J/ApJ/923/75ivo://CDS.VizieR/J/ApJ/923/75doi:10.26093/cds/vizier.19230075CDSKerby S.Kaur A.Falcone A.D.Eskenasy R.Hancock F.Stroh M.C.,Ferrara E.C.Ray P.S.Kennea J.A.Grove E.2024-09-10T20:13:36Z2023-06-28T08:03:22ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frgamma-ray-astronomyx-ray-sourcesvisible-astronomybroad-band-photometryactive-galactic-nucleibl-lacertae-objectspulsarsThe Fermi-LAT unassociated sources represent some of the most enigmatic gamma-ray sources in the sky. Observations with the Swift-XRT and -UVOT telescopes have identified hundreds of likely X-ray and UV/optical counterparts in the uncertainty ellipses of the unassociated sources. In this work we present spectral fitting results for 205 possible X-ray/UV/optical counterparts to 4FGL unassociated targets. Assuming that the unassociated sources contain mostly pulsars and blazars, we develop a neural network classifier approach that applies gamma-ray, X-ray, and UV/optical spectral parameters to yield a descriptive classification of unassociated spectra into pulsars and blazars. From our primary sample of 174 Fermi sources with a single X-ray/UV/optical counterpart, we present 132 P_bzr_>0.99 likely blazars and 14 P_bzr_<0.01 likely pulsars, with 28 remaining ambiguous. These subsets of the unassociated sources suggest a systematic expansion to catalogs of gamma-ray pulsars and blazars. Compared to previous classification approaches our neural network classifier achieves significantly higher validation accuracy and returns more bifurcated Pbzr values, suggesting that multiwavelength analysis is a valuable tool for confident classification of Fermi unassociated sources.2021ApJ...923...75Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/923/75CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/swift : Swift Master Catalog (HEASARC, 2004-)IX/43 : 1SXPS Swift X-ray telescope point source catalogue (Evans+ 2014)IX/67 : Fermi LAT 4th source cat. (4FGL-DR3) (Fermi-LAT col., 2022)J/A+A/333/231 : O-M stars model atmospheres (Bessell+ 1998)J/A+A/551/A142 : 7yr Swift-XRT point source catalog (1SWXRT) (D'Elia+, 2013)J/ApJS/208/17 : 2nd Fermi LAT cat. of gamma-ray pulsars (2PC) (Abdo+, 2013)J/ApJS/209/9 : Unidentified gamma-ray sources. IV. X-ray (Paggi+, 2013)J/ApJ/810/14 : Third catalog of LAT-detected AGNs (3LAC) (Ackermann+, 2015)J/ApJ/820/8 : 3FGL sources statistical classifications (Saz Parkinson+, 2016)J/ApJ/854/99 : The Einstein@Home gamma-ray pulsar survey. II. (Wu+, 2018)J/ApJ/887/18 : Classif. of X-ray counterparts of 3FGL sources (Kaur+, 2019)J/ApJS/247/33 : The Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)J/AJ/161/154 : 3FGL X-ray Analysis and ML (Kerby+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/923/75https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/923/75http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/923/75https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/923/75https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/923/75http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/923/75GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/923/75/table3 (*Fermi-LAT features for the unassociated sample investigated in this work, along with Swift-XRT and -UVOT parameters for all possible X-ray/UV/optical counterparts (single counterpart))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/923/75/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/923/75/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/923/75/table3?GETtext/xml+votable180.050000true7.667083-23.47250.005555555555555556Cone search capability for table J/ApJ/923/75/table4 (*Fermi-LAT features for the unassociated sample investigated in this work, along with Swift-XRT and -UVOT parameters for all possible X-ray/UV/optical counterparts (multiple X-ray counterparts))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/923/75/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/923/75/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/923/75/table4?GETtext/xml+votable180.050000true21.55-67.7961110.0055555555555555566/50 