J/A+A/402/801ivo://CDS.VizieR/J/A+A/402/801doi:10.26093/cds/vizier.34020801CDSLoup C.Delmotte N.Egret D.Cioni M.-R.Genova F.2008-10-04T21:46:24Z2008-10-04T21:42:49ZCDS support team

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

cds-question@unistra.frsurveyscarbon-starsmagellanic-cloudsastronomical-object-identificationWe have been recently faced with the problem of cross-identifying stars recorded in historical catalogues with those extracted from recent fully digitized surveys (such as DENIS and 2MASS). Positions mentioned in the old catalogues are frequently of poor precision, but are generally accompanied by finding charts where the interesting objects are flagged. Those finding charts are sometimes our only link with the accumulated knowledge of past literature. While checking the identification of some of these objects in several catalogues, we had the surprise to discover a number of discrepancies in recent works.The main reason for these discrepancies was generally the blind application of the smallest difference in position as the criterion to identify sources from one historical catalogue to those in more recent surveys. In this paper we give examples of such mis-identifications, and show how we were able to find and correct them.We present modern procedures to discover and solve cross-identification problems, such as loading digitized images of the sky through the Aladin service at CDS, and overlaying entries from historical catalogues and modern surveys. We conclude that the use of good finding charts still remains the ultimate (though time-consuming) tool to ascertain cross-identifications in difficult cases.2003A&A...402..801Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/402/801CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/228 : DENIS Catalogue toward Magellanic Clouds (DCMC) (Cioni+ 2000)J/A+A/369/932 : RI photometry of LMC carbon stars (Kontizas+, 2001)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/402/801https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/402/801http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/402/801https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/402/801https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/402/801http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/402/801GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/402/801/table2 (List of cross-identifications between the Blanco & McCarthy (1990AJ....100..674B), Kontizas et al. (2001, J/A+A/369/932), and DCMC (Cioni et al., 2000, II/228), catalogues)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/402/801/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/402/801/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/402/801/table2?GETtext/xml+votable180.050000true69.1868333-70.58330560.0055555555555555565/8263 8269 8272 8274-8275 8280 6/19456 33044 33046-33047 33049 33051 33060-33061 33080 33084-33085 33092 33094-33095 33106-33108 33112-33114 33124-33125 33127-33128 33136-33137 33792-33793 37410 37504 37506 37514-37515 37536-37537https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/402/801?format=asciiOpticaldefaultJ/A+A/402/801/table2List of cross-identifications between the Blanco & McCarthy (1990AJ....100..674B), Kontizas et al. (2001, J/A+A/369/932), and DCMC (Cioni et al., 2000, II/228), cataloguesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLMC-BMLMC-BM number (fieldnumber-sourcenumber)meta.id;meta.maincharKDMKActual [KDM2001] number: cross-identifications based on finding chartsmeta.idintDistDistance between LMC-BM and [KDM2001] positionsarcsecpos.angDistancefloatKDMK2? [KDM2001] number based on an automatic match with a radius of 30"meta.idintnullableDist2Distance between LMC-BM and [KDM2001]2 positionsarcsecpos.angDistancefloatKDMK3? [KDM2001] number based on an automatic match with a radius of 1'meta.idintnullableDist3Distance between LMC-BM and [KDM2001]3 positionsarcsecpos.angDistancefloatKDMK4? [KDM2001] number according to Kontizas et al. (J/A+A/369/932) Table 3meta.idintnullableDist4Distance between LMC-BM and [KDM2001]4 positionsarcsecpos.angDistancefloatDCMCDCMC J identification (HHMMSS.ss+DDMMSS.s): cross-identifications based on finding chartsmeta.idcharDCMC2Double entries in the DCMC cataloguemeta.idcharDENISDENIS data of nearby star(s)meta.ref.urlchar_RAPosition (from DCMC name) (right ascension part)degpos.eq.ra;meta.main_DEPosition (from DCMC name) (declination part)degpos.eq.dec;meta.mainJ/A+A/402/801/table1Cross-identification countsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFieldLMC-BM field number (1990AJ....100..674B)meta.id;obs.fieldintNC*Number of BM C stars (All = 849)meta.numberintNKDMNumber cross-identified with KDM , Kontizas et al., 2001, Cat. J/A+A/369/932) using finding charts (All = 586)meta.numberintNKDM3Number cross-identified in KDM Table 3 (All = 527)meta.numberintNwciNumber of wrong cross-identifications in KDM (All = 23)meta.numberintNmciNumber of missed cross-identifications in KDM (All = 67)meta.numberint