J/AJ/145/43ivo://CDS.VizieR/J/AJ/145/43doi:10.26093/cds/vizier.51450043CDSKaluzny J.Thompson I.B.Rozyczka M.Dotter A.Krzeminski W.Pych W.,Rucinski S.M.Burley G.S.Shectman S.A.2017-07-11T13:08:53Z2014-03-24T09:26:57ZCDS support team

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

cds-question@unistra.frglobular-star-clusterseclipsing-binary-starsradial-velocityWe use photometric and spectroscopic observations of the eclipsing binaries V65, V66, and V69 in the field of the globular cluster M4 to derive masses, radii, and luminosities of their components. The orbital periods of these systems are 2.29, 8.11, and 48.19days, respectively. The measured masses of the primary and secondary components (M_p_ and M_s_) are 0.8035+/-0.0086 and 0.6050+/-0.0044M_{sun}_ for V65, 0.7842+/-0.0045 and 0.7443+/-0.0042M_{sun}_ for V66, and 0.7665+/-0.0053 and 0.7278+/-0/0048M_{sun}_ for V69. The measured radii (R_p_ and R_s_) are 1.147+/-0.010 and 0.6110 +/- 0.0092R_{sun}_ for V66, 0.9347+/-0.0048 and 0.8298+/-0.0053R_{sun}_ for V66, and 0.8655+/-0.0097 and 0.8074+/-0.0080R_{sun}_ for V69. The orbits of V65 and V66 are circular, whereas that of V69 has an eccentricity of 0.38. Based on systemic velocities and relative proper motions, we show that all three systems are members of the cluster. We find that the distance to M4 is 1.82+/-0.04kpc-in good agreement with recent estimates based on entirely different methods. We compare the absolute parameters of V66 and V69 with two sets of theoretical isochrones in mass-radius and mass-luminosity diagrams, and for assumed [Fe/H]=-1.20, [{alpha}/Fe]=0.4, and Y=0.25 we find the most probable age of M4 to be between 11.2 and 11.3Gyr. Color-magnitude diagram (CMD) fitting with the same parameters yields an age close to, or slightly in excess of, 12Gyr. However, considering the sources of uncertainty involved in CMD fitting, these two methods of age determination are not discrepant. Age and distance determinations can be further improved when infrared eclipse photometry is obtained.2013AJ....145...43Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/145/43CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)J/AJ/136/400 : Cl* NGC 6397 SAW V32 V light curve (Kaluzny+, 2008)J/ApJ/443/124 : Radial Velocities of Stars in M4 (Peterson+ 1995)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/145/43https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/145/43http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/145/43https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/145/43https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/145/43http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/145/43GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/145/43/minimaCombined table from original tablesEEclipse (1)meta.number;time.periodfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarSimbad column added by the CDSmeta.id;meta.maincharf_E[a] The orbit is eccentric, and the secondary minimum occurs at phase 0.6086052(+/-0.0000077)meta.codecharHJDHeliocentric Julian Date (HJD-2400000)dtime.epochdoublee_HJD1{sigma} uncertainty in HJDdstat.error;time.epochdoubleO-CThe (O-C) residualdstat.fit.residual;stat.fit.omcdoubleJ/AJ/145/43/velocCombined table from original tablesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarSimbad column added by the CDSmeta.id;meta.maincharHJDHeliocentric Julian Date at mid-exposure (HJD-2450000)dtime.epochdoubleRV1Radial velocity of the primary componentkm/sspect.dopplerVelocfloatRV2Radial velocity of the secondary componentkm/sspect.dopplerVelocfloatRV3? Radial velocity of the contaminating star (1)km/sspect.dopplerVelocfloatnullablePhaseOrbital phase (2)time.phasefloat