J/AJ/152/192ivo://CDS.VizieR/J/AJ/152/192doi:10.26093/cds/vizier.51520192CDSAnthony-Twarog B.J.Deliyannis C.P.Twarog B.A.2017-03-13T14:06:24Z2017-02-10T15:43:59ZCDS support team

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

cds-question@unistra.fropen-star-clustersccd-photometryvisible-astronomymedium-band-photometrynarrow-band-photometryPrecision uvbyCaH{beta} photometry of the metal-deficient, old open cluster NGC2506 is presented. The survey covers an area of 20'*20' and extends to V~18 for b-y and H{beta} and to V~17.0 for c_1_ and hk. For V brighter than 16.0, photometric scatter among the indices leads to the recovery of six known variables within the cluster core and five new variables in the outer 5' of the survey field. Proper motions, radial velocities, and precise multicolor indices are used to isolate a highly probable sample of cluster members from the very rich color-magnitude diagram. From 257 highly probable members at the cluster turnoff, we derive a reddening estimate of E(b-y)=0.042+/-0.001 (E(B-V)=0.058+/-0.001), where the errors refer to the internal standard errors of the mean. [Fe/H] is derived from the A/F dwarf members using both m_1_ and hk, leading to [Fe/H]=-0.296+/-0.011 (sem) and -0.317+/-0.004 (sem), respectively. The weighted average, heavily dominated by hk, is [Fe/H]=-0.316+/-0.033. Based on red giant members, we place an upper limit of +/-0.010 on the variation in the reddening across the face of the cluster. We also identify two dozen potential red giant cluster members outside the cluster core. Victoria-Regina isochrones on the Stromgren system produce an excellent match to the cluster for an apparent modulus of (m-M)=12.75+/-0.1 and an age of 1.85+/-0.05Gyr.2016AJ....152..192Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/152/192CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2015)II/215 : uvby-beta Catalogue (Hauck+ 1997)J/A+A/585/A150 : On the metallicity of open clusters. III. (Netopil+, 2016)J/AJ/150/134 : uvbyCaH{beta} photometry of NGC 752 (Twarog+, 2015)J/AJ/148/51 : WIYN Open Cluster. LXI. NGC 6819 (Anthony-Twarog+, 2014)J/MNRAS/419/1350 : Red giants abundances in 4 open clusters (Reddy+, 2012)J/AJ/139/2034 : NGC 6253 stars equivalent widths (Anthony-Twarog+, 2010)J/A+A/485/303 : RVs for 1309 stars and 166 OCl (Mermilliod+, 2008)J/A+A/465/965 : BI light curve of NGC 2506 variables (Arentoft+, 2007)J/AJ/131/461 : Stromgren photometry of NGC 2420 (Anthony-Twarog+, 2006)J/A+A/438/1163 : Catalogue of Open Cluster Data (COCD) (Kharchenko+, 2005)J/AJ/129/872 : Stromgren photometry of NGC 2243 (Anthony-Twarog+, 2005)J/AJ/127/1000 : Stromgren photometry of NGC 3680 (Anthony-Twarog+, 2004)J/AJ/125/1383 : Stromgren photometry of NGC 6253 (Anthony-Twarog+, 2003)J/AJ/119/2282 : Stromgren photometry of IC 4651 (Anthony-Twarog+, 2000)J/AJ/109/2828 : CaII H and K filter photometry II. (Twarog+ 1995)http://webda.physics.muni.cz/ : WEBDA databasehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/152/192https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/152/192http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/152/192https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/152/192https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/152/192http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/152/192GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/152/192/table2 (Stromgren photometry in NGC 2506)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/152/192/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/152/192/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/152/192/table2?GETtext/xml+votable180.050000true120.12492389-10.799913890.0055555555555555566/21586https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/152/192?format=asciiOpticaldefaultJ/AJ/152/192/table2Stromgren photometry in NGC 2506Hb[2.37/9.51]? The H{beta} indexmagspect.index;em.line.Hbetafloatnullableb-y[0.013/1.221] The Stromgren (b-y) color indexmagphot.color;em.opt.B;em.opt.VfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintXpos[-552.35/656.22] WEBDA X pixel coordinatepixpos.cartesian.xfloatYpos[-615.61/637.53] WEBDA Y pixel coordinatepixpos.cartesian.yfloatRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainWEBDA[1101/5387]? WEBDA identification numbermeta.id;meta.mainintnullableMm[0/1]? Membership probability (1)stat.probabilityfloatnullableVmag[10.76/18] The V-band magnitudemagphot.mag;em.opt.Vfloate_Vmag[0/0.092] The 1{sigma} uncertainty in Vmagmagstat.error;phot.mag;em.opt.Vfloate_b-y[0.001/0.12] The 1{sigma} uncertainty in b-ymagstat.error;phot.color;em.opt.Bfloatm1[-0.165/0.867]? The Stromgren metallicity index m_1_=(v-b)-(b-y)magphot.colorfloatnullablee_m1[0.002/0.29]? The 1{sigma} uncertainty in m1magstat.errorfloatnullablec1[-0.177/1.21]? The Stromgren discontinuity index c_1_=(u-v)-(v-b)magphot.colorfloatnullablee_c1[0.002/0.4]? The 1{sigma} uncertainty in c1magstat.errorfloatnullablehk[-0.053/1.937]? The Stromgren hk indexmagphot.colorfloatnullablee_hk[0.002/0.25]? The 1{sigma} uncertainty in hkmagstat.errorfloatnullablee_Hb[0.001/0.19]? The 1{sigma} uncertainty in Hbmagstat.errorfloatnullableClassCalibration classification (B, BV, D, DV, G, or GV) (2)meta.code.classcharNy[2/23] Number of y filter observationsmeta.numberintNb[2/14] Number of b filter observationsmeta.numberintNv[0/9] Number of v filter observationsmeta.numberintNu[0/14] Number of u filter observationsmeta.numberintNCa[0/14] Number of Ca filter observationsmeta.numberintNn[0/8] Number of H{beta} narrow filter observationsmeta.numberintNw[0/8] Number of H{beta} wide filter observationsmeta.numberint