J/A+A/370/931ivo://CDS.VizieR/J/A+A/370/931doi:10.26093/cds/vizier.33700931CDSPiatti A.E.Claria J.J.2007-07-31T13:40:42Z2007-07-31T13:37:44ZCDS support team

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

cds-question@unistra.fropen-star-clustersccd-photometryinfrared-photometryvisible-astronomybroad-band-photometryCCD observations in the B, V and I passbands have been used to generate colour-magnitude diagrams reaching down to V~19mag for two slightly characterized (Melotte 105 and Hogg 15) and two almost unstudied (Pismis 21 and Ruprecht 140) open clusters. The sample consists of about 1300 stars observed in fields of about 4'x4'. Our analysis shows that neither Pismis 21 nor Ruprecht 140 are genuine open clusters since no clear main sequences or other meaningful features can be seen in their colour-magnitude diagrams. Melotte 105 and Hogg 15 are open clusters affected by E(B-V)=0.42+/-0.03 and 0.95+/-0.05, respectively. Their distances to the Sun have been estimated as 2.2+/-0.3 and 2.6+/-0.08kpc, respectively, while the corresponding ages estimated from empirical isochrones fitted to the Main Sequence cluster members are ~350Myr and 300Myr, respectively. The present data are not consistent with the membership of the WN6 star HDE 311884 to Hogg 15.2001A&A...370..931Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/370/931CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/360/529 : Pismis 22, NGC 6178, NGC 6216, Ruprecht 130 (Piatti+, 2000)J/ApJS/116/263 : VI photometry of open clusters (Piatti+ 1998)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/370/931https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/370/931http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/370/931https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/370/931https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/370/931http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/370/931GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/370/931/table2 (Magnitudes and colours of stars in the field of Melotte 105)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/370/931/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/370/931/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/370/931/table2?GETtext/xml+votable180.050000true169.9874525-63.48795140.005555555555555556Cone search capability for table J/A+A/370/931/table3 (Magnitudes and colours of stars in the field of Hogg 15.)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/370/931/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/370/931/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/370/931/table3?GETtext/xml+votable180.050000true190.956271-63.1463810.005555555555555556Cone search capability for table J/A+A/370/931/table4 (Magnitudes and colours of stars in the field of Pismis 21.)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/370/931/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/370/931/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/370/931/table4?GETtext/xml+votable180.050000true229.256809-59.6787840.005555555555555556Cone search capability for table J/A+A/370/931/table5 (Magnitudes and colours of stars in the field of Ruprecht 140.)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/370/931/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/370/931/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/370/931/table5?GETtext/xml+votable180.050000true275.5006469-33.19321750.0055555555555555566/28739 37215 37237 41658 41756 43024https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/370/931?format=asciiOpticalInfrareddefaultJ/A+A/370/931/table2Magnitudes and colours of stars in the field of Melotte 105recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar numbermeta.idintXposX coordinate (1)pixpos.cartesian.x;instr.detfloatYposY coordinate (1)pixpos.cartesian.y;instr.detfloatVmagV magnitudemagphot.mag;em.opt.Vfloate_Vmagrms uncertainty on Vmagmagstat.error;phot.mag;em.opt.VfloatB-V? B-V colour indexmagphot.color;em.opt.B;em.opt.Vfloatnullablee_B-V? rms uncertainty on B-Vmagstat.error;phot.color;em.opt.BfloatnullableV-IV-I colour indexmagphot.color;em.opt.V;em.opt.Ifloate_V-Irms uncertainty on V-Imagstat.error;phot.color;em.opt.Vfloato_VmagNumber of measurementsmeta.numberint_RAJ2000 Positions computed from (Xpos,Ypos) by VizieR (right ascension part)degpos.eq.ra;meta.main_DEJ2000 Positions computed from (Xpos,Ypos) by VizieR (declination part)degpos.eq.dec;meta.mainJ/A+A/370/931/table3Magnitudes and colours of stars in the field of Hogg 15.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar numbermeta.idintXposX coordinate (1)pixpos.cartesian.x;instr.detfloatYposY coordinate (1)pixpos.cartesian.y;instr.detfloatVmagV magnitudemagphot.mag;em.opt.Vfloate_Vmagrms uncertainty on Vmagmagstat.error;phot.mag;em.opt.VfloatB-V? B-V colour indexmagphot.color;em.opt.B;em.opt.Vfloatnullablee_B-V? rms uncertainty on B-Vmagstat.error;phot.color;em.opt.BfloatnullableV-IV-I colour indexmagphot.color;em.opt.V;em.opt.Ifloate_V-Irms uncertainty on V-Imagstat.error;phot.color;em.opt.Vfloato_VmagNumber of measurementsmeta.numberint_RAJ2000 Positions computed from (Xpos,Ypos) by VizieR (right ascension part)degpos.eq.ra;meta.main_DEJ2000 Positions computed from (Xpos,Ypos) by VizieR (declination part)degpos.eq.dec;meta.mainJ/A+A/370/931/table4Magnitudes and colours of stars in the field of Pismis 21.VmagV magnitudemagphot.mag;em.opt.VfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar numbermeta.idintXposX coordinate (1)pixpos.cartesian.x;instr.detfloatYposY coordinate (1)pixpos.cartesian.y;instr.detfloate_Vmagrms uncertainty on Vmagmagstat.error;phot.mag;em.opt.VfloatB-V? B-V colour indexmagphot.color;em.opt.B;em.opt.Vfloatnullablee_B-V? rms uncertainty on B-Vmagstat.error;phot.color;em.opt.BfloatnullableV-IV-I colour indexmagphot.color;em.opt.V;em.opt.Ifloate_V-Irms uncertainty on V-Imagstat.error;phot.color;em.opt.Vfloato_VmagNumber of measurementsmeta.numberint_RAJ2000 Positions computed from (Xpos,Ypos) by VizieR (right ascension part)degpos.eq.ra;meta.main_DEJ2000 Positions computed from (Xpos,Ypos) by VizieR (declination part)degpos.eq.dec;meta.mainJ/A+A/370/931/table5Magnitudes and colours of stars in the field of Ruprecht 140.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar numbermeta.idintXposX coordinate (1)pixpos.cartesian.x;instr.detfloatYposY coordinate (1)pixpos.cartesian.y;instr.detfloatVmagV magnitudemagphot.mag;em.opt.Vfloate_Vmagrms uncertainty on Vmagmagstat.error;phot.mag;em.opt.VfloatB-V? B-V colour indexmagphot.color;em.opt.B;em.opt.Vfloatnullablee_B-V? rms uncertainty on B-Vmagstat.error;phot.color;em.opt.BfloatnullableV-IV-I colour indexmagphot.color;em.opt.V;em.opt.Ifloate_V-Irms uncertainty on V-Imagstat.error;phot.color;em.opt.Vfloato_VmagNumber of measurementsmeta.numberint_RAComputed Right Ascension for Equinox: J2000degpos.eq.ra;meta.main_DEComputed Declination for Equinox: J2000degpos.eq.dec;meta.main