VI/54ivo://CDS.VizieR/VI/54CDSDorman B.2017-07-11T13:09:01Z2007-01-11T12:00:37ZCDS support team

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

cds-question@unistra.frmetallicitystellar-evolutionary-trackshorizontal-branch-starsThis data set consists of evolutionary sequences from the Zero Age Horizontal Branch (ZAHB) to the point where log L/Lsun reaches 2.25 on the lower AGB. These calculations have enhanced oxygen abundance according to a relation used by VandenBerg (1992ApJ...391..685V) and Bergbusch and VandenBerg (1992ApJS...81..163B) for main sequence and red-giant branch models. Also, zero age sequences for oxygen enhanced and scaled-solar compositions are given. Introduction: There are thirteen data files in this directory, ten of which contain evolutionary sequences from the ZAHB to the point where log(L/Lsun) reaches 2.25 on the lower AGB. These calculations have enhanced oxygen abundance according to a relation used by VandenBerg (1992) and Bergbusch and VandenBerg (1992) in computations of evolutionary tracks and isochrones for main sequence and red-giant branch models. The other three contain zero age sequences for oxygen enhanced and scaled-solar compositions, as explained below. The models with [O/Fe]>0 are described in more detail in Dorman (1992). Briefly, the models use Los Alamos (1977) high temperature opacities, Alexander (1980) low temperature opacities, the reaction rates listed in Caughlan and Fowler (1988), and the Eggleton et. al. (1973) equation of state. model atmospheres for surface pressures used by VandenBerg (1992), and a mixing length of 1.5 pressure scale heights. Accompanying scaled-solar evolution calculations may be available on request, through the address given below. A complete bibliography for the input physics in these models can be found from the 3 papers listed in the References below. Evolutionary sequences: The ten files are for ten different compositions, lying between [Fe/H]=-2.26 and -0.47. The filenames (f24a14.dat,f24b24.dat etc.) are significant in the sense that the `24' which appears in every name refers to the ZAMS helium abundance, to two significant figures. The `14', `24', `34' etc. gives the mantissa and exponent of the value of Z', the heavy element abundance of a model with the same [Fe/H], but without the oxygen enhancement. Thus, f24j63.dat contains sequences with the same iron abundance as scaled solar models with Z = 0.006. A summary of the contents of each file is given below. The tables here have been derived from the original calculations using cubic Hermite spline interpolation, and are tabulated at even intervals of the central helium abundances; the intervals change towards exhaustion. After Y is exhausted at the centre of the model, the tracks are tabulated at intervals of 0.25 Myr. ---------------------------------------------- Filename YHB [Fe/H] [O/Fe] Msh ---------------------------------------------- f24a14.dat 0.246 -2.26 0.75 0.4926 f24b24.dat 0.247 -2.03 0.70 0.4904 f24c34.dat 0.248 -1.78 0.66 0.4881 f24d44.dat 0.248 -1.66 0.63 0.4866 f24e64.dat 0.249 -1.48 0.60 0.4852 f24f13.dat 0.250 -1.26 0.55 0.4835 f24g23.dat 0.252 -1.03 0.50 0.4815 f24h33.dat 0.257 -0.78 0.39 0.4792 f24i43.dat 0.259 -0.65 0.30 0.4776 f24j63.dat 0.266 -0.47 0.23 0.4757 ---------------------------------------------- Zero Age Horizontal Branch models: There is one file for [O/Fe] > 0 models (zahbo.dat), and there are two for scaled solar calculations. The first of these (zahb.dat) contains ZAHB models for the [Fe/H] values which correspond to the enhanced oxygen sets. The other (zahbs.dat), containing models for just 3 compositions, has data for [Fe/H] = -0.23, 0 and +0.15 ( Z = 0.01, 0.0169 and 0.024). These have been calculated with the Krishna-Swamy scaled-solar T-tau relation and with mixing length 1.58 pressure scaleheights. They are not consistent with the others, therefore, and using them together to derive theoretical quantities as a function of metallicity may give spurious results. All of the oxygen-enhanced ZAHBs contain models for masses between about 0.5 and 1.5 solar masses, while the range of the scaled-solar models varies.1992ApJS...81..221Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/VI/54CatalogResearchIsServedByTAP VizieR generic servicerelated-toVI/65 : Evolutionary models of evolved stars (Dorman+ 1993https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=VI/54https://vizier.iucaa.in/viz-bin/VizieR-2?-source=VI/54http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=VI/54https://vizier.cds.unistra.fr/viz-bin/votable?-source=VI/54https://vizier.iucaa.in/viz-bin/votable?-source=VI/54http://vizieridia.saao.ac.za/viz-bin/votable?-source=VI/54GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultVI/54/zahbZero Age Horizontal Branch model. Scaled solar sequencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMSimbad column added by the CDSmeta.notecharYHB[0/1] Helium abundancephys.abund.Yfloat[Fe/H]Metallicity relative to Sun (log scale)log(Sun)phys.abund.Fefloat[O/Fe]Oxygen abundance relative to Sun (log scale)log(Sun)phys.abundfloatMshCore mass at He flashsolMassphys.massfloatMassStellar mass (solar units)solMassphys.massfloatlogLSurface luminosity (log scale)log(solLum)phys.luminosityfloatlogTeEffective temperature (log scale)log(K)phys.temperature.effectivefloatlog.gSurface gravity, cgs units (log scale)log(cm.s**-2)phys.gravityfloatMvAbsolute Visual magnitudemagphys.magAbs;em.opt.VfloatB-Vcolour indexmagphot.color;em.opt.B;em.opt.VfloatlogRRadius (log scale)log(cm)phys.size.radiusfloatlogTcCentral Temperature (log scale)log(K)phys.temperaturefloatlog.rho_cCentral density, cgs units (log scale)log(g.cm**-3)phys.densityfloatVI/54/evolCombined table from original tableslog.g? Surface gravity, cgs units (log scale)log(cm.s**-2)phys.gravityfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMassStellar masssolMassphys.massfloat[Fe/H]Metallicity relative to Sun (log scale)log(Sun)phys.abund.Fefloat[O/Fe]Oxygen abundance relative to Sun (log scale)log(Sun)phys.abundfloatAge? Age in Myr since ZAHBMyrtime.agefloatnullableYc[0/1]? Central helium fractionphys.abund.YfloatnullablelogL? Surface luminosity (log scale)log(solLum)phys.luminosityfloatnullablelogTe? Effective temperature (log scale)log(K)phys.temperature.effectivefloatnullableMvAbsolute Visual magnitude, derived from scale described by VandenBerg (1992ApJ...391..685V)magphys.magAbs;em.opt.VfloatB-Vcolour indexmagphot.color;em.opt.B;em.opt.VfloatlogTcCentral Temperature (log scale)log(K)phys.temperaturefloatlog.rho_cCentral density, cgs units (log scale)log(g.cm**-3)phys.densityfloatMccore? Mass of convective coresolMassphys.massfloatnullableMout? Mass at outer edge of semiconvection zonesolMassphys.massfloatnullableMshMass at peak energy production rate of Hydrogen burning shellsolMassphys.massfloatA? A = log.L/M^0.81, a quantity arising from pulsation models (1)stat.paramfloatnullablelogP? Period of RR Lyrae pulsation (log scale) in the fundamental mode (1)log(d)time.periodfloatnullable