J/AJ/146/57ivo://CDS.VizieR/J/AJ/146/57doi:10.26093/cds/vizier.51460057CDSContreras Pena C.Catelan M.Grundahl F.Stephens A.W.Smith H.A.2022-07-29T13:53:08Z2014-07-03T08:46:30ZCDS support team

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

cds-question@unistra.frglobular-star-clustersvisible-astronomybroad-band-photometryvariable-starsWe present BV photometry of the Galactic globular cluster NGC 6402 (M14), based on 65 V frames and 67 B frames, reaching two magnitudes below the turnoff level. This represents, to the best of our knowledge, the deepest color-magnitude diagram (CMD) of NGC 6402 available in the literature. Statistical decontamination of field stars as well as differential reddening corrections are performed in order to derive a precise ridgeline and hence physical parameters of the cluster. We discuss previous attempts at deriving a reddening value for the cluster, and argue in favor of a value E(B-V)=0.57+/-0.02, which is significantly higher than indicated by either the Burstein & Heiles or Schlegel et al. (corrected according to Bonifacio et al.) interstellar dust maps. Differential reddening across the face of the cluster, which we find to be present at the level of {Delta}E(B-V){approx}0.17mag, is taken into account in our analysis. We measure several metallicity indicators based on the position of the red giant branch (RGB) in the cluster CMD. These give a metallicity of [Fe/H]=-1.38+/-0.07 on the Zinn & West scale and [Fe/H]=-1.28+/-0.08 on the new Carretta et al. (UVES) scale. We also provide measurements of other important photometric parameters for this cluster, including the position of the RGB luminosity function "bump" and the horizontal branch morphology. We compare the NGC 6402 ridgeline with that of NGC 5904 (M5) derived by Sandquist et al., and find evidence that NGC 6402 and M5 have approximately the same age to within the uncertainties, although the possibility that M14 may be slightly older cannot be ruled out.2013AJ....146...57Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/146/57CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/140/1766 : RR Lyrae in M62 (NGC6266) (Contreras+, 2010)J/AJ/139/357 : Variable stars in NGC 5286 (Zorotovic+, 2010)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/146/57https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/146/57http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/146/57https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/146/57https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/146/57http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/146/57GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/146/57/table1 (BV photometry for M14)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/146/57/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/146/57/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/146/57/table1?GETtext/xml+votable180.050000true264.3096667-3.19455830.0055555555555555566/310433.322582951404819e-19 4.920466254354166e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/146/57?format=asciiOpticaldefaultJ/AJ/146/57/table1BV photometry for M14Star[1/8126] Running star number <[CCG2013] ID-NNNN> in Simbadmeta.id;meta.mainintprimaryRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainBmag[14.2/23.5] The B band magnitudemagphot.mag;em.opt.Bfloate_Bmag[0.001/0.06] Error in Bmagmagstat.error;phot.magfloatVmag[13.26/22.51] The V band magnitudemagphot.mag;em.opt.Vfloate_Vmag[0.001/0.06] Error in Vmagmagstat.error;phot.magfloatE(B-V)[-0.08/0.12] Differential reddening {Delta}E(B-V)magphot.color.excessfloat