J/AJ/110/1186ivo://CDS.VizieR/J/AJ/110/1186doi:10.26093/cds/vizier.51101186CDSNemec J.M.Mateo M.Burke M.Olszewski E.W.2023-04-06T16:50:17Z1998-09-07T14:30:21ZCDS support team

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

cds-question@unistra.frglobular-star-clustersvariable-starsccd-photometryThe results of a major search for photometrically variable blue straggler stars (BSs) in the extremely metal-poor globular cluster NGC 5053 are presented. The survey is based on photometry of over 200 CCD frames (BVI passbands) taken on 18 nights between 1985 and 1994. Five of the 16 BSs monitored for variability are identified as SX Phe stars and their photometric characteristics derived. These five stars are among the shortest-period (49<P<57min), lowest luminosity (3.0<~M_V<~3.3mag), smallest amplitude (0.08<~A_V<~0.25mag) SX Phe stars presently known. Their colors and locations in both B and V period-luminosity (P-L) diagrams suggest that four of the stars (blue stragglers 11, 13, 14, and 15 in the Nemec & Cohen 1989 catalog (1989ApJ...336..780N) are fundamental-mode pulsators, while the fifth and bluest star, No. 7, appears to be a first-overtone pulsator. One of the stars, No. 11, exhibits cycle-to-cycle light variations that are consistent with multimode pulsations; however, not enough photometric information is available to derive its secondary pulsation period. Masses for the stars, estimated directly from the general equation of stellar pulsation and relative to the RR Lyrae stars, range from 0.53M_{sun}_ (NC7) to 1.8M_{sun}_ (NC13). The SX Phe stars are used to derive improved P-L-[Fe/H] relations for SX Phe stars, from which a revised distance modulus of (m-M)0=16.06 is obtained for NGC 5053.1995AJ....110.1186Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/110/1186CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/110/1186https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/110/1186http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/110/1186https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/110/1186https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/110/1186http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/110/1186GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/110/1186/table3Photometry of the SKJ standard starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar name from Sandage et al. (1977AJ.....82..389S)meta.id;meta.maincharTypeType of star (1)src.classcharBmagSKJSKJ B magnitude (2)magphot.mag;em.opt.BfloatBmagMean B magnitude derived by authorsmagphot.mag;em.opt.Bfloate_BmagStd dev in B for all nightsmagstat.errorfloato_BmagNumber of B frames star measured onmeta.numberintn_BmagNumber of nights B measurements mademeta.noteintVmagSKJSKJ V magnitudemagphot.mag;em.opt.VfloatVmagMean V magnitude derived by authorsmagphot.mag;em.opt.Vfloate_VmagStd dev in V for all nightsmagstat.errorfloato_VmagNumber of V frames star measured onmeta.numberintn_VmagNumber of nights V measurements mademeta.noteintB-V(SKJ)SKJ B-V colormagphot.color;em.opt.B;em.opt.VfloatB-VMean B-V colormagphot.color;em.opt.B;em.opt.VfloatJ/AJ/110/1186/table4Mean B,V photometry of the blue stragglersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar number from Nemec and Cohen catalog (1989ApJ...336..780N)meta.id;meta.mainintf_Star[v] Indicates photometric variabilitymeta.code.errorcharVmagDerived mean V magnitudemagphot.mag;em.opt.Vfloate_VmagStd dev in V magnitudemagstat.errorfloato_VmagNumber of V frames star measured onmeta.numberintn_VmagNumber of nights V measurements mademeta.noteintBmagDerived mean B magnitudemagphot.mag;em.opt.Bfloate_BmagStd dev in Bmagmagstat.errorfloato_BmagNumber of B frames star measured onmeta.numberintn_BmagNumber of nights B measurements mademeta.noteintB-VB-V colormagphot.color;em.opt.B;em.opt.Vfloate_B-VB-V errormagstat.errorfloatJ/AJ/110/1186/table5Summary of the blue straggler monitoringStarStar numbermeta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintVmagDerived mean V magnitudemagphot.mag;em.opt.VfloatB-VB-V colormagphot.color;em.opt.B;em.opt.Vfloatu_B-VB-V uncertainty flagmeta.code.errorcharBehavePhotometric behavior, e.g. "constant"meta.codecharConfidConfidence rating, e.g. "high"meta.codecharJ/AJ/110/1186/table6Photometry of blue straggler 10 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table7Photometry of blue straggler 12 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table8Photometry of blue straggler 19 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table9Photometry of blue straggler 21 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table10Photometry of blue straggler 23 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table11Photometry of blue straggler 25 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table12*Photometry of blue straggler 7 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table13Photometry of blue straggler 11 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table14Photometry of blue straggler 13 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table15Photometry of blue straggler 14 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table16Photometry of blue straggler 15 in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight numbermeta.id;meta.mainintHJD-2440000HJD (epoch 2440000) of observationdtime.epochdoubleVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? V magnitude errormagstat.errorfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? B errormagstat.errorfloatnullableJ/AJ/110/1186/table17*Properties of the five SX Phe stars in NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPropertyProperty of SX Phe starmeta.notecharNC7Value of property for NC7stat.valuecharNC11Value of property for NC11stat.valuecharNC13Value of property for NC13stat.valuecharNC14Value of property for NC14stat.valuecharNC15Value of property for NC15stat.valuecharJ/AJ/110/1186/table18Derived log (P)-m0 (M15) relationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBand[BVK] Passband (1)meta.notecharTypeType of variable starmeta.code;src.varcharMode[FH] Pulsation mode (2)meta.notecharNumNumber of starsmeta.numberintIntInterceptstat.fit;arith.zpfloatSlope[]? Slopestat.fit.paramfloatnullablee_Slope[]? Slope standard errorstat.errorfloatnullable