J/MNRAS/515/1469ivo://CDS.VizieR/J/MNRAS/515/1469doi:10.26093/cds/vizier/bg-g3-1dxCDSJohnson C.I.Rich R.M.Simion I.T.Young M.D.Clarkson W.I.,Pilachowski C.A.Michael S.Marchetti T.Soto M.Kunder A.,Koch-Hansen A.J.Vivas A.K.Joyce M.Shen J.Osmond A.2026-08-03T07:31:35Z2025-09-16T15:28:29ZCDS support team

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

cds-question@unistra.frmilky-way-galaxygiant-starsstandard-starsgalactic-centerastrometryphotometryvisible-astronomyextinctionstellar-distancemetallicityWe present photometric metallicity measurements for a sample of 2.6 million bulge red clump stars extracted from the Blanco DECam Bulge Survey (BDBS). Similar to previous studies, we find that the bulge exhibits a strong vertical metallicity gradient, and that at least two peaks in the metallicity distribution functions appear at b < -5{deg}. We can discern a metal-poor ([Fe/H] ~ -0.3) and metal-rich ([Fe/H] ~ +0.2) abundance distribution that each show clear systematic trends with latitude, and may be best understood by changes in the bulge's star formation/enrichment processes. Both groups exhibit asymmetric tails, and as a result we argue that the proximity of a star to either peak in [Fe/H] space is not necessarily an affirmation of group membership. The metal- poor peak shifts to lower [Fe/H] values at larger distances from the plane while the metal-rich tail truncates. Close to the plane, the metal-rich tail appears broader along the minor axis than in off-axis fields. We also posit that the bulge has two metal-poor populations - one that belongs to the metal-poor tail of the low latitude and predominantly metal-rich group, and another belonging to the metal-poor group that dominates in the outer bulge. We detect the X-shape structure in fields with |Z| > 0.7 kpc and for stars with [Fe/H] > -0.5. Stars with [Fe/H] < -0.5 may form a spheroidal or 'thick bar' distribution while those with [Fe/H] ~> -0.1 are strongly concentrated near the plane.2022MNRAS.515.1469Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/515/1469CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/148/67 : Abundances of 156 bulge red giants (Johnson+, 2014)J/ApJ/721/L28 : Red clump stars in Galactic Bulge from OGLE-IIIJ/ApJ/900/4 : Abundances and ages of stars in the Milky Way bulgeJ/ApJ/732/108 : Abundances of 92 giants in Plaut's window (Johnson+, 2011)J/A+A/605/A89 : Abundances of microlensed Bulge dwarf stars. VI.J/A+A/549/A147 : Abundances of microlensed bulge dwarf stars. V.J/A+A/530/A54 : Abundances of 650 bulge red giants (Gonzalez+, 2011)J/A+A/513/A35 : Abundances of Galactic red giants (Alves-Brito+, 2010)J/A+A/559/A98 : JK photometry in BUL_SC9 and BUL_SC29 (Valenti+, 2013)J/A+A/562/A66 : GIRAFFE Inner Bulge Survey (GIBS). I. (Zoccali+, 2014)J/A+A/599/A12 : [Fe/H] and kinematics of 26 Galactic bulge fieldsJ/A+A/653/A143 : A2A catalog of 21000 bulge stars from ARGOS surveyJ/MNRAS/428/3660 : ARGOS line list {lambda}8395-8830{AA} (Freeman+, 2013)J/MNRAS/486/5349 : Chemical compositions of Galactic bulge stars (Duong+, 2019)III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)II/337 : VISTA Variables in the Via Lactea Survey DR1 (Saito+, 2012)I/350 : Gaia EDR3 (Gaia Collaboration, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/515/1469https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/515/1469http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/515/1469https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/515/1469https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/515/1469http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/515/1469GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/515/1469/table1 (Final red clump stars bulge members catalogue)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/515/1469/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/515/1469/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/515/1469/table1?GETtext/xml+votable180.050000true263.73815-39.341790.0055555555555555564/1792-1793 1795-1796 1798-1799 5/7176-7177 7190 7221 7240-7242 7264 10583 10589 11946 6/28712-28713 28716-28717 28754-28755 28764 28766-28767 28865 28868-28869 28880-28881 28883 28972-28974 29060 29062 29064-29065 42325 42327 42331 42353 42355 42361 42364-42365 47790-47791 47802-47803 47806-478072.3230668610021367e-19 6.11321178556617e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/515/1469?format=asciiOpticaldefaultJ/MNRAS/515/1469/table1Final red clump stars bulge members cataloguerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000) (RA)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000) (DEC)degpos.eq.dec;meta.mainindexedumagApparent magnitude in CTIO/DECam u filter with {lambda}_mean_ = 3821{AA} (u)magphot.mag;em.opt.Ufloate_umagMean uncertainty of umag (u_err_)magstat.error;phot.magfloatgmagApparent magnitude in CTIO/DECam g filter with {lambda}_mean_ = 4862{AA} (g)magphot.mag;em.opt.Bfloate_gmagMean uncertainty of gmag (g_err_)magstat.error;phot.magfloatimagApparent magnitude in CTIO/DECam i filter with {lambda}_mean_ = 7850 {AA} (i)magphot.mag;em.opt.Ifloate_imagMean uncertainty of imag (i_err_)magstat.error;phot.magfloatAuExtinction coefficient in CTIO/DECam u filter (A_u_)magphys.absorption;em.opt.UfloatAgExtinction coefficient in CTIO/DECam g filter (A_g_)magphys.absorption;em.opt.BfloatAiExtinction coefficient in CTIO/DECam i filter (A_i_)magphys.absorption;em.opt.IfloatDStar distance computed with the equation 7 of the section 2 BDBS data selection (Dist.)kpcpos.distance;arithfloate_DMean {sigma} propagated error of D computed with equation 10 of the section 3.1 ({sigma}_Dist_)kpcstat.error;arithfloat[Fe/H]Iron to hydrogen abundance ratio computed with colour-metallicity equation 8 of the section 3.1 ([Fe/H])log(Sun)phys.abund.Fe;arith.ratiofloate_[Fe/H]Mean {sigma} propagated error of [Fe/H] computed with equation 9 of the section 3.1 ({sigma}_[Fe/H]_)log(Sun)stat.error;phys.abund.FefloatGaiaEDR3Display the GaiaEDR3 data Cat. I/350meta.ref.urlchar