THE LICK/SDSS LIBRARY. II. [Ca/Fe] AND [Mg/Fe] IN F, G, AND K STARS FROM SDSS-DR7

被引：10

作者：

Franchini, M. ^{[1
]}

Morossi, C. ^{[1
]}

Di Marcantonio, P. ^{[1
]}

Malagnini, M. L. ^{[1
,2
]}

Chavez, M. ^{[3
]}

机构：

[1] INAF Osservatorio Astron Trieste, I-34131 Trieste, Italy

[2] Univ Trieste, Dipartimento Fis, Sez Astron, I-34131 Trieste, Italy

[3] Inst Nacl Astrofis Opt & Electr, Puebla 72840, Mexico

来源：

ASTROPHYSICAL JOURNAL | 2011年 / 730卷 / 02期

基金：

美国国家科学基金会; 美国国家航空航天局;

关键词：

Galaxy: stellar content; stars: abundances; stars: fundamental parameters; stars: late-type; ALPHA-ENHANCED STARS; SYNTHETIC LICK INDEXES; DIGITAL SKY SURVEY; ABUNDANCE RATIOS; CHEMICAL EVOLUTION; SOLAR NEIGHBORHOOD; THICK DISK; MILKY-WAY; G-DWARF; SPECTRA;

D O I：

10.1088/0004-637X/730/2/117

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We analyzed the spectra of 17,600 F, G, and K stars extracted from the seventh Sloan Digital Sky Survey Data Release (SDSS-DR7) database in order to derive <[alpha/Fe]>, [Ca/Fe], and [Mg/Fe] ratios. Particular attention has been devoted to estimating homogeneous and self-consistent atmospheric parameter values, T-eff, log g, and [Fe/H], by comparing synthetic and observational Lick/SDSS indices. We present results for the sub-sample of more than 4000 spectra whose overall quality allowed us to derive fairly accurate stellar atmospheric parameter values and, therefore, reliable abundance ratios. A Monte Carlo approach was adopted to evaluate both the errors in the observational Lick/SDSS indices and in the derived parameter estimates. The analysis of the trends of [Ca/Fe] and [Mg/Fe] versus [Fe/H] pointed out that (1) the [Ca/Fe] and [Mg/Fe] ratios increase with decreasing [Fe/H] with different slopes reaching maximum average levels of +0.25 and +0.40 dex at [Fe/H] similar or equal to -1.75, respectively; (2) our sample contains, at a given [Fe/H], stars characterized by significantly different amounts of alpha-enhancement, thus belonging to different Galactic populations; and (3) the analyzed sample shows a predominance of thick disk stars for [Fe/H] > -0.5 and the presence of stars belonging to the "high-alpha" halo population for -2.0 < [Fe/H] < -0.5.

引用

页数：12

共 38 条

[1] THE SEVENTH DATA RELEASE OF THE SLOAN DIGITAL SKY SURVEY [J].

Abazajian, Kevork N. ;

Adelman-McCarthy, Jennifer K. ;

Agueros, Marcel A. ;

Allam, Sahar S. ;

Prieto, Carlos Allende ;

An, Deokkeun ;

Anderson, Kurt S. J. ;

Anderson, Scott F. ;

Annis, James ;

Bahcall, Neta A. ;

Bailer-Jones, C. A. L. ;

Barentine, J. C. ;

Bassett, Bruce A. ;

Becker, Andrew C. ;

Beers, Timothy C. ;

Bell, Eric F. ;

Belokurov, Vasily ;

Berlind, Andreas A. ;

Berman, Eileen F. ;

Bernardi, Mariangela ;

Bickerton, Steven J. ;

Bizyaev, Dmitry ;

Blakeslee, John P. ;

Blanton, Michael R. ;

Bochanski, John J. ;

Boroski, William N. ;

Brewington, Howard J. ;

Brinchmann, Jarle ;

Brinkmann, J. ;

Brunner, Robert J. ;

Budavari, Tamas ;

Carey, Larry N. ;

Carliles, Samuel ;

Carr, Michael A. ;

Castander, Francisco J. ;

Cinabro, David ;

Connolly, A. J. ;

Csabai, Istvan ;

Cunha, Carlos E. ;

Czarapata, Paul C. ;

Davenport, James R. A. ;

de Haas, Ernst ;

Dilday, Ben ;

Doi, Mamoru ;

Eisenstein, Daniel J. ;

Evans, Michael L. ;

Evans, N. W. ;

Fan, Xiaohui ;

Friedman, Scott D. ;

Frieman, Joshua A. .

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2009, 182 (02) :543-558

[2]

Allende PrietoC., 2006, ApJ, V636, P804

[3] Determination of effective temperatures for an extended sample of dwarfs and subdwarfs (F0-K5) [J].

Alonso, A ;

Arribas, S ;

MartinezRoger, C .

ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES, 1996, 117 (02) :227-254

[4] Tracing the galactic thick disk to solar metallicities [J].

Bensby, T. ;

Zenn, A. R. ;

Oey, M. S. ;

Feltzing, S. .

ASTROPHYSICAL JOURNAL, 2007, 663 (01) :L13-L16

[5]

BLACKWELL DE, 1990, ASTRON ASTROPHYS, V232, P396

[6] A compiled catalog of spectroscopically determined elemental abundances for stars with accurate parallaxes; Magnesium [J].

Borkova, TV ;

Marsakov, VA .

ASTRONOMY REPORTS, 2005, 49 (05) :405-416

[7] A comparison of the chemical evolutionary histories of the galactic thin disk and thick disk stellar populations [J].

Brewer, MM ;

Carney, BW .

ASTRONOMICAL JOURNAL, 2006, 131 (01) :431-454

[8]

CASAGRANDE L, 2010, ASTRON ASTROPHYS, V512, P54

[9] Medium-resolution Isaac Newton Telescope library of empirical spectra -: II.: The stellar atmospheric parameters [J].

Cenarro, A. J. ;

Peletier, R. F. ;

Sanchez-Blazquez, P. ;

Selam, S. O. ;

Toloba, E. ;

Cardiel, N. ;

Falcon-Barroso, J. ;

Gorgas, J. ;

Jimenez-Vicente, J. ;

Vazdekis, A. .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2007, 374 (02) :664-690

[10] Abundance gradients in the Milky Way for α elements, iron peak elements, barium, lanthanum, and europium [J].

Cescutti, G. ;

Matteucci, F. ;

Francois, P. ;

Chiappini, C. .

ASTRONOMY & ASTROPHYSICS, 2007, 462 (03) :943-U53

← 1 2 3 4 →