJ...811...95P PGC (13548,8) : Principal Galaxy Catalogue, Paturel G. et al., 2003A&A...412...45P, Cat. VII/237 PS1 (63,63) : PAN-STARRS1 hi-z, Banados E. et al., Cat. J/ApJS/227/11 PSO (3,3) : PAN-STARRS z-dropouts, Venemans B.P. et al., 2015ApJ...801L..11V RLQ (4,3) : Tuccillo D./Gonzalez-Serrano J.I./Benn C.R., 2015, Cat. J/MNRAS/449/2818 RSG (1,1) : Dorn-Wallenstein T.Z. & Levesque E., 2017,arXiv:1701.07888 SDSSHI (6,6) : SDSS hi-z, Jiang L. et al., 2016ApJ...833..222J SFM201 (1,1) : Schulze S. et al., 2012A&A...546A..20S SHELLQ (33,33) : Subaru hi-z, Matsuoka Y. et al., 2017,arXiv:1704.05854, PASJ SUV (21,21) : SDSS-ULAS/VHS QSOs, Yang J. et al., 2017,AJ,153,184 SXDF (39,39) : Subaru-XMMDF redshifts, Simpson C. et al., 2012, Cat. J/MNRAS/421/3060 SXDS (310,309) : Subaru-XMMDF spectra, Akiyama M. et al., 2015PASJ...67...82A ULTRA (1,1) : Ultraluminous hi-z, Wu, X.-B. et al., 2015Natur.518..512W UVQS (433,517) : UV QSOs, Monroe T.R. et al., 2016,AJ,152,25 VAHIZ (2,2) : VST ATLAS hi-z, Carnall A.C. et al., 2015MNRAS.451L..16C VDES (8,8) : VISTA Dark Energy Qsos, Reed S.L. et al., 2017MNRAS.468.4702R VIKING (4,4) : VIKING IR, Venemans, G.A. et al., 2015MNRAS.453.2259V VIPERS (241,285) : VIPERS PDR-2, Scodeggio M. et al., 2016, arXiv:1611.07048 VMC (34,34) : Magellanic IR QSOs, Ivanov V.D. et al., 2016A&A...588A..93I WARREN (1,1) : Warren S.J. et al., 2017, in preparation WISEA (430999,0) : AllWISE QSO candidates, Secrest N. et al., 2015, Cat. J/ApJS/221/12 WISEHI (72,70) : Hi-z QSOs from WISE, Wang F. et al., 2016, Cat. J/ApJ/819/24 XDQSO (235694,0) : SDSS-XDQSO, Bovy J. et al., 2011ApJ...729..141B XLSS (307,120) : Stalin C.S. et al., 2010, Cat. J/MNRAS/401/294 XMSS (182,150) : Barcons X. et al., 2007, Cat. J/A+A/476/1191 XWAS (490,449) : Esquej P. et al., 2013, Cat. J/A+A/557/A123 The citation for the classification (e.g., that the object is a quasar) can be from either the name or redshift citation. Note (10): For a QSO candidate (type starting with q/R/X/2), this shows the percent chance that it is a QSO, based on photometric and/or radio/X-ray association analysis. Included candidates are those of 80%+ likelihood of being true quasars. For a known QSO (type=Q/A), Bl Lac type (type=B) or type-II (type=K/N), this shows the percent chance that the shown radio/X-ray detection(s) is truly associated to it. Candidates (objects without spectroscopic confirmation) consist of three separate classes of objects: (1) Photometric quasars from the SDSS-based NBCKDE/NBCKDE-v3/XDQSO/Peters quasar candidate catalogs. Those catalogs give pQSOs (calculated QSO probabilities) for their objects which however are not reported here; instead, I have calibrated those pQSOs against SDSS-DR12Q classified objects to produce these QSO likelihoods -- see appendix 1 of my HMQ paper (Flesch 2015PASA...32...10F) for details of the calibration method. (2) WISE-sourced candidates are presented by their authors with a bulk pQSO as an average figure, with no individual pQSOs given. These I have generated by matching WISE candidates to optical objects (within a two arcsecond radius) and then dividing them into four-color (the colors being B-R, R-W1, W1-W2 & W2-W3) subsets which are then calibrated against SDSS-DR12Q classified objects to yield the pQSO for each subset. (3) Radio/X-ray associated objects, totalling 53065 without any other attribution. The likelihoods of being a true QSO are calculated as described in the QORG paper (Flesch & Hardcastle, 2004A&A...427..387F, Cat. J/A+A/427/387). 69609 photometric quasars are also radio/X-ray associated, and the displayed probability figure combines the calibrated photometric QSO likelihood P1 and the radio/X-ray derived QSO likelihood P2 as P = 1/(1+((1-P1)*(1-P2))/(P1*P2)). Over all objects, using the probability as expected yield, the 1957384 type-I Milliquas objects will yield 1901076 actual type-I quasars/AGNs, so making this a true million quasars catalog. Note (11): Four columns of Radio/X-ray detections are presented: * 1st column: best X-ray detection (i.e. highest probability association). * 2nd column: best core Radio detection. * 3rd column: a radio lobe if the description (see note 3) shows a "2", otherwise this is an additional radio or X-ray detection. * 4th column: a radio lobe if the description (see note 3) shows a "2", otherwise this is an additional X-ray detection. Legend of Radio/X-ray detection prefixes and catalog home pages: FIRST: VLA FIRST survey, 13Jun05 version, NVSS: NRAO VLA sky survey, SUMSS: Sydney U. Molonglo, MGPS: Molonglo galactic plane survey, same attribution as SUMSS ROSAT catalogs home page:, for: - 1RXH: ROSAT HRI (high resolution imager) - 2RXP/2RXF: ROSAT PSPC (position sensitive proportional counter) - 1RXS: ROSAT RASS (all-sky survey, both bright & faint) 2RXS: 2nd RASS source catalog, Boller Th. et al., 2016,A&A,588,103 1WGA: White, Giommi & Angelini, CXO: Chandra Source Catalog v1.1, CXOG: Chandra ACIS source catalog, Wang S. et al., 2016,ApJS,224,40 CXOX: XAssist Chandra source list, 2XMM/2XMMi: XMM-Newton DR3, 3XMM: XMM-Newton DR7, XMMSL: XMM-Newton Slew Survey Release 2.0, same attribution as 3XMM XMMX: XAssist XMM-Newton source list, 1SXPS: Swift X-ray Point Source catalog, Optical field solutions are calculated from the raw source positions of all these catalogs as described in my MORX paper 2016PASA...33...52F.
Acknowledgements: If using this catalogue in published research, please so cite. The confirmed quasars of this catalog (to Jan 2015) were published as the Half Million Quasars (HMQ) catalog: Flesch E., 2015PASA...32...10F, which can be used as the citation. This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory,California Institute of Technology, under contract with the National Aeronautics and Space Administration. History: Copied at Contact: Eric Flesch, eric(at)
(End) Patricia Vannier [CDS] 21-Aug-2017
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