Browse
this table...

MORX - Million Optical/Radio/X-Ray (MORX) Associations Catalog

HEASARC
Archive

Overview

The Million Optical Radio/X-ray Associations (MORX) catalog combines all of the largest published optical, radio, and X-ray sky catalogs to find probable radio/X-ray associations with optical objects, plus double radio lobes, using uniform processing against all input data. This catalog contains 3,101,306 optical objects. Each object is displayed with J2000 astrometry, optical and radio/X-ray identifiers, red and blue photometry, and the calculated probabilities and optical field solutions for the associations.

MORX is a compendium of optical objects which are calculated as being associated with Chandra, XMM-Newton, Swift, or ROSAT X-ray sources, or with NVSS, FIRST, VLASS, LoTSS, RACS, or SUMSS radio sources or double radio lobes. All have likelihoods in the range of 40-100% confidence in their associations. The counts of the associations for this main sample are as follows:

    Optical objects (rows in this catalog) - 3,101,306
    Chandra - 102,717 X-ray associations
    XMM-Newton - 254,266 X-ray associations
    Swift - 91,471 X-ray associations
    ROSAT - 32,005 X-ray associations
    XMM Slew - 11,543 X-ray associations
    VLASS - 440,365 core radio associations, plus 15,783 double radio lobes(*)
    LoTSS - 1,807,441 core radio associations, plus 73,021 double radio lobes
    RACS - 590,145 core radio associations, plus 12,188 double radio lobes
    FIRST - 275,808 core radio associations, plus 8985 double radio lobes
    NVSS - 318,272 core radio associations, plus 672 double radio lobes
    SUMSS - 48,887 core radio associations, plus 42 double radio lobes
(*) Lobe pairs are presented once only, so not from multiple radio surveys.

For each optical object, the J2000 coordinates, object name if any, object class, red and blue photometry, redshift if any, likelihoods of the presented associations and calculated odds that the object is a quasar, galaxy, or star, and any radio and/or X-ray identifications are given. Also, given are references for the object name and redshift.

The radio/X-ray source prefixes, and their source catalog home pages that are cited in this table, are as follows:

     FIRST: VLA FIRST survey, 13Jun05 version, https://sundog.stsci.edu
     VLA (abbrev of VLASS1QLCIR): VLASS Quick Look, https://cirada.ca/catalogues
     RACS: Rapid ASKAP Continuum Survey, 2021,PASA,38,58, main source file
     RACD: RACS as above, but from their main detection ("Gaussian") file
     ILT:  LoTSS (LOFAR Two-metre Sky Survey), 2022,A&A,659,A1, main source file
     ILD:  LoTSS as above, but from their main detection ("Gaussian") file
     NVSS: NRAO VLA sky survey, https://www.cv.nrao.edu/nvss
     SUMSS: Sydney U. Molonglo, http://www.astrop.physics.usyd.edu.au/sumsscat/
     MGPS: Molonglo galactic plane, www.astrop.physics.usyd.edu.au/mgpscat/
     ROSAT catalogs:
        1RXH: ROSAT HRI (high resolution imager) as catalog IX/28A, and
        PSPC: (position sensitive proportional counter) as catalog IX/30 at
              http://cdsarc.cds.unistra.fr/cats/IX.htx
        2RXF: https://heasarc.gsfc.nasa.gov/W3Browse/rosat/rospspcftot.html
        1WGA: White, Giommi & Angelini, https://heasarc.gsfc.nasa.gov/wgacat/
        RASS is not included as its low resolution is not usable in isolation
     CXOG: Chandra ACIS source catalog, Wang S. et al., 2016,ApJS,224,40
     CXO:  Chandra Source Catalog v1.1, https://cxc.harvard.edu/csc
     2CXO: Chandra Source Catalog v2, https://cxc.harvard.edu/csc
     CXOX: XAssist Chandra source list, https://asd.gsfc.nasa.gov/xassist/
     2XMM/2XMMi: XMM-Newton DR3, http://cdsarc.cds.unistra.fr/cat/?IX/41
     4XMM: XMM-Newton DR12, https://www.cosmos.esa.int/web/xmm-newton/xsa
     XMMSL: XMM-Newton Slew Survey Release 2.0, same attribution as 4XMM
     XMMX: XAssist XMM-Newton source list, https://asd.gsfc.nasa.gov/xassist/
     2SXPS: Swift X-ray Point Source catalog, https://www.swift.ac.uk/2SXPS

