J/A+A/589/A83ivo://CDS.VizieR/J/A+A/589/A83doi:10.26093/cds/vizier.35890083CDSGebran M.Farah W.Paletou F.Monier R.Watson V.2017-10-13T15:41:36Z2016-04-18T07:26:58ZCDS support team

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

cds-question@unistra.fram-starsmetallicityeffective-temperatureWe present an automated procedure that simultaneously derives the effective temperature Teff, surface gravity logg, metallicity [Fe/H], and equatorial projected rotational velocity vsini for "normal" A and Am stars. The procedure is based on the principal component analysis (PCA) inversion method, which we published in a recent paper. A sample of 322 high-resolution spectra of F0-B9 stars, retrieved from the Polarbase, SOPHIE, and ELODIE databases, were used to test this technique with real data. We selected the spectral region from 4400-5000 Ang as it contains many metallic lines and the Balmer H{beta} line. Using three data sets at resolving powers of R=42000, 65000 and 76000, about ~6.6x10^6 synthetic spectra were calculated to build a large learning database. The Online Power Iteration algorithm was applied to these learning data sets to estimate the principal components (PC). The projection of spectra onto the few PCs offered an efficient comparison metric in a low-dimensional space. The spectra of the well-known A0- and A1-type stars, Vega and Sirius A, were used as control spectra in the three databases. Spectra of other well-known A-type stars were also employed to characterize the accuracy of the inversion technique. We inverted all of the observational spectra and derived the atmospheric parameters. After removal of a few outliers, the PCA-inversion method appeared to be very efficient in determining Teff, [Fe/H], and vsini for A/Am stars. The derived parameters agree very well with previous determinations. Using a statistical approach, deviations of around 150K, 0.35dex, 0.15dex, and 2km/s were found for Teff, logg, [Fe/H], and vsini with respect to literature values for A-type stars. The PCA inversion proves to be a very fast, practical, and reliable tool for estimating stellar parameters of FGK and A stars and for deriving effective temperatures of M stars.2016A&A...589A..83Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/589/A83CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIII/260 : General Catalogue of Ap and Am stars (Renson+ 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/589/A83https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/589/A83http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/589/A83https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/589/A83https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/589/A83http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/589/A83GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/589/A83/table2 (Inverted effective temperatures, surface gravities, projected equatorial rotational velocities, metallicities, and radial velocities for the selected A stars of PolarBase, SOPHIE, and ELODIE databases)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/589/A83/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/589/A83/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/589/A83/table2?GETtext/xml+votable180.050000true251.94341335.24674440.0055555555555555566/116 161 331 433 456 461 463 472 474 478 485 496 689 765 812 871 1033 1035 1145 1283 1313 1337 1505 1714 1759 1888 1955 2225 2237 2289 2296 2317 2335 2340 2360 2395 2591 2697 2771 2789 2924 3164 3475 3625 3710 4140 4181 4224 4687 4696-4698 4702 4709 4720 4724 4890 5065 5149 5267 5373 5451 5717 5872 6008 6073 6082 6340 6539 6940 7138 7205 7267 7332 7486-7487 7865 8389 8518 8571 8597 8687 8803 8899 8969 9133 9310 9380 9502 9507 9716 9759 9836 9849 10000 10276 10317 10614 10660 10741 10796 11031 11109 11193 11204 11231 11290 11356 11678 12491 12732 12881 13127 13411 14059 14197 14218 14224 14641 14770 14852 14906 15179 15523 15583 15739 15836 15859 15958 15975 16334 17194 17573 17888 18493 18804 19022 19271 19309 19329 19376 19384 19464 19825 19989 20012 20125 20184 20322 20338 20940 21060 21397 21436 21833 22069 22112 22114 22120 22167 22250 22300 22370 22822-22823 22892 23190 23323 23375-23376 23383 23392 23408 23416 23426 23493 23502 23514 23518 23526 23537-23539 23546-23547 23658 23717 23864 23870 24004 24207 24223 24315 25789 25809 25973 26014 26381 27081-27082 27102 27105 27115 27462 27468 27473 27622 27756 27779 27789 27798 27816 27818-27819 27826 27885 27887 27890 27909 27919 27985 27993 28035 28039 28094 28131 28137 28142 28191 28208 28316 28396 28433 28439 28480-28482 28484 28489-28490 28494 28516 30106 30269 30274 30434 30438-30439 30539 31511 31650 31744 31812 31930 32202 32267 32297 32310 32475 32613 39230 40659 42464 48591 48900https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/589/A83?format=asciiOpticaldefaultJ/A+A/589/A83/table2Inverted effective temperatures, surface gravities, projected equatorial rotational velocities, metallicities, and radial velocities for the selected A stars of PolarBase, SOPHIE, and ELODIE databases[Fe/H]c? Closest Iron abundancephys.abund.FefloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar name or numbermeta.id;meta.maincharOutliers[1] Data outlier (1)meta.codecharTeffEffective temperatureKphys.temperature.effectivefloatTeffc? Closest effective temperatureKphys.temperature.effectivefloatnullableTeffm? Median effective temperatureKphys.temperature.effective;stat.medianfloatnullableloggLogarithm of gravitylog(cm.s**-2)phys.gravityfloatloggc? Closest logarithm of gravitylog(cm.s**-2)phys.gravityfloatnullableloggm? Median logarithm of gravitylog(cm.s**-2)phys.gravity;stat.medianfloatnullablevsiniProjected Rotational Velocitykm/sphys.veloc.rotatfloatvsinic? Closest projected rotational velocitykm/sphys.veloc.rotatfloatnullablevsinim? Median projected rotational velocitykm/sphys.veloc.rotat;stat.medianfloatnullable[Fe/H]Iron abundance relative to the sunphys.abund.Fefloat[Fe/H]m? Median Iron abundancephys.abund.Fe;stat.medianfloatnullableRVRadial Velocitykm/sphys.veloc;pos.heliocentricfloatComComments on stars (2)meta.notecharSimbadSimbad column added by the CDSmeta.ref.urlchar_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