J/ApJ/782/41ivo://CDS.VizieR/J/ApJ/782/41doi:10.26093/cds/vizier.17820041CDSDoert M.Errando M.2018-01-04T08:23:08Z2016-01-28T14:20:30ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleigamma-ray-astronomyThe second Fermi-LAT source catalog (2FGL) is the deepest all-sky survey available in the gamma-ray band. It contains 1873 sources, of which 576 remain unassociated. Machine-learning algorithms can be trained on the gamma-ray properties of known active galactic nuclei (AGNs) to find objects with AGN-like properties in the unassociated sample. This analysis finds 231 high-confidence AGN candidates, with increased robustness provided by intersecting two complementary algorithms. A method to estimate the performance of the classification algorithm is also presented, that takes into account the differences between associated and unassociated gamma-ray sources. Follow-up observations targeting AGN candidates, or studies of multiwavelength archival data, will reduce the number of unassociated gamma-ray sources and contribute to a more complete characterization of the population of gamma-ray emitting AGNs.2014ApJ...782...41Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/782/41CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/209/9 : Unidentified gamma-ray sources. IV. X-ray (Paggi+, 2013)J/ApJS/208/17 : 2nd Fermi LAT cat. of gamma-ray pulsars (2PC) (Abdo+, 2013)J/ApJS/206/13 : Blazars with {gamma}-ray counterparts. II. (Massaro+, 2013)J/ApJ/779/133 : X-ray & radio fluxes of unassociated 2FGL sourcesJ/MNRAS/424/L64 : AGN/pulsar distinction for 2FGL sources (Mirabal+, 2012)J/ApJS/199/31 : Fermi LAT second source catalog (2FGL) (Nolan+, 2012)J/ApJS/188/405 : Fermi-LAT first source catalog (1FGL) (Abdo+, 2010)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/782/41https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/782/41http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/782/41https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/782/41https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/782/41http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/782/41GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/782/41/table3 (List of high-confidence AGN candidates, ordered by R.A.)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/782/41/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/782/41/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/782/41/table3?GETtext/xml+votable180.050000true1.05622.1370.0055555555555555566/172 189 289 428 720 731 1609 1964 3099 3130 3207 3278 3306 3340 3465 3652 3700 4088 4480 4762 5010 5352 5448 6062 6292 7131 7405 7911 7936 8302 8474 9175 9417 9647 9855 10096 11290 11457 12164 12207 12277 12410 12490 12782 13275 13278 13279 13733 14704 14738 14906 15397 15468 15669 15783 15996 17154 17366 17819 18343 18366 19525 19589 20230 20481 20606 21164 21438 21593 21647 21710 21806 21898 22239 22683 22849 23105 23338 23364 24272 24307 24482 24566 24798 24836 24885 25234 25468 25781 25820 26892 26897 28821 28839 28856 28859 28904 29109 29185 29213 29547 29647 29771 29835 30743 30827 30836 30968 30995 31011 31111 31199 31221 31262 31575 31778 31788 31837 31860 31976 32035 32050 32288 32739 33030 33059 33198 33464 33506 33528 34107 34128 34375 34569 34593 34968 35063 35227 36144 36615 36716 36886 36910 37222 37479 37487 37850 37928 37991 38018 38112 38488 38633 38911 39978 40143 40422 40680 41110 41460 41543 41571 41584 41654 41692 41735 41740 41770 42005 42136 42157 42189 42193 42212 42220 42335 42565 42585 42596 42853 43075 43077 43109 43156 43225 43280 43319 43435 43643 43824 43848 43879 43891 43996 44011 44253 44284 44585 44654 45011 45199 45284 45316 45397 45446 45586 45618 45914 46035 46285 46337 46361 46534 46568 46569 46613 46721 47154 47442 47461 47606 47894 47939 48019 48528 48575 48685 48743 48773 48957https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/782/41?format=asciiGamma-raydefaultJ/ApJ/782/41/table3List of high-confidence AGN candidates, ordered by R.A.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint2FGLIdentifier in the second Fermi-LAT source (2FGL) catalog (Nolan et al. 2012, cat. J/ApJS/199/31) (JHHMM.s+DDMM or JHHMM.s+DDMMc format)meta.id;meta.maincharRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainLRF[0.86/1] Random forest likelihood L_RF_ (1)stat.likelihoodfloatLNN[0.92/1] Neural network likelihood L_NN_ (1)stat.likelihoodfloatCl[AU] Class predicted by Mirabal et al. 2012 (cat. J/MNRAS/424/L64) (A=Active Galactic Nucleus (AGN), U=Uncertain, NULL=Not present)src.classcharC1[a] Infrared counterpart in Massaro et al. 2013 (cat. J/ApJS/206/13)meta.id.assoccharC2[b] X-ray counterpart in Paggi et al. 2013 (cat. J/ApJS/209/9)meta.id.assoccharC3[c] AGN candidate in Acero et al. 2013 (cat. J/ApJ/779/133)meta.id.assoccharSimbadSimbad column added by the CDSmeta.ref.urlcharNEDSimbad column added by the CDSmeta.ref.urlchar