Catalog Bibcode

2016PASA...33...52F

References

The Million Optical Radio/X-ray Associations (MORX) catalogue.
    Flesch E.W.
    <Publ. Astron. Soc. Australia, 33, 52 (2016)>
    =2016PASA...33...52F        (SIMBAD/NED BibCode)
    =2016yCat.5148....0F

Provenance

This table was originally ingested by the HEASARC in May 2017. It was updated in May 2023 to version "2.pre" based upon the data file downloaded from the author's website at https://quasars.org/morx.htm.

If using this catalog in published research, the author has requested that it be cited as MORX v2.pre, Flesch, E.W. 2023, website quasars.org.


Parameters

Name
The name of the object taken from the literature or created by the author. Previously nameless objects here are given J2000 position-based names, e.g., "MORX J000001.5-251706".

RA
The Right Ascension of the optical object in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 10-7 degrees in the original data. The author notes that these positions are too precise, but accommodate a minuscule round-up which prevents inadvertent truncation when converted to sexagesimal coordinates.

Dec
The Declination of the optical object in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 10-7 degrees in the original data. The author notes that these positions are too precise, but accommodate a minuscule round-up which prevents inadvertent truncation when converted to sexagesimal coordinates.

LII
The Galactic Longitude of the optical object. This parameter has been added by the HEASARC and is derived from the J2000.0 source position.

BII
The Galactic Latitude of the optical object. This parameter has been added by the HEASARC and is derived from the J2000.0 source position.

Broad_Type
This parameter contains information on the type classification of the object and its possible associations with radio and/or X-ray sources, or with double-lobed radio sources, as follows:

       A = AGN, type-I Seyferts/host-dominated
       B = BL Lac type object.  (FSRQs are typed as QSOs here)
       C = cataclysmic variable star
       G = galaxy
       K = NLQSO, type-II narrow-line core-dominated
       L = lensed quasar extra image
       N = NLAGN, type-II Seyferts/host-dominated, but could be NELGs, ELGs,
           LINERs, or unclear AGN (this is a catch-all category)
       Q = QSO, type-I broad-line core-dominated
       S = star classified although legacy stars are often without spectrum
       R = radio association displayed
       X = X-ray association displayed
       2 = double radio lobes displayed (declared by data-driven algorithm)
  

Rmag
The red optical magnitude of the object. The type and source of this magnitude is specified in the optical_flag parameter value. Optical data are from the APM (http://www.ast.cam.ac.uk/~mike/apmcat/), USNO-A & USNO-B (http://www.nofs.navy.mil/), and the SDSS (http://sdss3.org/). Magnitudes have been recalibrated from the original APM/USNO-A values (which are POSS-I or UKST identified in the description for the optical_flag parameter) as documented in QORG (2004, A&A, 427, 387). Calibrated USNO-A magnitudes are often retained in preference to USNO-B. APM galaxies brighter than 17th magnitude are usually represented as far too bright due to PSF modeling. If the optical_flag parameter value contains r/b/g/i/v/u/z, then the magnitudes are from the object's source catalog, e.g., SDSS, 2QZ, etc. Note that many SDSS magnitudes are extinction-"corrected" ~0.3 mag brighter than photometry.

