J/MNRAS/274/1107ivo://CDS.VizieR/J/MNRAS/274/1107doi:10.26093/cds/vizier.72741107CDSNaim A.Lahav O.Buta R.J.Corwin H.G.Jr.De Vaucouleurs G.,Dressler A.Huchra J.P.Van Den Bergh S.Raychaudhury S.Sodre L.Jr,Storrie-Lombardi M.C.2024-06-24T20:14:30Z2000-04-10T21:10:08ZCDS support team

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

cds-question@unistra.frgalaxiescatalogsgalaxy-classification-systemsWe investigate the consistency of visual morphological classifications of galaxies by comparing classifications for 831 galaxies from six independent observers. The galaxies were classified on laser print copy images or on computer screen using scans made with the Automated Plate Measuring (APM) machine. Classifications are compared using the Revised Hubble numerical type index T. We find that individual observers agree with one another with rms combined dispersions of between 1.3 and 2.3 type units, typically about 1.8 units. The dispersions tend to decrease slightly with increasing angular diameter and, in some cases, with increasing axial ratio (b/a). The agreement between independent observers is reasonably good but the scatter is non-negligible. In spite of the scatter, the Revised Hubble T system can be used to train an automated galaxy classifier, e.g. an artificial neural network, to handle the large number of galaxy images that are being compiled in the APM and other surveys.1995MNRAS.274.1107Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/274/1107CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/155 : Third Reference Cat. of Bright Galaxies (RC3) (de Vaucouleurs+ 1991)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/274/1107https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/274/1107http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/274/1107https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/274/1107https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/274/1107http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/274/1107GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/274/1107/experts (Unified table of T-type classifications and mean types)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/274/1107/experts?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/274/1107/experts?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/274/1107/experts?GETtext/xml+votable180.050000true137.864592-14.81680.0055555555555555565/6237 6262-6263 6269 6354 6374 6434 6440 6442-6443 6500 6681 6/21781 21783 21824 21833 24925 24941-24942 24952-24953 24957-24958 25029 25036 25041-25044 25046-25047 25069 25075 25080-25081 25087 25201 25203 25205 25207 25209 25211 25214 25247 25262-25263 25270 25273 25275 25277 25281-25282 25300 25303 25308-25310 25312 25314 25319-25320 25322 25328 25333 25346-25347 25350 25355 25360 25362 25368-25369 25372-25373 25375 25380 25383 25385 25389 25393-25395 25399-25401 25403 25409 25411 25414-25415 25427 25437-25439 25444 25452 25460 25464-25465 25474-25476 25483 25485 25488 25490-25491 25495 25508 25511-25512 25514 25518 25520-25521 25523 25527 25533-25534 25540 25544 25547 25552 25562 25565 25569 25571-25572 25575 25581-25583 25590 25593 25595 25597-25599 25605 25610 25613 25615 25620 25624 25632 25634-25635 25640 25645 25647 25650 25653 25655-25657 25660 25662-25663 25668 25685 25696 25704-25705 25707 25710-25711 25715 25720-25721 25725-25726 25729 25731-25732 25734 25742 25746 25756 25764 25766-25767 25778-25779 25782 25784-25785 25788 25790-25791 25793 25809 25811 25816 25818 25827 25835 25841-25842 25846-25847 25850 25852-25853 25869 25874 25882-25883 25887-25889 25893 25898 25901 25907 25912 25918 25924 25989 25992 25996-25997 26025 26035 26037 26112-26113 26115-26117 26119 26121 26125 26127-26129 26132-26134 26136 26138-26139 26141-26142 26147-26148 26150 26157 26161 26166 26168-26169 26171 26173-26175 26178 26181-26182 26185 26187 26189 26191 26198 26202 26208 26213-26214 26217 26220 26222-26223 26225 26227 26230 26234 26240-26241 26244 26247 26259-26261 26263-26264 26267-26268 26285 26287 26290 26297 26304 26306-26309 26312 26314 26369 26372 26377 26627 26638 26651 26656 26660 26664 26667 26677 26691 26697 26703 26705 26707 26709 26713 26719 26721 26730 26732-26734 26739 26758 26764 26795-26796 26799 26803 26808 26810-26812 26814-26815 26817 26851-26852 26854 26862 26867 26869 26871-26873 26881 26884 26894 26915 26923 26930 26932 26934 26945 26955 26978 26983-26984 26988 26991 27008 27010 27019 27023 27031 27043 27049 27064 27137-27138 27141 27143 27145 27149-27151 27160 27167 27171 27173 27182 27184 27186 27208-27209 27224 27227 27245-27246 27279 27300-27301 27306 27314-27315 27333 27396 27650 27652 27654 31243-31245 31273 31279 31284 31360 31365 31369 40287 40307-40308 40310 40316 40373 40375-40377 40379-40381 40387 40398 40402 40404 40410-40412 40416 40418 40424-40425 40430 40436 40438 40442 40447 40543 40722-40723 40728 40736 40772 40774-40775 40777 40784-40785 40789 40791 40794 40798-40799 40803 40807 40818-40819 40822 40824 40827 40834 40837 40841 40848 40861 40863 40880 40893 40895 40898-40899 40903 40910 40917 40923 40933 40938-40939 40943 40946 40952-40954 44461 44470 44472 44475 44523 44637-44639 44660 44738 44741 44744 44761-44762 44766 44771 44774 44808-44809 44812 44815 44817 44822-44823 44826 44833 44835 44843-44844 44846 44848-44849 44852 44861 44864 44866 44868-44869 44892-44893 44896 44898 44904 44907 44915 44921-44922 44932-44933 44936 44945 44947 44955 44978 44984 44987 44995 44998 45002 45004 45030 45036-45037 45041https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/274/1107?format=asciiOpticaldefaultJ/MNRAS/274/1107/expertsUnified table of T-type classifications and mean typesGalIDGalaxy identificationcharprimaryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.intRA1950Right ascension (1950)DE1950Declination (1950)DiamDiameterarcminfloatRC3? RC3 (Cat. <VII/155>) T-type classification (1)floatnullableRB? R. Buta classification (1)intnullableHC? H. Corwin classification (1)intnullableGV? G. de Vaucouleurs classification (1)floatnullableAD? A. Dressler classification (1)intnullableJH? J. Huchra classification (1)intnullablevdB? ? S. van den Bergh classification (1)intnullableTs? Straight-mean type (1)floatnullableTw? Weighted-mean type (1)floatnullableNamesOther IdscharJ/MNRAS/274/1107/gdevaucG. de Vaucouleurs full classificationrecnoRecord number assigned by the VizieR team. Should Not be used for identification.intGalIDGalaxy identificationcharprimaryClassFull classificationcharJ/MNRAS/274/1107/hcorwinH. Corwin full classificationClassFull classificationcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.intGalIDGalaxy identificationcharprimaryJ/MNRAS/274/1107/svdberghS. van den Bergh full classificationrecnoRecord number assigned by the VizieR team. Should Not be used for identification.intGalIDGalaxy identificationcharprimaryClassFull classificationcharJ/MNRAS/274/1107/jhuchraJ. Huchra full classificationrecnoRecord number assigned by the VizieR team. Should Not be used for identification.intGalIDGalaxy identificationcharprimaryNGC? NGC number of the galaxyintnullableClassFull classificationcharJ/MNRAS/274/1107/rbutaR. Buta full classificationComCommentscharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.intGalGalaxy identificationcharClassFull classificationcharTypeT-type classificationintu_Type[: ?] Uncertainty flag on Typechar