760 836 973 1113 1153 1531 1538 2167 2324 3234 3721 3793 5193 5415 5800 6477 7092 7137 7237 7531 7743 7940 7958 8603 9321 9417 9642 9759 9914 10011 10468 11156 11964 12164 12668 12856 12923 13765 13986 14274 14462 14477 14608 14619 14856 15043 15362 16137 16182 16385 16541 16560 16650 16686 17270 17734 18626 19431 20221 20588 21010 21496 21710 21800 22341 22482 23427 23728 24004 24432 24554 24789 25142 25403 25512 25525 26553 26933 27080 27964 28172 28690 28772 28817 28837 29118 29151 29881 30259 30262 30473 30498 32379 32394 32420 32578 32742 32909 33087 33206 33270 33341 33482 33514 33596 33801 34053 34949 35343 35374 35395 35637 36128 36395 36445 37222 37338 37365-37366 37629 37744 37872 37884 38066 38092 38127 38130 38178 38194 38476 38488 38492 38511 38880 39114 39139 39257 39276 39431 39439 39459 39828 39998 40025 40113 40366 40808 41253 41359 41631 41655 41688 42087 42099 42169 42193 42224 42229 42379 42392 42397 42449 42989 43197 43634 43751 43856 44634 44751 44984 45077 45375 45754 45859 45970 45974 45998 46209 46239 46342 46444 46480 46622 47370 47460 48200 48896https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/923/75?format=asciiGamma-rayX-rayOpticalRadiodefaultJ/ApJ/923/75/table3*Fermi-LAT features for the unassociated sample investigated in this work, along with Swift-XRT and -UVOT parameters for all possible X-ray/UV/optical counterparts (single counterpart)4FGLTarget 4FGL identifier (JHHMM.m+DDMMc) (2)meta.id;meta.maincharlogFG[-12.1/-10.2] Log {gamma}-ray flux; erg/s/cm^2^log(1e-07W.cm**-2)phot.flux.density;em.gamma.hardfloatGammaG[1.25/3.01] The {gamma}-ray photon indexspect.indexfloatVarInd[1.23/59.61] Year-over-year {gamma}-ray variability indexmeta.code;src.var.indexfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTypeSource type code (1)meta.code.classcharCurvInd[0/14.3] The {gamma}-ray curvature indexspect.indexfloatSwXF4Target SwXF4 identifier (JHHMMSS.s+DDMMSS)meta.id.crosscharlogFX[-13.11/-7.39] Log X-ray 0.3-10keV flux; erg/s/cm^2^log(1e-07W.cm**-2)phot.flux;em.X-rayfloatGammaX[-1.6/10] X-ray photon indexspect.indexfloatUVOTSwift/UVOT filter usedmeta.code;instr.filtercharVmag[14.68/22.7] Apparent V band Vega magnitude (G1)magphot.mag;em.opt.VfloatSimbadSimbad column added by the CDSmeta.ref.urlchar_RAPositions from X-ray source name (SwXF4) (right ascension part)degpos.eq.ra;meta.main_DEPositions from X-ray source name (SwXF4) (declination part)degpos.eq.dec;meta.mainPbzr[0.0015/1] The blazar probabilitystat.fit.goodnessfloatJ/ApJ/923/75/table4*Fermi-LAT features for the unassociated sample investigated in this work, along with Swift-XRT and -UVOT parameters for all possible X-ray/UV/optical counterparts (multiple X-ray counterparts)UVOTSwift/UVOT filter usedmeta.code;instr.filtercharVmag[13.37/21.7] Apparent V band Vega magnitude (G1)magphot.mag;em.opt.VfloatPbzr[0.0015/1] The blazar probabilitystat.fit.goodnessfloatSimbadSimbad column added by the CDSmeta.ref.urlchar_RAPositions from X-ray source name (SwXF4) (right ascension part)degpos.eq.ra;meta.main_DEPositions from X-ray source name (SwXF4) (declination part)degpos.eq.dec;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint4FGLTarget 4FGL identifier (JHHMM.m+DDMM)meta.id;meta.maincharm_4FGLNumber of X-ray possible counterparts to the Fermi sourcemeta.numberintnullablelogFG[-12.1/-10.47] Log {gamma}-ray flux; erg/s/cm^2^log(1e-07W.cm**-2)phot.flux.density;em.gamma.hardfloatGammaG[1.7/2.71] The {gamma}-ray photon indexspect.indexfloatVarInd[1.65/27.2] Year-over-year {gamma}-ray variability indexmeta.code;src.var.indexfloatCurvInd[0.05/10.7] The {gamma}-ray curvature indexspect.indexfloatSwXF4Target SwXF4 identifier (JHHMMSS.s+DDMMSS)meta.id.crosscharf_SwXF4[*] Flag on SwXF4 (1)meta.codecharlogFX[-14.1/-8.97] Log X-ray 0.3-10keV flux; erg/s/cm^2^log(1e-07W.cm**-2)phot.flux;em.X-rayfloatGammaX[0.01/7.9] X-ray photon indexspect.indexfloat