Bmag
The blue optical magnitude of the object. The type and source of this magnitude is specified in the optical_flag parameter value. Optical data are from the APM (http://www.ast.cam.ac.uk/~mike/apmcat/), USNO-A & USNO-B (http://www.nofs.navy.mil/), and the SDSS (http://sdss3.org/). Magnitudes have been recalibrated from the original APM/USNO-A values (which are POSS-I or UKST identified in the description for the optical_flag parameter) as documented in QORG (2004, A&A, 427, 387). Calibrated USNO-A magnitudes are often retained in preference to USNO-B. APM galaxies brighter than 17th magnitude are usually represented as far too bright due to PSF modeling. If the optical_flag parameter value contains r/b/g/i/v/u/z, then the magnitudes are from the object's source catalog, e.g., SDSS, 2QZ, etc. Note that many SDSS magnitudes are extinction-"corrected" ~0.3 mag brighter than photometry.

Optical_Flags
This field contains coded information on the optical source properties, as follows:

       p = optical magnitudes are POSS-I O (violet 4050A) and E (red 6400A).
           These are preferred because O is well-offset from E, and those plates
           were always taken on the same night, thus the red-blue color is
           correct even for variable objects.  Epoch is 1950's.
       j = optical magnitudes are SERC J (Bj 4850A) and R (red 6400A) from the
           POSS-II or UKST surveys.  Red-blue color is less reliable because the
           red & blue plates were taken in different epochs, i.e., years apart.
       b = blue magnitude is Vega 4400A (Johnson), red is 6400A (Cousins).
       g = blue magnitude is SDSS-type green 4900A, red is r 6200A.
       n = blue magnitude is Pan-STARRS green 4900A, red is r 6200A.
       d = magnitudes are DES DR2 AB r & g.
       u = blue magnitude is SDSS ultraviolet 3850A.
       v = red magnitude is visual 5500A, or estimated from a sky chart/viewer.
       i = red magnitude is infrared 7500A.
       z = red magnitude is infrared z 8600A.
       r = red magnitude is r 6200A.
       (blank) = red alone is 6400A (Cousins); if both mags present = estimates.
       G = Gaia-DR2 astrometry shown, precessed to J2000 by CDS.  If 'G' is alone
           then the magnitudes are Gaia RP & BP, or Gaia G if red band only.
       N = Pan-STARRS astrometry shown.  If 'N' is alone, PS photometry also.
       D = DES DR2 astrometry shown.  If 'D' is alone, DES photometry also.
       + = variability nominally detected in both red/blue over multi-epoch data.
       m = proper motion detected.  If from Gaia-DR2/3 ('G' also present in this
           field), then this is proper motion or parallax which usually signifies
           a star, but optical centroids can deflect within the optical gradient
           of a near moving neighbor or if either object is variable; some will
           be quasars.  If not Gaia, it is from USNO-B which is nominal only.
       e = USNO-B1.0 "epoch 2000" projected location based on nominal proper
           motion, can miss true location by many arcsec.
       % = swap of two "unplugged" SDSS spectra which crossed wires.
       a = object is host-dominated with faint nuclear activity, such as an SDSS
           pipeline galaxy with an AGN subclass or AGN-classed elsewhere, see its
           citation.  Milliquas class is 'A' if BROADLINE, else 'N'.
  

Red_PSF_Flag
A coded representation for the point spread function (PSF) of the optical source in the red. The APM, USNO-B, and SDSS provide PSF class, albeit using different criteria. The codes are 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 = unseen / unclear in this band (fainter than plate depth, confused, etc.)
  

Blue_PSF_Flag
A coded representation for the point spread function (PSF) of the optical source in the blue. The APM, USNO-B, and SDSS provide PSF class, albeit using different criteria. The codes are 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 = unseen / unclear in this band (fainter than plate depth, confused, etc.)
  

Redshift
The redshift of the object, taken from the literature as specified in the ref_redshift parameter. Photometric redshifts are rounded here to 0.1z for objects classified as "q" (photometric quasars) and to 0.01z for "g" (photometric galaxies). If the cited reference is MORX, then it is a photometric redshift calculated as described in Appendix B of the HMQ paper (Flesch 2015, PASA, 32, 10).

