J/ApJ/836/77ivo://CDS.VizieR/J/ApJ/836/77doi:10.26093/cds/vizier.18360077CDSYee S.W.Petigura E.A.von Braun K.2017-11-13T13:05:24Z2017-10-16T09:03:22ZCDS support team

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

cds-question@unistra.frspectroscopymetallicityeffective-temperaturestellar-massesstellar-agesvisible-astronomytrigonometric-parallaxClassification of stars, by comparing their optical spectra to a few dozen spectral standards, has been a workhorse of observational astronomy for more than a century. Here, we extend this technique by compiling a library of optical spectra of 404 touchstone stars observed with Keck/HIRES by the California Planet Search. The spectra have high resolution (R~60000), high signal-to-noise ratio (S/N~150/pixel), and are registered onto a common wavelength scale. The library stars have properties derived from interferometry, asteroseismology, LTE spectral synthesis, and spectrophotometry. To address a lack of well-characterized late-K dwarfs in the literature, we measure stellar radii and temperatures for 23 nearby K dwarfs, using modeling of the spectral energy distribution and Gaia parallaxes. This library represents a uniform data set spanning the spectral types ~M5-F1 (T_eff_~3000-7000K, R_*_~0.1-16R_{Sun}_). We also present "Empirical SpecMatch" (SpecMatch-Emp), a tool for parameterizing unknown spectra by comparing them against our spectral library. For FGKM stars, SpecMatch-Emp achieves accuracies of 100K in effective temperature (T_eff_), 15% in stellar radius (R_*_), and 0.09dex in metallicity ([Fe/H]). Because the code relies on empirical spectra it performs particularly well for stars ~K4 and later, which are challenging to model with existing spectral synthesizers, reaching accuracies of 70K in T_eff_, 10% in R_*_, and 0.12dex in [Fe/H]. We also validate the performance of SpecMatch-Emp, finding it to be robust at lower spectral resolution and S/N, enabling the characterization of faint late-type stars. Both the library and stellar characterization code are publicly available.2017ApJ...836...77Yhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/836/77CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)I/337 : Gaia DR1 (Gaia Collaboration, 2016)J/PASP/110/863 : Stellar Spectral Flux Library: 1150-25000{AA} (Pickles 1998)J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)J/ApJ/680/728 : Diameters of exoplanet host stars (Baines+, 2008)J/ApJ/694/1085 : Radii of exoplanet host stars (van Belle+, 2009)J/other/A+ARV/18.67 : Accurate masses and radii of normal stars (Torres+, 2010)J/MNRAS/423/122 : Abundances of 93 solar-type Kepler targets (Bruntt+, 2012)J/ApJ/771/40 : Main-sequence A, F, G & K stars photometry (Boyajian+, 2013)J/ApJ/768/155 : RVs and photometry of HD 38529 system (Henry+, 2013)J/ApJ/767/127 : Asteroseismic solutions for 77 Kepler stars (Huber+, 2013)J/AJ/145/52 : Abundances of late K & M dwarfs in bin. systems (Mann+, 2013)J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)J/ApJS/225/32 : Extended abundance analysis of cool stars (Brewer+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/836/77https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/836/77http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/836/77https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/836/77https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/836/77http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/836/77GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/836/77/table1 (Properties of 23 K-dwarfs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/836/77/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/836/77/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/836/77/table1?GETtext/xml+votable180.050000true4.7731761-9.96485250.005555555555555556Cone search capability for table J/ApJ/836/77/table6 (Empirical SpecMatch library)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/836/77/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/836/77/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/836/77/table6?GETtext/xml+votable180.050000true173.6228631-32.83134190.0055555555555555566/131 137 174 257 414 546 649 679 684 753 811 824 871 1033 1201 1237 1341 1415 1530 1672 1827 1875 1938 2497 2512 2515 2737 2822 3102 3118 3372 3639 3714 3876 3979 4286 4366 4429 4555 4620 4632 4854 5009 5304 5309 5420 5434 5488 5534 5553 5556 5670 5676 5836 5853 6006 6142 6287 6339 6489 6584 6672 6737 7240 7264 7299 7352 7373 7736 7746 8224 8357 8614 8618 8723 8788 8790 8843 8993 8995 9365 9403 9435 