J/MNRAS/517/1907ivo://CDS.VizieR/J/MNRAS/517/1907doi:10.26093/cds/vizier/bg-g5-1vkCDSJurcsik J.Juhasz A.2026-08-03T07:31:58Z2025-11-18T15:18:54ZCDS support team

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

cds-question@unistra.frvariable-starsgalactic-centermilky-way-galaxyphotometryvisible-astronomyinfrared-astronomymetallicitystellar-radiiabsolute-magnitudeeffective-temperatureIn this paper, we report on the detection of RRab stars with quasi-identical-shape light curves but period differences as large as 0.05-0.21 d using the Galactic bulge data of the OGLE-IV survey. We have examined stars with shorter periods than the Oosterhoff I ridge of the bulge. These stars generally have smaller amplitudes and larger Fourier phase-differences than the typical bulge RRab stars have at the same period. Many of these 'anomalous' stars have good-quality light curves without any sign of the Blazhko modulation. Examining their Fourier parameters revealed that several of these stars show very similar light curve to the typical bulge RR Lyrae. We found hundreds of quasi-identical-shape light-curve pairs with different periods between the 'anomalous'- and the 'normal'-position RRab stars based on the OGLE I-band data. The OGLE V-band, and the archive VVV and MACHO surveys Ks-, b- and r-band data of these stars were also checked for light-curve-shape similarity. Finally, 149 pairs with identical-shape light curves in each available photometric band were identified. Calculating the physical properties of the variables using empirical formulae, on average, -0.5 dex, -0.13 mag, 0.67, and 165 K differences between the [Fe/H], M_V_, R/R_{Sun}_, and T_eff_ values of the members of the pairs are derived, being the short-period stars less metal-poor, fainter, smaller, and hotter than the long-period variables. To explain the existence of variables with different physical properties and pulsation periods but with identical-shape light curves is a challenging task for modelling.2022MNRAS.517.1907Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/517/1907CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/491/4752 : Modelled parameters of Cepheid and RR LyraeJ/MNRAS/484/4833 : Oosterhoff dichotomy in Galactic bulge (Prudil+, 2019)J/MNRAS/466/2602 : Blazhko effect in Galactic RR Lyrae (Prudil+, 2017)J/MNRAS/402/226 : NGC 5053 variables VrI light curves (Arellano Ferro+, 2010)J/ApJ/920/33 : Fe/H estimation of 104 RR Lyrae from I- light curveJ/ApJ/914/10 : Field RR Lyrae as Gal. probes. III. AbundancesJ/ApJ/857/54 : JHKs photometry of VVV RR Lyrae stars (Dekany+, 2018)J/A+A/371/579 : Empirical relations for cluster RR Lyrae (Kovacs+, 2001)J/AcA/64/177 : VI light curves of Galactic Bulge RR LyraeII/376 : VISTA Variable in the Via Lactea Survey (VVV) DR4.2II/364 : VIRAC. The VVV Infrared Astrometric Catalogue (Smith+, 2019)II/337 : VISTA Variables in the Via Lactea Survey DR1 (Saito+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/517/1907https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/517/1907http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/517/1907https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/517/1907https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/517/1907http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/517/1907GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/517/1907/table1 (*Photometry band used and periods RRab pair stars quasi identical-shape lc at different periods)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/517/1907/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/517/1907/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/517/1907/table1?GETtext/xml+votable180.050000true258.5987553-29.33818110.005555555555555556Cone search capability for table J/MNRAS/517/1907/table2 (Derived physical parameters of RRab pair stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/517/1907/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/517/1907/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/517/1907/table2?GETtext/xml+votable180.050000true258.5987553-29.33818110.0055555555555555565/7183 7195 7216-7217 6/28709 28711 28713 28717-28719 28726-28730 28768 28776 28778-28779 28801 28817 28820-28821 28823 28842 28859 28882-28883 28907 29184 29249https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/517/1907?format=asciiOpticalInfrareddefaultJ/MNRAS/517/1907/table1*Photometry band used and periods RRab pair stars quasi identical-shape lc at different periodsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintOGLEsIdentification number of short-period pair member as in designation OGLE BLG-RRLYR-NNNNN (ID_s) (G1)meta.id.part;meta.mainintP17sDisplay for s members Blazhko effect in Galactic RR Lyrae from Prudil et al. 2017MNRAS.466.2602P, Cat. J/MNRAS/466/2602meta.ref.urlintnullableP19sDisplay for s members Oosterhoff dichotomy in Galactic bulge from Prudil et al. 2019MNRAS.484.4833P, Cat. J/MNRAS/484/4833meta.ref.urlintnullablePsPeriod of the short-period pair member (Period_s)dtime.perioddoubleOGLElIdentification number of long-period pair member as in designation OGLE BLG-RRLYR-NNNNN (ID_l) (G1)meta.id.part;meta.mainintP17lDisplay for l members Blazhko effect in Galactic RR Lyrae from Prudil et al. 2017MNRAS.466.2602P, Cat. J/MNRAS/466/2602meta.ref.urlintnullableP19lDisplay for l members Oosterhoff dichotomy in Galactic bulge from Prudil et al. 2019MNRAS.484.4833P, Cat. J/MNRAS/484/4833meta.ref.urlintnullablePlPeriod of the long-period pair member (Period_l)dtime.perioddoubleb-MACHO[+ -] Flag to indicate if the MACHO blue band light curve photometric data is used "+" or not "-" (b) (1)meta.code;em.opt.BcharSimbadSimbad column added by the CDSmeta.ref.urlcharV-OGLE[+] Flag to indicate if the OGLE-IV/OGLE-V V bands light curve photometric data is used "+" or not "-" (V) (1)meta.code;em.opt.Vcharr-MACHO[+ -] Flag to indicate if the MACHO red band light curve photometric data is used "+" or not "-" (r) (1)meta.code;em.opt.RcharI-OGLE[+ -] Flag to indicate if the OGLE-IV/OGLE-V I bands light curve photometric data is used "+" or not "-" (I) (1)meta.code;em.opt.IcharKs-VVV[+ -] Flag to indicate if the VVV IR K_s_ band light curve photometric data is used "+" or not "-" (Ks) (1)meta.code;em.IR.Kchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/MNRAS/517/1907/table2Derived physical parameters of RRab pair starsOGLElIdentification number of long-period pair member as in designation OGLE BLG-RRLYR-NNNNN (ID_l) (G1)meta.id.part;meta.mainintP17lDisplay for l members Blazhko effect in Galactic RR Lyrae from Prudil et al. 2017MNRAS.466.2602P, Cat. J/MNRAS/466/2602meta.ref.urlintnullableP19lDisplay for l members Oosterhoff dichotomy in Galactic bulge from Prudil et al. 2019MNRAS.484.4833P, Cat. J/MNRAS/484/4833meta.ref.urlintnullablePlPeriod of the long-period pair member (Period_l)dtime.perioddoubleSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintOGLEsIdentification number of short-period pair member as in designation OGLE BLG-RRLYR-NNNNN (ID_s) (G1)meta.id.part;meta.mainintP17sDisplay for s members Blazhko effect in Galactic RR Lyrae from Prudil et al. 2017MNRAS.466.2602P, Cat. J/MNRAS/466/2602meta.ref.urlintnullableP19sDisplay for s members Oosterhoff dichotomy in Galactic bulge from Prudil et al. 2019MNRAS.484.4833P, Cat. J/MNRAS/484/4833meta.ref.urlintnullablePsPeriod of the short-period pair member (Period_s)dtime.perioddouble[Fe/H]sIron to hydrogen abundance ratio for short-period pair member ([Fe/H]_s) (1)log(Sun)phys.abund.Fe;arith.ratio;meta.modelledfloat[Fe/H]s*Iron to hydrogen abundance ratio for short-period pair member ([Fe/H]_s*) (2)log(Sun)phys.abund.Fe;arith.ratio;meta.modelledfloat[Fe/H]lIron to hydrogen abundance ratio for long-period pair member ([Fe/H]_l) (1)log(Sun)phys.abund.Fe;arith.ratio;meta.modelledfloat[Fe/H]l*Iron to hydrogen abundance ratio for long-period ([Fe/H]_l*) (2)log(Sun)phys.abund.Fe;arith.ratio;meta.modelledfloatRsStar radius for short-period pair member (R_s) (1)solRadphys.size.radius;meta.modelledfloatRs*Star radius for short-period pair member (R_s*) (2)solRadphys.size.radius;meta.modelledfloatRlStar radius for long-period pair member (R_l) (1)solRadphys.size.radius;meta.modelledfloatRl*Star radius for long-period pair member (R_l*) (2)solRadphys.size.radius;meta.modelledfloatVsMagAbsolute V magnitude for short-period pair member (M_V_s) (1)magphys.magAbs;meta.modelledfloatVlMagAbsolute V magnitude for long-period pair member (M_V_l) (1)magphys.magAbs;meta.modelledfloatTeffsEffective temperature for short-period pair member (T_eff_s) (1)Kphys.temperature.effective;meta.modelledintTeffs*Effective temperature for short-period pair member (T_eff_s*) (2)Kphys.temperature.effective;meta.modelledintTefflEffective temperature for long-period pair member (T_eff_l) (1)Kphys.temperature.effective;meta.modelledintTeffl*Effective temperature for long-period pair member (T_eff_l*) (2)Kphys.temperature.effective;meta.modelledint_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main