Ref_Source
The reference code for the citation of the named object. The file https://quasars.org/MORX-references.txt lists all of the numerical reference codes given in this table in sequence. Each row in this file has 2 columns, the first being the citation number as it appears in the table and the second being the citation, i.e., the bibcode and authors list, and sometimes a brief description or website URL. These numerical reference codes are consistent with those used in the Half Million Quasars catalog (HMQ: 2015, CDS Cat. VII/273). The alphanumerical reference codes are the same as those used in the Million Quasars catalog (MILLIQUAS).

Ref_Redshift
The reference code for the cited redshift of the object. The file https://quasars.org/MORX-references.txt lists all of the numerical reference codes given in this table in sequence. Each row in this file has 2 columns, the first being the citation number as it appears in the table and the second being the citation, i.e., the bibcode and authors list, and sometimes a brief description or website URL. These numerical reference codes are consistent with those used in the Half Million Quasars catalog (HMQ: 2015, CDS Cat. VII/273). The alphanumerical reference codes are the same as those used in the Million Quasars catalog (MILLIQUAS).

Radio_Xray_Likelihood
The radio/X-ray (RX) association likelihood, in percent. These likelihoods are calculated from areal densities as described in the QORG (Flesch and Hardcastle 2004, A&A, 427, 387) and ARXA (Flesch 2010, PASA, 27, 283, CDS Cat. V/134) papers.

QSO_Prob
The calculated probability that the object is a QSO, in percent. These probabilities are derived from the radio/X-ray association(s) by counting fellow objects (of similar photometry and associations) which are already fully classified. Values are also displayed for those fully classified objects to show the performance.

Galaxy_Prob
The calculated probability that the object is a galaxy, in percent. These probabilities are derived from the radio/X-ray association(s) by counting fellow objects (of similar photometry and associations) which are already fully classified. Values are also displayed for those fully classified objects to show the performance.

Star_Prob
The calculated probability that the object is a star, in percent. These probabilities are derived from the radio/X-ray association(s) by counting fellow objects (of similar photometry and associations) which are already fully classified. Values are also displayed for those fully classified objects to show the performance.

Radio_Likelihood
The likelihood of the radio association with the optical object, in percent. These likelihoods are calculated from areal densities as described in the QORG (Flesch and Hardcastle 2004, A&A, 427, 387) and ARXA (Flesch 2010, PASA, 27, 283, CDS Cat. V/134) papers. These radio likelihoods are calculated independently of the X-ray likelihoods.

Xray_Likelihood
The likelihood of the X-ray association with the optical object, in percent. These likelihoods are calculated from areal densities as described in the QORG (Flesch and Hardcastle 2004, A&A, 427, 387) and ARXA (Flesch 2010, PASA, 27, 283, CDS Cat. V/134) papers. These X-ray likelihoods are calculated independently of the radio likelihoods.

CXO_Name
The Chandra X-ray source detection identification, if any.

XMM_Name
The XMM-Newton X-ray source identification, if any.

Swift_Name
The Swift X-ray source identification, if any.

ROSAT_or_XMMSlew_Name
The ROSAT or XMM-Slew X-ray source detection identification, if any.

VLASS_Name
The VLASS core radio source detection identification, if any.

FIRST_or_SUMSS_Name
The FIRST or SUMSS core radio source identification, if any.

LoTSS_Name
The LoTSS core radio source detection identification, if any.

RACS_Name
The RACS core radio source detection identification, if any.

NVSS_Name
The NVSS core radio source identification, if any.

Alt_Name_1
The first radio lobe identification, if any.

Alt_Name_2
The second radio lobe identification, if any.

Lobe_Extent
The sky extent of the longer lobe, in arcseconds.

Class
The HEASARC Browse object classification, based on the value of the broad_type parameter.


Contact Person

Questions regarding the MORX database table can be addressed to the HEASARC Help Desk.
Page Author: Browse Software Development Team
Last Modified: Tuesday, 16-May-2023 16:30:09 EDT