9476 9585 9656 9801 9843 10004 10031 10149 10464 10548 10649 10740 10766 10854 10983 11142 11165 11314 11403 11461 11633 11636 12146 12296 12306 12340 12347 12352 12388 12418 12592 12612 12662 12922 12944 12983 13134 13301 13487 13650 13946 14180 14277 14278 14416 14419 14578 14581 14624 14709 14751 14754 14757 14763 14765 14767 14770 14776 14777 14779 14794 14819 14824 14827 14850 14901 14918 14921 14930 14931 14932 14933 14935 14941 14948 14952 14959 14960 14966 14967 14969 15041 15044 15061 15062 15106 15107 15110 15112 15118 15121 15124 15131 15132 15145 15146 15156 15170 15174 15178 15311 15356 15376 15602 16069 16350 16462 16590 16639 16678 16679 16758 16790 16892 16941 16971 17218 17253 17266 17314 17419 17425 17496 17572 17607 17752 17777 17870 18139 18171 18172 18195 18343 18496 18512 18551 18553 18666 18764 18809 18821 18947 19064 19139 19466 19541 19585 19669 19796 19904 19912 20023 20071 20100 20145 20328 20633 20665 20701 20732 21151 21171 21484 21550 21726 21747 21838 21906 21936 21953 22040 22120 22157 22309 22490 22571 22626 22708 22807 22981 23013 23190 23201 23367 23369 23414 23441 23544 23661 23665 23681 23731 23820 23867 23871 24117 24151 24178 24227 24568 24702 24713 24924 24991 25342 25538 25571 25595 25692 26160 26216 26266 26335 26379 26394 26551 26560 26575 26583 26727 26761 26772 26779 26972 26997 27109 27164 27201 27314 27335 27392 27912 28009 28044 28076 28085 28494 28548 28605 28668 28987 29084 29291 29413 29541 29680 29684 29852 30278 30289 30505 30529 30572 30604 30665 30771 30965 31068 31087 31416 31606 31751 31781 32115 32192 32318 32335 32345 32485 32491 32561 32645 34673 35753 35816 36049 36069 36070 36092 36115 36162 36174 36347 36412 36562 36693 36697 36723 36746 40101 40590 40610 40830 43677 44284 44774 44891 44921 44937 44959 45012 46566 46959 48549 48658 48926 49060https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/836/77?format=asciiOpticaldefaultJ/ApJ/836/77/table1Properties of 23 K-dwarfse_Teff[177/301] Uncertainty in TeffKstat.error;phys.temperature.effectiveintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject identifiermeta.id;meta.maincharHIPHipparcos identifiermeta.idintVmag[7.9/10.1] V band magnitudemagphot.mag;em.opt.Vfloate_Vmag[0.02/0.05] Uncertainty in Vmagmagstat.error;phot.mag;em.opt.VfloatKmag[5.2/6.9] K band magnitudemagphot.mag;em.IR.Kfloate_Kmag[0.03/0.06] Uncertainty in Kmagmagstat.error;phot.mag;em.IR.KfloatTeff[3904/4615] Effective temperatureKphys.temperature.effectiveintFbol[0.5/2.8] Bolometric flux; 1e-8erg/cm^2^/s1e-11W.m**-2phot.flux.bolfloate_Fbol[0.01/0.02] Uncertainty in Fbol1e-11W.m**-2stat.errorfloatplx[38.5/68.5] Parallaxmaspos.parallax.trigfloate_plx[0.2/1.6] Uncertainty in plxmasstat.error;pos.parallaxfloatR*[0.5/0.8] Stellar radiussolRadphys.size.radiusfloate_R*[0.04/0.1] Uncertainty in R*solRadstat.errorfloat[Fe/H][-0.9/0.2] Metallicitylog(Sun)phys.abund.Zfloate_[Fe/H][0.1] Uncertainty in [Fe/H]log(Sun)stat.error;phys.abund.Fefloatr_plx[1/2] Reference code for plx (1)meta.ref;pos.frameint2MDisplay the 2MASS data (Cutri+ 2003, II/246) within 3"meta.ref.urlcharSimbadSimbad 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.mainJ/ApJ/836/77/table6Empirical SpecMatch libraryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject identifiermeta.id;meta.maincharTeff[3056/6738] Effective temperatureKphys.temperature.effectiveinte_Teff[9/301] Uncertainty in TeffKstat.error;phys.temperature.effectiveintR*[0.1/15.8] Stellar radiussolRadphys.size.radiusfloate_R*[0.001/1.2] Uncertainty in R*solRadstat.errorfloatlog(g)[2.1/5.2] Log stellar surface gravitylog(cm.s**-2)phys.gravityfloate_log(g)[0.01/0.2] Uncertainty in log(g)log(cm.s**-2)stat.errorfloat[Fe/H][-0.6/0.6] Metallicitylog(Sun)phys.abund.Zfloate_[Fe/H][0.03/0.1] Uncertainty in [Fe/H]log(Sun)stat.error;phys.abund.FefloatM*[0.1/1.7] Stellar masssolMassphys.massfloate_M*[0/0.3] Uncertainty in M*solMassstat.errorfloatlogAge[9/10.2] Log stellar agelog(yr)time.agefloate_logAge[0.03/0.6] Uncertainty in logAgelog(yr)stat.error;time.agefloatplx[1.8/549]? Parallaxmaspos.parallax.trigfloatnullableVmag[3.2/12.3]? V band magnitudemagphot.mag;em.opt.VfloatnullableNotesAdditional note code(s) (1)meta.notecharSCatDisplay data from Mann+, 2015, J/ApJ/804/64; Brewer+, 2016, J/ApJS/225/32 and Bruntt+, 2012, J/MNRAS/423/122, within 3"meta.ref.urlintnullableGaiaDisplay data from Gaia DR1 (I/337) within 3"meta.ref.urlchar2MDisplay the 2MASS data (Cutri+ 2003, II/246) within 3"meta.ref.urlcharSimbadSimbad 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