J/MNRAS/456/1221ivo://CDS.VizieR/J/MNRAS/456/1221doi:10.26093/cds/vizier.74561221CDSRyabchikova T.Piskunov N.Pakhomov Y.Tsymbal V.Titarenko A.,Sitnova T.Alexeeva S.Fossati L.Mashonkina L.2024-08-15T20:17:10Z2016-11-16T09:02:37ZCDS support team

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

cds-question@unistra.frlate-type-starschemical-abundancesWe performed extensive tests of the accuracy of atmospheric parameter determination for FGK stars based on the spectrum fitting procedure Spectroscopy Made Easy (sme). Our stellar sample consists of 13 objects, including the Sun, in the temperature range 5000-6600K and metallicity range -1.4-/+0.4. The analysed stars have the advantage of having parameters derived by interferometry. For each star, we use spectra obtained with different spectrographs and different signal-to-noise ratios (S/N). For the fitting, we adopted three different sets of constraints and test how the derived parameters depend upon the spectral regions (masks) used in sme. We developed and implemented in sme a new method for estimating uncertainties in the resulting parameters based on fitting residuals, partial derivatives, and data uncertainties. For stars in the 5700-6600K range, the best agreement with the effective temperatures derived by interferometry is achieved when spectrum fitting includes the H{alpha} and H{beta} lines, while for cooler stars the choice of the mask does not affect the results. The derived atmospheric parameters do not strongly depend on spectral resolution and S/N of the observations, while the uncertainties in temperature and surface gravity increase with increasing effective temperature, with minima at 50K in Teff and 0.1dex in logg, for spectra with S/N=150-200. A non-local thermodynamic equilibrium (NLTE) analysis of the TiI/TiII and FeI/FeII ionization equilibria and abundances determined from the atomic CI (NLTE) and molecular CH species supports the parameters we derived with sme by fitting the observed spectra including the hydrogen lines.2016MNRAS.456.1221Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/456/1221CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/456/1221https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/456/1221http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/456/1221https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/456/1221https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/456/1221http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/456/1221GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/456/1221/table1 (List of investigated stars and spectrographs used to collect the spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/456/1221/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/456/1221/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/456/1221/table1?GETtext/xml+votable180.050000true114.82549785.22498750.0055555555555555566/2472 9459 12644 12983 17266 22120 22300 24924 26975 28664 36693 40692https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/456/1221?format=asciidefaultJ/MNRAS/456/1221/table1List of investigated stars and spectrographs used to collect the spectraSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharSpectSpectrographmeta.id;instrcharResResolution powerpos.angResolutionintProgProgram IDmeta.idcharn_Prog[a-e] Note on Prog (1)meta.notecharS/N? Average signal-to-noise ratio calculated in the three wavelength ranges discussed in Section 3.1stat.snrintnullableMaskMaskmeta.id;instrcharTeffS? SME effective temperatureKphys.temperature.effectiveintnullablee_TeffS? rms uncertainty on TeffSKstat.errorintnullableloggS? SME surface gravitylog(cm.s**-2)phys.gravityfloatnullablee_loggS? rms uncertainty on loggSlog(cm.s**-2)stat.errorfloatnullable[M/H]S? SME metallicityphys.abund.Fefloatnullablee_[M/H]S? rms uncertainty on [M/H]Sstat.error;phys.abundfloatnullableTeffI? Interferometry effective temperatureKphys.temperature.effectiveintnullablee_TeffI? rms uncertainty on TeffIKstat.errorintnullableloggI? Interferometry surface gravitylog(cm.s**-2)phys.gravityfloatnullablee_loggI? rms uncertainty on loggIlog(cm.s**-2)stat.errorfloatnullableRefI? Interferometry reference (2)meta.bibintnullableTeffO? Other spectroscopy effective temperatureKphys.temperature.effectiveintnullablee_TeffO? rms uncertainty on TeffOKstat.errorintnullableloggO? Other spectroscopy surface gravitylog(cm.s**-2)phys.gravityfloatnullablee_loggO? rms uncertainty on loggOlog(cm.s**-2)stat.errorfloatnullable[M/H]O? Other spectroscopy metallicityphys.abund.Fefloatnullablee_[M/H]O? rms uncertainty on [M/H]Ostat.error;phys.abundfloatnullableRefO? Other spectroscopy reference (2)meta.bibintnullable_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.mainnullable_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainnullableJ/MNRAS/456/1221/table2Atomic and molecular line parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambdaWavelength0.1nmem.wldoubleEl+IonSpeciesmeta.notecharlog(gf)Oscillator strengthphys.atmol.oscStrengthfloatExiExcitation energyeVphys.atmol.excitationfloatSourceSource code (1)meta.bibcharJ/MNRAS/456/1221/tablea1Laboratory wavelengths of the mask m6recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLambda1Lower value of wavelength interval0.1nmem.wl;stat.mindoubleLambda2Upper value of wavelength interval0.1nmem.wl;stat.maxdoubleNote[*] * indicates the beginning of each regionmeta.notechar